-,i(_ v....,.-......, a | b «

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FLOSCULARIA.

NATURAL HISTORY RAMBLES.

PONDS AND DITCHES.
BY

M. C. COOKE, M.A., LL.D.
AUTHOR OF " T H E WOODLANDS."

PUBLISHED UNDER THE DIRECTION

OF

THE COMMITTEE OF GENERAL LITERATURE AND EDUCATION
APPOINTED BY THE SOCIETY FOR PROMOTING
CHRISTIAN KNOWLEDGE.

LONDON:
SOCIETY FOR PROMOTING CHRISTIAN KNOWLEDGE,
NORTHUMBERLAND AVENUE, CHARING CROSS ;
4, ROYAL EXCHANGE;

AND 4 8 , PICCADILLY.

NEW YORK : POTT, YOUNG, & CO.

CONTENTS.
CHAPTER I.
STILL WATERS

...

page

7

CHAPTER II.
FLOWERING PLANTS

15

CHAPTER III.
PLANTS WITHOUT FLOWERS

36

CHAPTER IV.
FRESH-WATER ALG.E

49

CHAPTER V.
DESMIDS

69

CHAPTER VI.
DIATOMS

8$

CHAPTER VII.
LOW-LIFE (PROTOZOA)

99

6

PONDS AND DITCHES.

CHAPTER VIII.
HYDRAS

122

CHAPTER IX.
FRESH-WATER POLYZOA

...

132

CHAPTER X.
ROTIFERS

148

CHAPTER XL
LEECHES AND WORMS

174

CHAPTER XII.
SPIDERS, MITES, AND WATER-BEARS

185

CHAPTER XIII.
WATER-FLEAS

193

CHAPTER XIV.
AQUATIC LARVAE

207

CHAPTER XV.
ON COLLECTING AND EXAMINING

234

PONDS AND DITCHES,
C H A P T E R I.
STILL

WATERS.

I N in the present series of volumes, " Lakes and
Rivers" have already been provided for, which may be
interpreted as including all fresh-waters having a current, but exclusive of standing pools and stagnant
ditches. This at first sight might appear to be a
distinction without a difference, but we hope to make
it appear that there is a very considerable difference
between the two. The volume just alluded to includes the valleys through which the streams pursue
their course, the plants which inhabit the low marshy
land on each side the channel, the animals and birds
that are peculiar to low-lying districts, and, above all,
the fishes which swim in the fresh waters, and the
insects which live and die upon their banks. All
these belong especially to rivers and lakes with their
surroundings; but it will at once become evident to
the naturalist that there remains a large aquatic
region, with its own fauna and flora, untouched by
books limited to the sea on the one hand, and to running'waters on the other. The few plants which are to

8

PONDS AND DITCHES.

be found in streams are not the same as those which
choke up stagnant ditches, or flourish in profusion in
ponds, in many of which fishes would disdain to
dwell.
Definitions are unsatisfactory generalizations in
the majority of instances, to which this is hardly an
exception. It is not easy to define in a few words
the area over which our wanderings are intended to
extend; this will become more evident from a perusal
of the whole work. It may be premised, however,
that in commons, marshes, and low districts, there
are miles after miles of ditches which have no perceptible current, only varying in height, not with the
tides, but only with wet or dry seasons; ditches in
which vegetation appears to run wild, three-fourths of
the surface being covered with the leaves of aquatic
plants, or a green scum, and whose dark waters, impregnated with the decay of plants, have sometimes
an unmistakable odour. Such ditches swarm with
living creatures too numerous for more than a small
portion to come under our notice. Then again there
are more recent openings, " turbaries/ 7 straight cuttings made in marshy land by digging out the turf or
peat for fuel. In some counties the mileage of such
cuttings is by no means insignificant. May we not
also to a considerable extent include canals within
the terms of our definition ? certainly it will be conceded that ornamental waters cut out to adorn a
park, or add to the prospect of a mansion, come
within the scope of still waters. Add to these also
ponds and reservoirs, fish-ponds, duck-ponds, horseponds, ponds upon commons, moors,, heaths, or be-

STILL WATERS.

9

side the village green. Wherever there is an expanse
of water not even larger than could be covered with
a blanket, or a ditch no wider than can be straddled
over, if there is no perceptible flow or current, then
we claim for it the definition of " still waters," and
extend over it our jurisdiction. It is not by any
means the largest pond or the widest ditch that
yields the most interesting objects, for a little puddle
on a common scarcely more than a yard square may
be a prolific hunting ground; and if we bear in mind
that we are rambling beside still waters, the limits of
our domain will be sufficiently indicated.
If we confine ourselves absolutely to aquatic plants
and animals, excluding all the vegetation of the
banks, all the birds of the air, all the fishes that
swim, it may be urged that very little is left to us,
either to give interest to a volume, or a ramble,
except very little creatures, and very insignificant
plants. This may be true, but size is no attribute of beauty, and the smallest and meanest
creature that crawls may teach us something. In
all the volumes contained in this series hitherto,
the objects have at any rate been visible to the
naked eye; amongst the animal world, very few
have been smaller than the house-fly, and yet this
insect occupies, for size, about the middle place
in creation. It has been calculated that between
the elephant, as representing the largest animal
known, on the one hand, and the most minute living
creature yet discovered on the other, the middle
position, as regards bulk, between the largest and
the smallest, would be that of an insect the size of

10

PONDS AND DITCHES.

the common house-fly. Surely we know only half
creation if we ignore all beneath this limit, and it
shall be our excuse that, in defence of half the world,
this book is written.
At once it becomes our duty to confess that, although we shall endeavour not to write of animals
smaller than can be seen with an ordinary pocketlens, it is our intention to introduce our readers to a
number of very minute organized beings, creatures
whose whole world is a little puddle of water, who
are born, and die, and leave behind them a progeny
like themselves, and yet their place in creation may
be represented by the punctuation point at the end of
this sentence.
What said Charles Kingsley?—"The zoophytes
and microscopic animalcules which people every
shore, and every drop of water, have been now raised
to a rank in the human mind more important, perhaps, than even those gigantic monsters, whose models fill the lake at the Crystal Palace. The research
which has been bestowed for the last century upon
these once-unnoticed atomies has well repaid itself;
for from no branch of physical science has more
been learnt of the scientia scientiarum, the priceless
art of learning; no branch of science has more
utterly confounded the wisdom of the wise, shattered
to pieces systems and theories, and the idolatry of
arbitrary names, and taught men to be silent while
his Maker speaks, than this apparent pedantry of zoophylology, in which our old distinctions of ' animal,'
' vegetable,' and ' mineral,' are trembling in the
balance, seemingly ready to vanish like their fellows

STILL WATERS.

II

—' the four elements'of fire, earth, air, and water.
No branch of science has helped so much to sweep
away that sensuous idolatry of mere size, which
tempts man to admire and respect objects in proportion to the number of feet or inches which they
occupy in space. No branch of science, moreover,
has been more humbling to the boasted rapidity
and omnipotence of the human reason, or has more
taught those who have eyes to see, and hearts to
understand, how weak and wayward, staggering and
slow, are the steps of our fallen race (rapid and
triumphant enough in that broad road of theories
which leads to intellectual destruction), whensoever
they tread the narrow path of true science, which
leads (if I may be allowed to transfer our Lord's
great parable from moral to intellectual matters) to
life; to the living and permanent knowledge of living
things, and of the laws of their existence."1
At once, then, let us make bold and candid confession that henceforth our interest in a fellow-inhabitant of God's world is not a question of inches,
or parts of an inch, and that magnitude is no criterion of admission into our investigations.
There should be no misconception as to the necessities of rambles of such a description. Those who
go abroad in search of absolutely microscopical objects do not carry a microscope with them, and our
ramblers need not be provided with any other help
for their eyes than a pocket-lens of an inch focus,
carried in the waistcoat-pocket. This will be all that
1

" Glaucus, or Wonders of the Shore," p. 33.

12

PONDS AND DITCHES.

is needed for the work at the pond, but the examination and investigation of all the beauties which these
organisms exhibit implies afterwards the use of the
microscope. Yet, even without the microscope, how
much may be learnt, what interest may be excited ?
A bottle of water-fleas, held up to the light, may
afford considerable pleasure; their jerky movements,
their vivacity, and their mode of life may be seen
and watched even with the unaided eye ; but to count
their legs, to see the movements going on within
their transparent bodies, will require other help.
This is not a plea on behalf of the minute organisms alone, it applies equally to larger animals
and plants. The curious structure of bat's hair, a
bird's feather, a butterfly's wing, the florets of a daisy,
the sting of a nettle, are all hidden from the naked
eye, and no one can claim the title of naturalist who
ignores the use of the microscope. In our closing
chapter, we propose giving such hints as may be
necessary to follow up the investigations to which
the chapters which precede it are only an introduction.
There is little need for apology on behalf of a
volume which comes into existence without a competitor. The nearest approach dates from twenty
years ago, but even this made no attempt to cover
more than a portion of the ground which we have
essayed. In an age of books it is strange that the
rambler beside ponds and ditches should have been
left without a pocket-companion. And now that we
venture to believe in the existence of some who desire such counsel, we cannot but link it with a faith

STILL WATERS.

13

in the ultimate satisfaction which follows from a persistent endeavour to search out the unseen works of
the Creator. The pursuit of such studies, in their
lowest results, is a good school for the exercise of
patience and perseverance, and in their highest, it
brings one into contact with the manifestations of
Divine power, as exhibited in a world hidden from
the uninquiring eye, but withal as wonderful, if not
even more astonishing, than that in which we live,
and move, and which we contemplate with unaided
sight. The student who brings with him a desire to
see the Maker revealed in His works, will never repent having wandered over an untrodden field.
Some of the attributes of the student of Nature are
admirably portrayed by an author already quoted,
and may fitly close this introduction :—" He should
be brave and enterprising, and withal patient and
undaunted; not merely in travel, but in investigation ; knowing (as Lord Bacon might have put it),
that the kingdom of Nature, like the kingdom of
Heaven, must be taken by violence, and that only to
those who knock long and earnestly does the great
mother open the doors of her sanctuary. He must
be of a reverent turn of mind also, not rashly discrediting any reports, however vague and fragmentary,
giving man credit always for some germ of worth,
and giving Nature credit for an inexhaustible fertility
and variety, which will keep him his life long always
reverent, yet never superstitious; wondering at the
commonest, but not surprized by the most strange;
free from the idols of size and sensuous loveliness ;
able to see grandeur in the minutest objects, beauty

14

PONDS AND DITCHES.

in the most ungainly; estimating each thing, not
carnally as the vulgar do, by its size, or its pleasantness to the senses, but spiritually by the amount of
Divine thought revealed to him therein; holding
every phenomenon worth the noting down; believing that every pebble holds a treasure, every bud a
revelation; making it a point of conscience to pass
over nothing through laziness or hastiness, lest the
vision, once offered and despised, should be withdrawn ; and looking at every object as if he were
never to behold it again."1
Kingsley's "Glaucus," p. 46.

PONDS AND DITCHES.

*5

CHAPTER II.
FLOWERING

PLANTS.

who expect to find in marshes and swampy
places the same flowers and plants as are familiar to
them in lanes and woodlands, will be very much disappointed. There is such a marked distinction between the character of the plants found growing in
low swampy places, marshes, and bogs, and those
habitual to pastures, woods, and hedge-rows, that the
young botanist will find himself in presence of as
distinct a flora as if he were to travel to some foreign
country. So many of the usual inhabitants of such
localities are enumerated in a companion volume to
the present,1 that it is our intention to allude only to
those which are thoroughly aquatic in their habits,
that is to say, to plants which will be found growing
in the water of ponds and ditches, rather than to
those which flourish only on their margins. Rivers
and running streams are very deficient in growing
plants, except along their borders, whilst stagnant
waters teem with growing plants of various kinds,
large and small, many being so very minute as to be
almost, or quite, invisible to the naked eye. Flowering-plants, or those which produce conspicuous
THOSE

1

" Lakes and Rivers."

i6

PONDS AND DITCHES.

flowers, are always large enough to be seen. What
an inexhaustible store for investigation will be presented by a single stagnant ditch, choked with
vegetation, such as Norfolk, Cambridgeshire, and
Lincolnshire could furnish.
Almost the first plant which would attract notice

WATER CROWFOOT.

in ponds and some ditches would be the little white

FLOWERING PLANTS.

17

1

flowers of the Water Crowfoot, just peering above
the surface of the water. The leaves are submerged
and very variable, the upper ones being three-lobed, but
the lower ones almost skeletons. The great variability
of this plant has led some botanists to regard many
of the forms as distinct species, but this need not
trouble us, who are content to regard them all as
simply the Water Crowfoot. This plant is so common that it should be at once recognized ; indeed, it is
essential that all the ordinary flowering-plants which
grow in ditches should be readily distinguished, on
account of the large number of minute animals which
will be found adhering to them, so that hereafter we
shall constantly have to refer to the names of plants
which we are now about briefly to describe.
Still more imposing in appearance are the White2
and Yellow Water Lily,3 their large, smooth, glossy
leaves lying on the surface of the water. It has been
asserted that the flowers of the latter have the odour
of brandy, and hence in Norfolk are called " Brandybottle." As far as our experience of Norfolk goes, it
is the flask-shaped seed vessels which are called
" Brandy-bottles," from their resemblance to a flask.
The water-lilies are the noblest of British aquatic
plants, and the under surface of the broad-spreading leaves afford shelter and a home for many a
minute animal. The sacred Lotus of Egypt and
India was a water-lily, and its flowers were largely
employed in the sculptures which decorated their
1
3

2

Ranunculus aquatilis.
Nnphar lutea.
C

Nymphcea alba.

a8

PONDS AND DITCHES.

temples. The Water Villarsia1 is too uncommon a
plant to cause much trouble in its identification. It
lhas somewhat the habit of a small water-lily.

YELLOW WATER-LILY.

There are two very prominent plants in ditches
jfrom their tall erect straggling mode of flowering.
1

Villarsia nymphceoides.

FLOWERING PLANTS.

19
1

One of these is the great Water Plantain, with long
lance-shaped leaves, standing erect on long stalks,

WATER PLANTAIN.

the veins of the leaf running parallel, as in the Common Plantain. The flowering stem is at least 2 ft.
Alisma plantago*
C 2

20

PONDS AND DITCHES.

above the surface of the water, with many long
slender branches, and numerous three-petalled flowers,
which are so delicate that they soon fall away. During
the winter the naked flower-stalks remain standing like
skeleton sentinels in the silent water.
The other plant is most remarkable for the shape
of its leaves. It is the Arrow-Head l with its arrowshaped leaves standing erect out of the water on long
foot-stalks, covering at times
a very large surface, either
alone, or mingled with the
Water Plantain. The threepetalled flowers are rather inconspicuous, but the leaves
are so characteristic that
they are quite sufficient for
the identification of the
plant. Perhaps there are
no more common plants
than these two in stagnant
ditches; both possess farinaceous roots, and those of
the Arrow-Head have been
used as food in times of
scarcity, whilst the Chinese
obtain a meal from them
ARROW-HEAD.
which is commonly eaten.
One of the most beautiful of ditch plants is that
called the Flowering" Rush, 2 but it is by no means
common.
Sagittaria sagittifolia.

2

Butomus umbellatus.

FLOWERING PLANTS.

21

Here we may notice a very insignificant little plant,
as far as size and appearance is concerned, but most
remarkable for its rapidity of increase. This is
sometimes called the American Water-Weed l because
it was introduced from that
country. It is believed to
have come over with some
timber and thus got transplanted into the canal near
Market Harborough about the
year 1847, and from thence
spread over England. Five
years previous to this it was
found in a pond in Berwickshire, from whence it probably made its way in Scotland.
The plant
grows
entirely in the water in dense
masses, with a thin brittle
stem around which the leaves,
.about half-an-inch long, grow
in threes or fours. As only
the female plant is known in
this country, its entire diffusion has been by joints, or
portions broken off, and not AMERICAN WATER-WEED.
by seeds. In 1851 the plant
was noticed in the river between Ely and Cambridge, since which time it has increased so rapidly
that it has become the greatest source of annoyAnacharis alsinastrtim.

22

PONDS AND DITCHES.

ance to watermen and navigation seems almost to*
be arrested by it. The railway dock at Ely became
so choked with it that several tons had to be lifted
out. It is difficult to say where in the three kingdoms
it may not now be found. With its serious faults, it has
also one small feature of utility, since it is one of the
best plants for
cultivation in a
small freshwater aquarium, where it
grows rapidly,
oxygenates the water freely,
and some of our readers may
experience its value if they
desire to carry out the suggestions which occur in our
volume.
Of totally submerged plants
the Pond-Weeds are amongst
the most common. There are
several kinds or species of
them known to botanists by
the name of Potamogeton ; perhaps eighteen or twenty are
found in Britain. One of the
most common is the floating
Pond - Weed.1 The upper
leaves are elliptical, quite flat,
on very long slender stalks,
POND-WEED..
Pbtamogeton natans.

FLOWERING PLANTS.

23

and lie on the surface of the water, as though
they had no plant to belong to. The small green
flowers are produced on a spike which rises above
the surface of the water. There are other species
with long, narrow, grass-like leaves, and others again
with leaves almost as narrow as threads. The
Pond-Weed with opposite leaves,1 has the thin,
almost transparent, green leaves arranged in pairs
along a slender flexuous stem. When the leaves of
some of these weeds are dried they are almost as
thin and delicate as gold-beater's skin. The flowers
are without any attraction, either of colour or odour,
and the plants would scarcely deserve mention did
they not serve as food or shelter to so many aquatic
animals. Entirely covered as are many of them by
the water in which they flourish, they are seldom seen
except when dredged up from their homes by the
botanist, or by the workmen in cleansing the ditches..
Either a walking-stick with a hook or small rake at
the end, or, better still, a few yards of cord with a
small iron hook with three prongs attached, will serve
to bring these and other water-weeds to the shore.
With such an instrument as this, which can be thrown
some few yards into the middle of a pond, sinking by
its own weight, will bring the water-lily leaves, pondweeds, and other plants within range of observation,
otherwise they will remain out of reach, greatly to
the annoyance of the poor wanderer who stands upon
the brink and wonders what may be the treasures
which he sees but cannot touch.
Potamogeton densum.

24

PONDS AND

DITCHES.

The same means which brings the pond-weeds to
the shore will doubtless bring with them also the
following three allied plants, or one of them. The
Mare's-tail,1 which, by-the-by, is
quite different from the Horse-tails,
allied to ferns, and not aquatic
plants. The Common Mare's-tail
has jointed stems, around which
the narrow thready leaves grow
in whorls, or circles radiating like
a star. The Water Milfoil,2 which
has leaves deeply cut into narrow
thready segments and slender
branched stems intertwined in a
tangled mass when drawn out of
the water, in which it grows wholly
submerged. The Horn wort3 has
narrow leaves surrounding the
stem in whorls, or circles, but
these differ from those of the
mare's-tail in being divided two
or three times in a forked manner, forming a more dense mass
of foliage. Any of these three
plants may be found in still waters.
A slender little plant not uncommon in ditches is the Starwort,4 so
MARE'S-TAIL.
called because the little pale-green
leaves are arranged like a star or rosette, at the top
1
3

Hippuris vulgaris.
Ceratophyllum demersum.

2
4

Myriophyllum spicatum.
Callitriche verna.

FLOWERING PLANTS.

25

of the slender stem, and this rosette floats on the
surface whilst the submerged stem has the leaves in
pairs, and long thready roots springing from the joints.
The plant is but slightly attached to the ground, so
that it may be lifted
out of the water
without any perceptible resistance. It
may be seen growing in company with
duckweed, or by
' itself in stagnant
pools, sometimes in
running water.
This reminds us
of the Duckweeds.
Of course every one
knows "duckweed,"
and yet very few
know much about
them. They
are
very small, insignificant plants, and
yet they possess considerable
interest,
for small as they are
they possess
flowers.
HORN-WORT.
We see them floating together by hundreds and thousands on the
surface of still water, like so many little leaves, and
we call them " duckweed," and think no more about
them. There are four species of duckweed found in

26

PONDS AND DITCHES.

Britain, and the differences between them it may be
as well to state at once. The Greater Duckweed1
has the fronds, or little green plates resembling a

GREATER D U C K W E E D AND THICK DUCKWEED.

small leaf, larger than any other species, nearly
circular, rather thick, with a cluster of fibres, like
roots, proceeding from the under-surface. The Lesser
Duckweed2 is the most common; it has small
ovate fronds, generally two or three adhering together,
with one root-fibre proceeding from the under-side of
each. The Thick Duckweed3 has fronds of nearly
the same shape and size as the last, but thicker,
flattened above, and rounded beneath, each with a
single root filament. It grows in the most stagnant
and fetid waters, and is supposed to be uncommon,
though some there are who think it is only a variety
of the Lesser Duckweed. Lastly, there is the Ivyleaved Duckweed; 4 the fronds are nearly half an
inch long, thinner than in the other species, narrowed
1

Lemna polyrhiza.
Lemna gidda.

2
4

Lemna minor.
Lemna trisulca.

FLOWERING PLANTS.

27

towards each end, with a single root filament to each
frond. These are all floating plants; that is, they
are in no way attached to a single spot as most plants.

IVY-LEAVED D U C K W E E D A N D LESSER D U C K W E E D .

but float freely on the surface of the water. There
are no stems, and no real leaves, but the whole plant
consists of a small frond, which resembles a leaf in
appearance, and one or more little threads proceeding
from the under-surface, hang down in the water and
perform the functions of a root, but they do not become attached to anything. The fronds are sometimes separate, and sometimes two or three adhere together. They increase and multiply by young ones
budding out at the sides, or rather the edges of the
full-grown frond. The flowers are very small and
rare, but when produced they grow out of little cracks
or fissures at the edge of the fronds.
A very good plan to adopt for the study of these
curious little plants is to collect them with the water
in which they are found, in a wide-mouthed bottle,
and when safely carried home transferred to an ordinary tumbler-glass, in which they will keep alive and

28

PONDS AND DITCHES.

grow for some time, so that they may be seen budding
and increasing, and flourishing as well as in their
native ditches. 1 A little plant, called Wolffia,2 has
been recognised in this
country only in recent years.
It looks very like a small
duckweed, and grows in
similar situations, but it will
be recognised from them by
the fact of its having no
rootlet proceeding from the
under-surface of the frond.
Thus far the plants which
we have enumerated are
DUCKWEED, SHOWING
MODE OF GROWTH.
chiefly confined to still
water, and many of them are
entirely aquatic. There are, however, some others
which must be mentioned in order to render our
catalogue at all complete, which are not confined exclusively to ponds and ditches, but are commonly
found there.
The most important of these additional plants is
the Common Reed, 3 which is seldom absent from
still waters or sluggish streams, growing under favourable conditions to a considerable height, and often
extending for many acres, forming large " reed beds "
in fenny districts, as in Norfolk and Lincolnshire.
Those large expanses of water known to Norfolk
people as the " broads " are spots which ever live in
1
3

"Science-Gossip," January 1st, 1865.
Phragmites communis.

2

Wolffia arrhiza.

FLOWERING PLANTS.

29

the memory of the naturalist who has frequented
them. Here the reeds and their inhabitants may be
seen in their best aspect. One who knows them well

COMMON REED.

has thus written in their praise. The lavish notes of
the Reed Warbler " are thus associated in my mind

3°

PONDS AND DITCHES.

with many a calm summer's night on the open broads
the stars shining brightly overhead, and the soft breeze
sighing through the rustling reeds, mingled with the
hum of insect life on the water. It is at such times
that the song of these marsh nightingales is heard to
perfection. All is still around, save those murmuring
sounds that seem to lull to sleep ; the barking of the
watch-dog has ceased in the distance, and the hoarse
croak of the coot or the moorhen, harmonizes too
well with the scene to startle with its frequent repetition. Presently, as if by magic, the reed beds on all
sides are teeming with melody ; now here, now there,
first one, then another, and another of the reed birds
pour forth their rich, mocking notes, taken up again
and again by others; and still, far away in the distance,
the same strain comes back upon the breeze, till one
is lost in wonder at their numbers, so startling to the
ear of the stranger, so impossible to be estimated at
all during the day. I can imagine few things more
delightful to the out-door naturalist than his first introduction to the broads by night. The mere escape
for a time during the height of summer from the heat
and bustle of a city life might alone repay the trouble
of a visit, were there no further attractions in those
sights and sounds which have for the naturalist a
peculiar charm." And thus he concludes :—" Wrapt
in the enjoyment of these rural sounds, one glides
gently down the stream towards the entrance of the
broad; the soft breeze rustles amongst the feathery
reed-tops and the light foliage of the willows by the
river side, the wide expanse of water glows with the
reflection of the setting sun, whilst the rippling waves

FLOWERING PLANTS.

31

upon its surface dance and sparkle on their way, as
though hastening onward to those quiet shades where
twilight, stealing over the landscape, speaks of sleep
and rest for the weary."1
But reeds are not the
only grasses that love the
water, there are, at least,
two others which should
be mentioned as especially
aquatic. The Flote-grass,2
with its long leaves floating on the surface of the
water, and its long slender panicle bending and
waving above them. The
small seeds of this species,
it is said, were collected
and used by the Russians
as food, under the name of
" Manna-croup," although
the modern manna-croup
of commerce is only an
imitation of the rarer commodity. Another species
of the same genus,3 with
erect panicles, grows in
similar places. One or
other may often be seen
growing near the margin
FLOTE-GRASS.
of a pond.
1
2

Stevenson's " Birds of Norfolk," i. p. 118.
3
Glyceriafluitans.
Glyceria aquatica.

PONDS AND DITCHES.

CATABROSA.

The Water Whorl-grass1 has a much more
spreading panicle than either of the foregoing, and is
a noble grass when growing in perfection, but it
Catabrosa aquatica.

FLOWERING PLANTS.

33

shares the fate of all grasses with the young botanist,
that of being thrust aside as " only a grass;" and
even many of those who are no longer young will
not take the trouble necessary to understand the
grasses.
Ponds with a muddy bottom will contain also the
" Black-weed" l or " Bur-reed," of which there are
two species, differing chiefly in the flowering stem
being either branched or simple. The leaves are
long and sword-shaped, and the flowers (afterwards
also the fruit) are collected in globose heads. We
have generally observed that the presence of this
plant indicates a black, oozy mud at the bottom, in
which it grows. Old anglers in the " broads " who
loved the reeds always shunned the neighbourhood
of the "Black-weed," as it was called, because it
flourished in a black, stinking mud, which even fishes
did not approve.
The Reed-mace, or Cat's-tail, is of two kinds, principally to be distinguished by their size, and hence
called the Greater Reed-mace 2 and the Lesser Reedmace. 3 They will reach a height of six feet, and
are conspicuous from a distance by the dark, clublike spike, which grows at the end of the straight
cylindrical flowering stem. This club is at first a
dense mass of the female flowers, the male flowers
being yellow, and growing above them. Finally, the
whole of the spike contains seeds with a downy crest
which aids in their dispersion. When fully ripe, if

3

Sparganium ramosum and S. simplex.
Typha angustifolia.
D

2

Typha latifolia.

34

PONDS AND DITCHES.

one of these clubs is
broken, it soon becomes
converted into a light
puffy down by the expansion of the crests,
and in this state the
cottagers use it as a
stuffing for pillows. It
is a curious fact, that
both in New Zealand
and Northern India the
pollen of either this, or
a very nearly allied species, is collected by the
natives and made into
cakes and eaten.
The BulrushJ is often
found in company with
the Reed-mace. It is
like a gigantic rush, as
thick as the little finger,
and nearly six feet
high. Large quantities
are grown in marshy
districts, in shallow
water, and are cut in
the autumn, by men in
flat - bottomed
boats,
dried and manufactured
into matting, baskets,
REED-MACE.

Scirpus lacusiris.

FLOWERING PLANTS.

35

horse-collars, and other articles, so that in some
villages it is an important branch of industry. The
bulrush of Scripture is not this plant, and mustt
not be confounded with it. The bulrush of the
Egyptians is said by some authors to have been the
papyrus which was employed for writing upon after
the manner of paper. This could hardly have been
the case. The right of growing and selling the
papyrus belonged to the Government, it was a monopoly, and the plants were rooted up in all places
except those under Government supervision. The
monopoly so increased the price that persons in
humble life could not afford to purchase the papyrus
for writing purposes. When Pliny says that the
papyrus had many uses, and that the Egyptians even
" constructed small boats of the plant," he probably
confounded some similar plant of inferior value with
the hieratic papyrus. It is probable that, as Sir
Gardner Wilkinson has suggested, that boats were
made of rushes, bound together with papyrus, or the
fibrous portion of the papyrus, rendered impervious
to water by a coating of pitch. It is of little consequence what particular kind of rush was employed,
whether or not it was that superior kind which was a
monopoly of the Government, and used for writing,
or a commoner kind of rush; there is no doubt that
boats were made of rushes in Egypt, and that they
were coated with bitumen, or some other substance,,,
which rendered them impervious to water.

D 2

3$

PONDS AND DITCHES.

CHAPTER III.
PLANTS WITHOUT FLOWERS.

FOR the sake of convenience we associated together
in the previous chapter all plants bearing evident,
or conspicuous flowers, such being usually termed
" Flowering Plants." There remain, however, a few
which occur in our localities, belonging to what
botanists term the " higher cryptogams ": plants which
do not bear conspicuous flowers, but are reproduced
by means of organs, in which some only of the
characteristics of perfect flowers are present. The
limits and distinctions of these groups will be found
in any good botanical manual.
The number of plants, with aquatic habits, which
belong to the intermediate families, between flowering
plants and Algae, is small, but they could not be
omitted altogether, as they are some of them found
in no other situations, and hence would be excluded
wholly from these volumes. It forms no portion of
our creed, that sound information on scientific subjects
cannot be communicated except in strict scientific
sequence, and in true systematic order. Nevertheless,
where and when a general adherence to definite
groups is a manifest advantage both to author and
reader, it would be folly to relinquish the advantage.
In the present instance, the division adopted serves

PLANTS WITHOUT FLOWERS.

37

to associate together kindred plants, and facilitate
reference to them, when the plan of grouping is
comprehended.

QUILL-WORT (Isoetes hystrix).

.38

PONDS AND DITCHES.

Ferns are not aquatic; although the Royal Fern is
so nearly a plant of that character, that it flourishes
best in swampy places, and is often planted as an
aquatic in artificial waters. Of plants kindred to the
ferns the Little Quill-wort1 is often to be seen covering
the bottom of lakes over a very considerable area,
but confined to mountainous districts. The horny
leaves have to the eye an appearance similar to some
grasses in form, but far different in texture, growing
erect in small tufts with the fruit, about the size of a
pea, hidden under the bulging bases of the leaves.
One or more species flourish so plentifully in the
lakes of Cashmere that the seeds float like a scum
on the surface, and are collected by the natives and
employed in medicine.
The Pill-wort,2 or Pepper-grass, is not so completely
immersed, but prefers the margins of lakes and pools,
in tolerable plenty in some places, but, like the quillwort, it is local. The stolons, or creeping stems,
extend for a considerable distance, sending up here
and there small tufts of slender, grass-like leaves.
The capsules are about as large as a peppercorn, and
grow in the axils of the leaves upon the stolons.
These are both curious plants, and on account of
their habits are known to few except botanists.
Some of the Horse-tails are often to be seen growing
an the water of ditches, but they are not so truly
aquatic as the plants to which we have confined our
observations. The Greater Horse-tail is the most
water-loving species, and furnishes an interesting
,l

Isoetes lacustris, and Isoetes hystrix.

2

Pilularia globulifera.

PLANTS WITHOUT FLOWERS.

39

-object for study, not only in its ribbed flinty stems,
but also in its spores, and the manner in which they
are produced.
Far more delicate plants, always wholly submerged,
and very different in appearance, have been regarded
by some as nearest of kin to the Horse-tails. By
others they are associated with the Algae. Sometimes
included in one group, and sometimes in another, it
will be conceded that there must be some reason for
this uncertainty, and that this reason is associated
with important features in the structure of the plants
themselves. This is indeed the fact, for the plants
alluded to grow submerged like Algae, with brittle
joints, slender branches, and no leaves, like the
Horse-tails, without true flowers, but with substitutes
for flowers, unlike those of any other known plants.
In clear ditches with a muddy bottom these plants
may be seen growing to the height of a foot, in
clusters as much in diameter, composed of threadlike
stems very much branched, with equally threadlike
branchlets growing in whorls or circles around the
stem. In lifting them from the water some are so
fragile that they have a tendency to break up into
joints, all are delicate, and require careful handling.
These plants are known to botanists as the Characece, they have no true flowers and yet they much
resemble some flowering plants, whilst the curious
fruit grows at the base of the tufts of leaf-like
branchlets unlike that of the Algae. They are a sort
of outside group which do not harmonize with any
other, so that they are kept by themselves, and only
known as the Characeas.

4Q

PONDS AND DITCHES.

We have spoken of the leaves as surrounding the
slender stems in circles, but this is no accurate term
as applied to these plants, for they are not leaves, but
branches, which are themselves again branched or
subdivided. The Characeae have no veritable leaves,
although the ultimate branches very much resemble
leaves and perform the same functions. There are
two kinds, or genera, of these plants; in one called
Nitella the stem is a single-jointed tube, the other
called Chara has a central tube and smaller ones
arranged around it. One has, therefore, a simple
stem, and the other a compound one.
It may be remarked here that some years ago we
gathered one of these plants entire from its native
ditch, with the roots attached and a little adhering
mud. It was taken home and planted in an inverted
propagating glass about twelve inches in diameter,
some small pebbles covered over the roots and around
the bottom so as to keep it in position, and the glass
filled with ordinary " supply " water. It soon became
established, grew vigorously until the whole glass was
filled, produced its singular fruits, and continued to
thrive for upwards of three years until the glass was
accidentally broken, and it came to an untimely end
During the whole of this time the water was perfectly
clear and fresh, although it was never changed, or
aerated. Additions were made to compensate for
evaporation, but it was a perfect aquarium, not
requiring the least attention, and the stagnant water
was kept thoroughly pure by the action of the plant
itself. We have tried other plants and combinations
of plants for like purposes, but this is the only

PLANTS WITHOUT FLOWERS.

NITELLA.

41

42

PONDS AND DITCHES.

instance in which the purity of the water was maintained.
Of Chara and Nitella there are about sixteen
British species, some of which are scarce and others
common, but their minute distinctions and differences
would scarcely interest our readers. They will
readily be recognised growing in perfectly clear and
motionless ditches by their pale green colour and
thread-like ramifications. To remove them entire
will require care. Some weapon, such as a hooked
stick, passed round the roots so as to remove them
from the mud, then drawn carefully to the shore and
lifted out, keeping the roots foremost, and all the
branches hanging towards the crown, will usually
prove successful. An established plant will constitute a good aquarium in which the minute aquatic
animals may be kept under constant observation.
Mosses are scarcely aquatic, although some species love to grow beneath the spray of water-falls, on
moist dripping rocks, and in some instances, as in that
otFontinalis, wholly submerged in rapid streams.1 The
Bog-mosses3 are an exception not only to mosses, in
the nature of their fructification, but to the generality
of them in their habits. They delight in bogs and
swamps. Elevated moors abound with them, and
some common forms are found in every swamp.
The Bog-mosses having received no attention in
other volumes of this series, we may be excused for
1
Certain species of Hypnum are great lovers of water, as
H. fluitans, fluviatih) irriguum, &c.
Sphagnum.

PLANTS WITHOUT FLOWERS.

43

regarding them as pond-plants and bringing them
under our own jurisdiction. As they are now treated
as distinct from the true mosses by the bryologists, we
may assume that there are good reasons for doing so,
and proceed with them without drawing comparisons. They are large, pale-coloured, erect plants,
sometimes a foot long,
usually less, growing
closely packed side by
side in dense masses,
often many yards in
extent, in swamps, the
lower portion in clear,
still water, which, however, must be comparatively pure. A handful
taken out from such a
mass is found to be
saturated with water like
a sponge. Place your
foot on such a treacherous spot, and down it
goes amongst water and
mud, with no firm bottom to be found.

Sepa-

SQUARROSE BOG-MOSS.

rate one plant from the
rest, and note the thin, tough wiry stem, the short
branches spreading in all directions, more compact
above, until the summit is crowned by an elegant
rosette. The branches are entirely covered with
scale-like, imbricated leaves. When in fruit, the little
oval capsule stands erect on its peduncle, which

44

PONDS AND DITCHES.

springs from one of the uppermost branches. This
is the general appearance of one of the bog-mosses.
It would scarcely come within our province to
enter fully upon the structure, development, and
reproduction of these organisms; nor is this so much
to be regretted, since Dr. R. Braithwaite (than whom
no one is more competent for the work) has elsewhere most clearly and thoroughly exhausted the
subject,1 and described fully all the European species.
Those who possess a microscope will find in the
leaves a very pretty study. The cellular network
forming sigmoid areolae, and the delicate spiral or
ring-like fibre of the cells, with the intercellular ducts,
containing a coloured endochrome. Nor will the
spores be without interest, for they are of two kinds,
the large tetrahedral macrospores, and the smaller
globose microspores.
Sometimes the spores will
germinate in the capsule when placed in favourable
conditions.
The spores which germinate in the
water develop in a different manner to those which
germinate upon damp earth. Under the latter condition they will germinate in from two to three
months.
And what are the uses of these bog-mosses, or, as
the Germans call them, " Turf-mosses " ? To this
Professor Schimper answers, " Unless there were
bog-mosses, many a bare mountain ridge, many a
high valley of the temperate zone, and large tracts of
the northern plains, would present an uniform watery
flat, instead of a covering of flowering plants or
" Monthly Microscopical Journal," vols. vi. to xiv.

PLANTS WITHOUT FLOWERS.

45

shady woods. For just as the sphagna suck up the
atmospheric moisture and convey it to the earth, do
they also contribute to it by pumping up to the
surface of the tufts formed by them the standing
water which was their cradle, diminish it by promoting evaporation; and, finally, also, by their own
detritus, and by that of the numerous other bogplants to which they serve as a support, remove it
entirely, and thus bring about their own destruction.
Then, as soon as the plant detritus formed in this
manner has elevated itself above the surface water, it
is familiar to us by the name of " turf," becomes material for fuel, and all sphagnum vegetation ceases."
These are not the only uses of these plants,
although those in our minds are infinitely smaller in
their relationship to the great scheme of nature than
the reclamation of waste or the manufacture of peat.
Yet we cannot forget how much the naturalist is, in
his way, indebted to the masses of sphagnum which
shelter so many minute organisms. The bryologist
confesses to the presence of infusoria within the cells
of the leaves, but who can enumerate the creatures
which sport outside, the water-fleas, the wheelbearers, and small snails ; the confervoid algae, which
adhere sometimes in such quantity that the water
which drips from a lifted tuft is redolent with minute
vegetable as well as animal life.
Of the seventeen British species some are rare,
others local in their distribution; whilst others
again, are common. For us, who do not profess to
be critical moss-hunters, the common are as attractive
as the rarest; in the ubiquitous blunt-leaved Bog-

46

PONDS AND DITCHES.

moss 1 we have all the materials for the study of
structure and development, and in that we can read
what bog-moss really is, as satisfactorily as in that
very rare species (if there be such an one) which is
found but once in a hundred years.
There is with us a strong reason why the bogmosses should be recognised, and that is, that
desmids and diatoms are often to be found growing
upon them, and hence they will often be alluded to
for other reasons than their own individual merits.
The aquatic plants most kindred to the mosses
are two species of minute plants found floating on the
surface of standing water,
mixed with duckweed, but
larger, though in some points
similar. These belong to what
are called the Liverworts, or
Riccia Jluitans, nat. size.
rather to that section called
crystal worts. The half-dozen
British species of Riccia include only two really aquatic ;.
one of these has fronds from
one inch in length,2 repeatedly
forked, so that the divisions
form narrow segments, slightly
„. . „ .,
A.
r notched at the end, of a yelRicaajluitans, section of
sporangium.

lowlsh

'
,g reei ^ colour.

*
The

sporangium is globose, and
protuberant on the under side of the frond.
Rootlike threads proceed from the under-side
Sphagnum cymbifolium.

2

Riccia Jltritans.

PLANTS WITHOUT FLOWERS.

47

of the frond, but these are not attached to
anything as the plant floats freely, mixed with
duckweed, on the surface of stagnant pools and
ditches. The other species differs from the above in
the essential particular that the sporangia are immersed in the frond and not
protuberant on either surface beyond a slight indication of their
presence.1 The fronds are about
half-an-inch in length, slightly
grooved in the centre, inversely
heart-shaped, and pale green on
the upper surface. The margin
and under-surface are clothed with
numerous pendent rootlets of a
purplish colour. It is sometimes
abundant in boggy pools,floatingon the surface of the
water. Both these will grow readily in pans of water,
or on the water of an aquarium, for which purpose
they are most desirable objects.
What are termed by botanists the Lower Cryptogamia, consist of Lichens, Fungi, and Algse. The
latter are, of course, well-represented in still waters;
but the former absent, except in the case of those
fungi which are parasitic upon fish, frog-spawn, dead
insects, &c, and called the Saprolegnice. Who has
not observed dead flies adhering to the window in
the autumn, their bodies covered with a frosty white
powder, and the same substance adhering to the glass
beneath and around them? These poor flies have
Riccia natans.

48

PONDS AND DITCHES.

fallen a victim to a parasitic mould l which never
advances beyond a very simple condition on the flies
in the air, but should the flies fall into the water or be
thrown into it, then a much more elaborate developement is given to the mould; fine threads radiate into
the water in all directions, and the fly becomes the
centre of much such a thready white mass, as forms
upon fish, and bears the name of " fish mould," or
" salmon disease." Not only apparently, but really is
it the same kind of thing. That which was a very
simple mould, whilst the fly was in the air, developes
into one of the Saprolegniae when the fly gets into
the water.2 Undoubtedly the one mould is only a
condition of the other. The fungi differ from these
aquatic moulds, especially in not being inhabitants
of the waters. We are prepared, therefore, for the
Algse, and with them another chapter.
Emptisa muscce.

2

Achlya firolifera.

PONDS AND DITCHES.

49

C H A P T E R IV.
FRESH-WATER ALGJE.

UNFORTUNATELY we have not in use any word which
corresponds to "seaweeds," as applied to similar
plants growing in fresh water. Everyone at once
will recognise what is intended when the Marine
Algae are called seaweeds, but it is not every one
who could comprehend the scope or intentions of
such a phrase as "Fresh-water Algae." Neither
would "Confervae" be sufficiently comprehensive,
because so many of the Algae of fresh waters are by
no means Confervae. The only alternative seems to
be the adoption of a word, or phrase, which characterises the plants intended to be included, even
though it may not be a phrase in common popular
use.
It can hardly have escaped notice that sticks,
leaves, rushes, and even stones and rocks, which are
immersed in water, soon become covered with tufts of
greenish threads, sometimes so minute as to resemble
a mere cloudiness of the water, at others forming
distinct velvety or long thready tufts. These are
some of the fresh-water Algae, and it is only when
magnified that it can be seen what differences there
are between them, not only in thickness but also in
E

50

PONDS AND DITCHES.

the arrangement of the green substance, or endochrome, to which the general green appearance is
due. Of course, there are some fresh-water Algas
which float freely and are never attached, but it is
more particularly to the tufted, or filamentous kinds,
that we would first direct attention, because they are
the most conspicuous, and would be the first to be
recognised.
Conferva is a very vague term which has been applied to almost any threadlike filamentous plant
found growing in water or damp situations. At one
time it included plants of widely diverse character, to
which other names have been since applied; but even
now it is very usual to call all the threadlike Algae
which grow in fresh water by the general name of
Confervse. They have been very little studied in this
country, and the latest book specially devoted to them
is nearly forty years old.
The first type which is likely to be met with in
exposed pools during summer and autumn is that
called Sfl'rogyra, in which the filaments are of a
bright green colour, and from a fractional part of an
inch to nearly a yard in length, composed of cylindrical cells joined end to end. In streams they
attach themselves to weeds, and wave in the current
like a green fringe, but in quiet pools they usually
float on the surface unattached, in green or brown
patches. " When viewed under the microscope, with
a power of one or two hundred diameters, the bands
of chlorophyll, or green colouring matter, are seen
disposed in various elegant spirals. In some species

FRESH-WATER ALG.E.

51

these bands are single, in others there are two, three,
or four. Upon these bands, which are generally
slightly jagged along their edges, are grains of brighter
green, disposed at pretty regular intervals, and adding
greatly to the beauty of the plant. Sometimes the
larger grains are surrounded with smaller
ones, and the bands appear like two
festoons of exquisite green flowers."
The phenomenon of conjugation may
be well observed in these Algae. Two
neighbouring threads meet, and throw
out from their sides little processes
\A
which at length unite, and the cell
walls become absorbed, the contents of
one cell pass into the other. During
this process the spiral coils are relaxed,
J\
the symmetrical arrangement of the
endochrome is disturbed and lost, and
when the conjugation is complete the
combined contents of the two conjugating cells become an oval spore from
which ultimately a new plant, like its
parent, is developed.
Zyguema is another group of very
•similar plants found growing in like SPIROGYRA.
situations, but the green contents
instead of having a spiral arrangement, assume the
form of two star-shaped bodies, or two globose
masses in each cell. Conjugation takes place as it
does in Spirogyra, the chief difference between them
being in the arrangement of the endochrome. There
E 2

PONDS AND DITCHES.

52

are other forms, called by long names, in which the
endochrome is arranged in two transverse bands, 1 or
with the cell contents diffused.2
There is an abundance of a
branched Conferva3 found attached
to stones, piles, and other objects,
but mostly in running streams,
which exhibits another aspect in
the history of the fresh-water Algae.
At certain times the whole of the
endochrome contracts and becomes
^Jj
broken up into a large number of
small bodies, called zoospores, each
ofwhich is furnished with two moveable cilia at one end. Swarms of
these zoospores, produced in the
manner we have stated, escape
through orifices in the walls of the
Conferva into the water, wherein
they move freely with considerable
agility. At one time these zoospores were believed to be confined
to the Algae, but they are now
known also to prevail extensively
in fungi. Not only does the potato
disease maintain its hold chiefly
through the great number anddiffuZOOSPORES.
sibility of the zoospores, but also the
disease to which fish are subject,
including the form known as the " salmon disease," 4
1
3

Zygogonium.
Cladophora glomerata.

2
4

Mcsocarpus.
Saprolegnia.

FRESH-WATER ALG.1E.

53

are dependent for their increase upon the
myriads of zoospores which are produced.
The immense amount of writing which already has been perpetrated in this country
upon the subject is not only incomplete,
but comparatively useless, from a want of
appreciation of the methods by which the
mould reproduces itself. It is amusing to
read learned dissertations, compiled from
foreign authors, in which no practical acquaintance with the subject can be traced,
and from which the most important features
are studiously omitted.
The genus Ulothrix is another example
of a Conferva which freely produces zoospores. The species are of common occur- &
rence in clear ponds, as well as running
waters, the long streaming green threads
being attached to stones and other objects.
There appears to be a long investing cell,
or sheath, in which shorter cells are packed,
end to end, in a beaded manner. These
cells contain an endochrome enclosing
granules of a darker colour. Arrived at
maturity they may be seen to increase by
division. The cell contents also divide
into eight portions, each portion being
converted into a ciliated zoospore, which
escapes by the rupture of the cell-wall.
After moving about in the water a little UL0THRIX i
time these zoospores become passive,
1

The letters a indicate the cells in process of division.

54

PONDS AND DITCHES.

lose their cilia, and commence growing, by lengthening;
gradually, becoming cylindrical, throwing divisions
across so as to separate the cylinder into joints or
cells, and at last becoming a confervoid thread, like
its parent.
Dr. Hicks has shown, as the result of careful investigation, that even amongst the filamentous Algae
the same plant has received different names at different
periods in its development. Particularly, has he indicated that the thread-like form called Lyngbya, at a
further stage of segmentation, or division of the endochrome, becomes what has been named Schizogonium^
and that the ultimate, or adult condition, has received
the separate name of Prasiola. " The only real
difference," he says, " between the first two is that
whereas Lyngbya is a tube containing distinct cells
within, which when old undergo collateral subdivision
to form a band of two, four, or eight rows of cells0.
Schizogonium is a band of two or eight rows of cells,
which when young was but a single row, contained in
a tube; which is only two different ways of stating
the same facts. The comparison of the last two is of
the same kind. For as Prasiola when old, is composed of many rows of cells, but which arose from
a single row, there must have been a time in its life
when it had two, four, or eight rows, and thus have
been a Schizogonium, for there is no other structural
difference between the two."1 We cannot too strongly
insist on this same writer's final dictum. " The study
1
Hicks " o n Lynghya" in "Quart. Micro. Journ." 1861, p..
163. Also " Popular Science Review," vol. vi. p. 1..

FRESH-WATER ALG^E.

55

of the entire life-history is the only means towards
the solution of the value of species."
Some apology is needed for this brief digression
in favour of a subject rather beyond the scope of a
volume such as the present. Were it not for this
feeling the observations might have been extended
considerably. The conclusion is that until we know
more of the life-history of the common fresh-water
Algae we cannot affirm with any certainty whether one
may not be a condition of another, or what relationship they may bear not only amongst themselves, but
also to plants of a higher organization.
More complex and branched forms of these waterweeds are represented by Draparnaldia, 1 found in low
running
streams,
and in ditches, adhering to sticks and
stones. When first
removed from the
water it presents the
appearance of a
mass of coloured
jelly, but on immersion again the
branches expand.
It will dry well
DRAPARNALDIA.
when laid on paper,
and recover its form again to a considerable extent
when afterwards immersed. The plant is composed
of a principal trunk, formed by a series of large cells,
Draparnaldia glomcrata.

56

PONDS AND DITCHES.

placed end to end, each occupied with a ring of green
matter. Branches arise from the junction of these
cells, formed of articulated branched threads, which
are slender, and terminated by a hair-like filament,
much more gelatinous than the simple forms above
described.
Chaetophora is a similar branched Conferva, but it
differs in the filaments being immersed in a gelatinous
matrix. One species is common in slow-running
streams, 1 and another equally, or even more, common
in stagnant waters.2 The tufts are very minute, so
that it may easily be overlooked. The mode of
branching resembles that of a stag's horns.
Here may be mentioned the peculiar little discshaped bodies so common in fresh-water pools, which
attach themselves to leaves, sticks, and the larger
Confervae. As it has no popular name we are compelled again to revert to the scientific, which in this
instance is Colceochete.3
Although so minute, the discs may be distinguished
by the naked eye, the green colour being conspicuous
upon the discoloured plants to which they attach
themselves. The forms are roundish, scarcely a line
in diameter, formed of filaments radiating from the
centre, forked towards the end, and so closely applied
to each other as to appear to be glued together. The
filaments are divided into cells, from many of which
arises a slender tube, out of this projects a long
threadlike filament. Such is the curious structure of
this minute plant, which was first found in Normandy
1
3

Chcetophora endivcefolia.
Colceochete scutata.

2

Chcetophora elegans.

FRESH-WATER ALG^E.

57

growing on the Burr-weed and Pond-weeds, but has
since been seen on a variety of aquatic plants, and
will grow freely when transferred to an aquarium.

There are other forms of discoid Algae, and
especially a pretty little one called Phyllactidium1
which was first found in this country a few years ago,
but probably only another kind of Coloeochete. We
must pass on to one of the great favourites of pond
collectors,, and, notwithstanding its long and pedantic
1

"Science-Gossip," 1867, p. 178.

58

PONDS AND DITCHES.

name of Batrachospermum, 1 one that highly merits
the esteem in which it is held. The most usual
species is very variable in colour, sometimes verdigris
green, or purple, or violet, or nearly black. The
plants consist of delicate branched filaments, from
one to three inches in length. Around the branches
at regular distances grow
dense whorls of moniliformy
or beaded threads, mostly
branched, forming large
conspicuous tufts.
The
spores are produced in
large numbers in each tuft.
No verbal description can
give an adequate idea of
the beauty of the radiating
tufts of beaded cells, as
seen under the microscope.
The plant mostly delights in moving waters,
but is occasionally found
in nearly still water, proBATRACHOSPERMUM.
vided it is clear and pure.
It is often attached to the
shells of fresh-water snails. Bory, who carefully studied
these plants, gives the following curious fact regarding
them: " I t is upon individuals of this variety (confusuni)
that I made for the first time an experiment which
ought to be known ; after having many times carried
1
Batrachospermum moniliforme; the meaning of the generic
name of Batrachospermum, is "frog-spawn."

FRESH-WATER ALG^E.

59

from one locality to another stones bearing individuals
of this species, which continued to prosper in spite of
the change of habitation, I steeped many of them in
lukewarm water, afterwards in boiling, and no part of
the Batrachosperm appeared, under the microscope,
to have undergone the slightest disorganization by
these immersions, and certain sprigs replaced in their
native place continued to vegetate after these experiments. I do not think that there exist other vegetables
which boiling water does not immediately disorganize;
there are not others that can resist temperatures so
opposite."
However necessary it may be to give some brief
account of the features which these organisms present
to the eye, in order to facilitate their determination
and give an interest to specimens which may be found,
it is by no means attractive reading, and too free an
indulgence would give reasonable cause for complaint
against a book of such small pretensions. Hence we
will rest content with another group of the genuine
Confervae, and then pass on to other Algae.
The (Edogoniacece is a group, the name of which
has almost become classical, on account of the large
amount of literature which has been devoted to it.
Some of the species are amongst the commonest and
most abundant of fresh-water Algae, being found in
every pond, ditch, or stream, and soon even making
their appearance in aquaria. The entire structure
and economy of this group would occupy too much
of our space, so that we must content ourselves with
referring at footl to places where further information
1

Dr. H. Wood, "Fresh-water Algae of the United States,"

6o

PONDS AND DITCHES.

can be found. " They are small filamentous plants
whose size is sufficient to render them visible to the
naked eye, and yet not sufficient to make each individual distinctly apparent. They grow mostly in
quiet water, attached to almost any and everything
that can afford a foothold, fringing with apparent
indifference stones, twigs, sticks, dead leaves, bits of
glass, boards, &c. We have seen such masses of
them crowding the whole surface of a small snail-shell as
to entirely conceal the animal
and its shell, and present the
curious spectacle of a perambulating waving forest of
bright green."
They are generally to be
recognised by their dense and
uniform green endochrome.
sometimes filling the cells,
sometimes retracted and leaving halfthe cell colourless, and,
above all, by the ringed lines
or striae at the ends of many
of the cells. In some the
filaments are unbranched, 1
in others the filaments are
branched, armed with bristles
BULBOCHVETE.
having a bulbous base. 2 They
have all a complex system of reproduction by active
p. 190; " Micrographic Dictionary under (Edogonium " ; and
the works of De Bary, Thuret, Pringsheim, and others.
1
2
(Edogonium.
Bulbocluzte.

FRESH-WATER A L G J E .

6I

zoospores and by resting-spores, which latter rest
during the winter and germinate in the following
season.
Common species of Cladophora and Oscillaria will
be found in every pond, and probably altogether not
less than four hundred different kinds of Algae in the
British Isles, exclusive of the desmids and diatoms;
so that our notice of them is essentially fragmentary.
In the whole circle of pond-life there is no more
interesting
object
than that called
Volvox. It is found
sometimes in considerable numbers
in clear ponds, and
though so minute
as to measure only
one-fiftieth of an
inch in diameter,
yet when a bottle
of water containing
them is held up
VOLVOX.
against the light
these little bodies may be seen by the naked eye as
little movable green spots. This little organism when
seen under a low power of the microscope is found to
be a globe of transparent membrane of a delicate
green colour, marked with fine lines in the form of
network, with darker green spots at the points where
the lines cross each other. Smaller, but similar,
spheres may be seen rolling about within this parent
globe. By means of a constant rolling motion the

62

PONDS AND DITCHES.

Volvox glides gently through the water, or rather
revolves within it, its young ones meanwhile revolving within itself. When viewed under a still higher
power of the microscope the green spots at the meeting of the lines are found to be clusters of delicate
hairs, and doubtless it is owing to their action that
the Volvox rolls through the water.
If by means of pressure between the glasses by
which it is exhibited the sphere is broken, the outer
membrane will be seen to resolve itself into a number
of small cells, each with its bunch of hairs, and each
cell capable of spontaneous motion in the water. For
a long time it was considered as a low form of animal
life, and was mixed with a heterogeneous company
under the name of Infusoria. In these latter days it is
grouped with the Algae, and though endowed with the
peculiar motion to which we have alluded, there is no
reason why it should be considered an animal on that
account, since zoospores with movable cilia are not at
all uncommon amongst undoubted plants. Finally,
when the old Volvox breaks up, the young ones
escape from their temporary prison and float away on
their own account, grow to the size of their parent,
and enclose little rolling balls within themselves, as
did their progenitor.
There are still points of obscurity about the history
of these spheres : what becomes of them in winter ?
in what form and where do they rest ? Do they produce the bodies called resting spores ? These are questions still to be answered. It has always been rather
difficult to preserve the Volvox after it has been collected j they seem to dislike confinement. Recently,

FRESH-WATER ALG/E.

63

however, a successful experiment has been made,
which is thus recorded :—"For several years the writer
used to place the Volvox in large glass or earthenware
jars, small bottles, open dishes, and other vessels exposed to full sun, or kept in partial or entire shade,
supplying it with rain, pond, and spring water in turn,
but always with the result that after a short time it
disappeared. In October, 1878, however, he put a
small quantity, probably not more than one hundred
individuals, in a four-ounce bottle, having a mouth
three-quarters of an inch in diameter, and set this on
a shelf at the side of an out-house which had no
gutter, so that the rain in running off the roof would
drip into the bottle ; here it remained until November,
1879, and instead of the few original specimens, they
had become abundant. The water had never been
changed or replenished, only that which dripped
naturally from the roof into the bottle having been
added to the original stock, and during the abundant
rains of the year the bottle often overflowed. Several
times a portion of the water containing the Volvox
has been placed in the jars and dishes standing in
various parts of the garden, but these always died in
a short time, whilst those left in the small bottle
remained in perfect health and multiplied.
The
position in which the bottle was placed faced the
north, so that it only got the sun in the early morning
of the summer months. During the severe weather
of the previous winter (1878-9) the water was several
times frozen into a solid mass of ice, but apparently
without injuring the Volvox." l
1
N. E. Brown in " Gardener's Chronicle," 1879, p. 599.

64

PONDS AND DITCHES.

There is another, but smaller, nearly globose, revolving green organism, somewhat resembling a small
volvox, which is found in equal profusion in ponds,
and even in such profusion sometimes as to impart a
green appearance to the water. This is the Pandorina. 1 There are two forms, one of which consists of
sixteen, and the other of thirty-two green cells, termed
gonidia^ closely associated together within a gelatinous
envelope of an oval form. Each
t,
green cell has a pair of cilia, or
movable hairs, which protrude
through the gelatinous envelope.
They usually are not more than
half the diameter of a volvox, and
present a different appearance, so
that there is no fear of any mistake in confounding the one with
the other. Ultimately some of the
green gonidia change colour, becoming brownish, acquire a thicker
coat, and pass into resting spores,
in which condition they remain a
PANDORINA.
while, and then develop into a
new generation, each resting spore
originating a colony of either sixteen or thirty-two
green gonidia, which constitutes the composite little
plant called a Pandorina.
Nothing is so useful for a beginner in the study of
these and similar objects as to be able to consult
and examine the plants themselves. For such purPandorina morutn.

FRESH-WATER ALG.E.

65

poses there have recently been prepared and issued
certain small collections of mounted specimens of
fresh-water Algse and other plants ready for examination under the microscope. 1 Such preparations are
far superior to any woodcuts or more elaborate illustrations, and will be found exceedingly valuable in
order to familiarize the young student with the various
types of structure which prevail in the different groups
of his subject.
There still remain to us a large number of decidedly
vegetable organisms, but of a very
simple structure;
profuse in all stagnant waters, and
consisting of a
single cell, or of
a few cells associated together, or
the simplest arrangement of simple cells. By far
the most complex
of these low forms
of fresh-water Algse
is the " Waternet/' 2 in which the
WATER NET.
cells are combined
into a net-work sac from an inch or two to six inches
1
Information may be obtained on application to W. Joshua,
Esq., F.L.S., Cirencester.
2
Hydrodictyon utriculatum.

F

66

PONDS AND DITCHES.

in length, and even more, but a complete skeletonbag of the most fairy-like character. Dr. Wood says*
that in the United States they frequently form floating
masses several inches in thickness and many feet in
extent, so that with the aid of a rake it could b e
collected by the bushel. 1 In this country, however,
they are local, if not rare. But the more simple
forms of what is termed the Protococcus group are
abundant, and many of them but imperfect conditions, or disintegrated forms of the more highlydeveloped Algae.
" They are composed for the most part of only one
cell of varying forms and colour, and are capable of
growing, of dividing, or segmenting into many parts,
and that in many directions, both round a common
centre, through their long axis, or through their short
one. The contents of the cell are also capable of
resolving themselves by subdivision into numerous
parts, not in any specific direction as above, by which
there is formed a group of small cells within the
parent cell-wall. Sometimes the parts separate from
each other at once, sometimes they remain in contact
for a variable period, whereby masses of cells are
formed more or less connected, but without any definite arrangement or mutual dependence; so that
any portion being separated is capable of continuing
its growth without suffering injury. The size of the
individual cells varies considerably, so that it seems
impossible to limit the extent to which they may
decrease by repeated segmentation. It may be carried
1

Grevillea, vol. ii. p. 54.

FRESH-WATER ALGiE.

67

to fine points, even seen under high microscopic
powers, in which condition they have been called
granules or molecules. These small fragments may,
however, grow till they attain the size of their
origin." 1
Not only do they vary in dimensions, but also in
colour, according to season and external conditions.
In winter they become more or less red or brown, but
with returning spring they resume a green tint. In
fact, the varied features under which they present
themselves are so puzzling, that Dr. Hicks was led
to protest against any faith in such organisms as autonomous species, until their life-history is ascertained.
It has been the want of giving due importance to
these considerations; the insisting with too implicit
faith on the identity or difference of green cells; the
attempting to give names and places to organisms
of which nothing is known but a simple cell, that
has led to the propagation of a theory with regard to
lichens, called the " dual lichen hypothesis," which
has obtained some adherents, and pertinacious defenders, making spasmodic efforts in opposition to
reason and fact.
The proper study and investigation of these little
fresh-water plants is quite sufficient to absorb all the
leisure of any one individual, and the result of such
concentrated observation would bring a much more
satisfactory reward than any amount of mere desultory observation. We suspect that anyone who
follows this course would readily endorse the obser1

Hicks, in " Popular Science Review," vol. iv. p. 335.
F 2

6S

PONDS AND DITCHES.

vations of our naturalist, Ray, with which this chapter
concludes.
" God is said to be maximus in minimis.
We
men esteem it a more difficult matter, and of greater
art and curiosity, to frame a small watch than a large
clock. And no man blames him who spent his
whole time in the consideration of the nature and
works of a bee, or thinks his subject was too narrow.
Let us not then esteem anything contemptible, or
inconsiderable, or below our notice-taking ; for this is
to derogate from the wisdom and art of the Creator,
and to confess ourselves unworthy of those endowments of knowledge and understanding which H e
hath bestowed on us. Do we praise Daedalus, and
Archytas, and Hero, and Callicrates, and Albertus
Magnus, and many others which I might mention,
for their cunning in inventing, and dexterity in framing and composing a few dead engines or movements, and shall we not admire and magnify the
great Former of the world, who hath made so many,
yea, I may say, innumerable, rare pieces, and these
too not dead ones, such as cease presently to move
so soon as the spring is down; but all living, and
themselves performing their own motions, and these
so intricate and various, and requiring such a multitude of parts, and subordinate machines, that it is
incomprehensible what art, and skill, and industry,
must be employed in the framing of one of them ?"

PONDS AND DITCHES.

69

CHAPTER V.
DESMIDS.

NAMES are meaningless sounds until we are able to
associate them with the objects which they represent.
This is especially the case with Desmids, since there
is nothing whatever in the name itself which could
help a solution of the mystery as to what they are.
This word is indeed a mutilated one, since it is a
contraction, employed for convenience, of the longer
and more pedantic word Desmidiacece^ which is a
scientific term representing a family, or order, of
minute Algae. These little plants are amongst the
simplest, although not themselves the simplest, in
the vegetable kingdom, since they consist of a single
cell, variable in form, chiefly with green contents,
and confined to fresh water. As they are uni-cellular
Algae, or Algae consisting of a single cell, they are
consequently very minute, so that their form is hardly
.to be distinguished by the naked eye.
Before we commence a description of the most
common forms, it will be necessary to give some
account of their habits and the places where they are
to be found.1 They are gregarious, being found in
1
As this can only be done briefly and partially, the reader is
referred for further assistance to a useful little volume called
" T h e Collector's Handy Book," by J. Nave, published by
D. Bogue.

70

PONDS AND DITCHES.

such numbers as to give a green tint to the water or
mud, when most prolific; and even when the colour
is not apparent, numbers will be found together, in
bogs, ditches, ponds, which are exposed in bleak
situations, and not enclosed in woods, especially in
little pools where the bog-moss (Sphagnum) abounds,
on heaths and damp moors. They love to flourish
in holes and pools, where the water is clear and pure,
and the soil of a clayey nature, where they sometimes
cover the bottom with a green film. Often numbers
of them will be found adhering to the stems of
sphagnum, from which they float when immersed
and stirred about in clear water. The surface of wet
rocks will afford some species, when the pure water
percolates and drips; hence some of the most interesting and varied collections have been made in
mountainous districts, such as North Wales. The
autumn is the best season for collecting them, but
they will be found throughout the summer. When
found coating the bottom of a pool with a green
stratum, they may be taken up with a spoon and
placed in a wide-mouthed bottle. After being shaken
gently so as to separate the mass, the bottle placed
in the light, the sediment will sink to the bottom and
the Desmids will gradually rise to the light, and then
they may be separated by decanting. If poured into
a white soup-plate the floating Desmids may be taken
out on the tip of a camel-hair pencil with the aid of
a pocket lens, and thus the largest specimens may be
isolated. A little experience will soon prove the best
guide to their manipulation. In order to see them,
as we shall describe them, a microscope with an inch

DESMIDS.

71

objective will be necessary, and even a higher power
to make out the details.
All the Desmids consist of a transparent envelope
or cell wall, enclosing a green colouring matter which is termed the endochrome. The differences in the
form of this envelope and the disposition of the endochrome are the
basis of the genera and species into
which the Desmids are divided.
Unfortunately, they have never been
sufficiently known to acquire popular
names, and hence our only alternative will be the employment of those
adopted for scientific purposes.
One of the largest and most common forms is Closterium; it is of
little consequence which particular
species, out of a great many, as the
general form and character is the
same. They are elongated, gradually
narrowed towards each end, slightly
curved like a new moon, or nearly
straight, with a band or mark in the
centre, and a clear space at each
-end. The central band indicates the
point at which the cell ultimately
divides, so that the endochrome
escapes, and empty cells will sometimes be found in company with CLOSTERIUM.
those containing the green endochrome. There are often darker longitudinal bands

72

PONDS AND DITCHES.

in the endochrome and scattered paler spots or
vesicles, which latter are sometimes symmetrically
arranged. By careful observation a distinct circulation may be traced going on up and down near the
margin of the cell in its living state. The various
species of Closteriuvi are from one-fortieth to 150th
of an inch in length, and one-eighth to one-sixth of
those dimensions in breadth. The largest only are
visible to the naked eye.
The mode of reproduction is of two kinds, one by
a gradual separation at the central band, when each
half continues to grow and forms a separate and
complete individual. This is the process of selfdivision. The other is when two individuals come
in contact at the centre, and a globose body is
formed between them, called a sporangium, or more
correctly, zygospore, which in due time produces a
great number of spores, and these develope into
Closteria, individuals like the parent from which they
sprung. This is the process of conjugation.
It has been stated, not uncommonly, in works on
the microscope, that another mode of reproduction
is found in Desmids, by means of zoospores. 1 It
must be admitted, as not at all beyond the bounds
of probability, that this mode of reproduction may be
found to prevail to a limited extent. It is known
that in other fresh-water Algae these curious little
bodies are developed, but hitherto, as far as we are
aware, the evidence is very slight, and depends
entirely upon the single instance, recorded by
1

See fig. on page 52.

DESMIDS.
1

73

Mr. Archer of Dublin. After examining all the
affirmations on this subject, and tracing them to their
source, this gentleman came to the conclusion that
no evidence could be found of the occurrence of
zoospores in any Desmid up to the period of his
communication. Afterwards he proceeds to a description of a peculiar condition of a Desmidian, called
Doa'dium, which he met with, and in which bodies
strongly resembling zoospores were seen. Hitherto
these observations have not been confirmed, although,
personally, we do not feel the least doubt of their
accuracy.
First of all, the regular process of conjugation
takes place thus.
The conjugative act is not
undertaken till after the two original fronds, about to
conjugate, have undergone self-division in the usual
manner, that is to say, by self-fission, effected by a
division of the contents into two, just under the
suture, accompanied by a development of a new cellwall to each old segment; and separation taking
place, the separated portions have now one long (and
old) cone, and one more blunt and rounded (the
nascent younger one). Now, in those individuals
about to conjugate, from each of the shorter or
younger cones is protruded a blunt, pouch-like
projection from the lower and opposed sides of
each, which, approaching gradually, the contents
amalgamate with each other; at the same time, the
other opposite portions of the original parent fronds
acting in precisely the same manner. Thus two
1

"Micro. Jour.," viii. (i860), p. 215.

74

PONDS AND DITCHES.

sporangia (or zygospores) ultimately result from
the two original fronds, conjugation taking place
between each of the opposite individualized pairs
of partially old, partially new, fronds, themselves
resulting from the self-division of the original parent
fronds.1
And now as to the bodies in question. The first
indication of the commencement of the phenomenon
is the production of a minute hyaline tubercle, just
under the inflation at the base of the younger segment This tubercle arises from a special extension
of the boundary-wall interposed between the inflated
base of the segment and the suture. It is, in effect,
an addition to the base of one of the segments. This
basal tubercle gradually elongates, and becomes a
tube in direct connection and continuation of the
frond, like the finger to a glove, and as of variable a
length. Some cease to grow after reaching one-tenth
or one-eighth of the length of the frond, whilst a few
will grow nearly as long as the frond itself. The
endochrome near the base of each segment becomes
finely granular, of an almost homogeneous appearance,
and the new tube is filled by it. The remainder of
the endochrome is but little altered. The endochrome
which had become granular, and filled the lateral
tube, in the next change becomes segmented into a
definite number of rounded portions, perhaps not
less than twenty, or more than fifty. These spherical
bodies formed by segmentation of the granular endo1
See "Annals of Natural History,''vol. v. (second series),
p. i, for further details.

DESMIDS.

75

chrome, in the next stage emerge from the open apex
of the lateral tube, and remain clustered together in
a mass, resembling a bunch of grapes; the clusters
becoming larger and larger, until all the spherical
bodies have emerged. Each of these appear to form
for itself a special cell-wall of a slightly compressed
or elliptical form, within which the green contents
are seen to be somewhat retracted. Subsequently, a
movement in the contents of each of these newlyformed cells is visible, which takes the appearance of
a twisting motion, backwards and forwards, as it
were, on its axis. This'movement is not apparent in
all the members of the group simultaneously, but
only in a few at a time. Eventually the green bodies
escape, and swim away as ovate or pear-shaped
ciliated bodies, pale at the narrow or pointed end, in
every way comparable to the mobile zoospores found
in other Algae. Whether one or two cilia were present
cannot be determined. The old frond having perperformed its work separates at the suture, and finally
decays. Throughout this process, and in its final
development, there is every reason to regard the
phenomenon as a development of zoospores, differing
in no very essential particular from those which are
developed in Chcetofihora, and indeed in many other
Algae.
Another form equally common with Ciosterium is
Euastrum. The cell, or frond, is flattened, lozengeshaped or oblong, with a deep fissure on each side
at the centre, so that the cell is nearly divided into
two equal halves, the margin of each segment deeply
waved or divided into lobes. The surface of the

76

PONDS AND DITCHES.

cell-wall, or envelope, is sprinkled with little elevated
warts or prominences. The same modes of repro-

EUASTRUM {oblongicm.)

EUASTRUM (didelta).

does not exceed 150th of an inch, and many are not
one-half that size.
In Micrasterias, the cell or
frond is shorter, and more
rounded than in Euastrum.
It is divided on each side
nearly to the middle into two
equal segments, in a like manner, but each segment is more
nearly semicircular. The margin is more deeply cleft into
MICRASTERIAS.
narrow lobes, which are often

DESMIDS.

77

toothed at the extremity. The individuals are usually
larger than Euastrum, and often of very beautiful stellate forms.
In Cosmarium we have smaller
forms, but some of the species are
very common. The general outline is oval, deeply cut nearly to
the centre into two equal segments,
which are broader than long. There
are no divisions or notches at the
margin, and the frond (name applied to the whole plant) is more
inflated than in the other forms.
The surface of the cell-wall is often
warted, as may best be seen in the
COSMARIUM.
empty fronds.
We have now enumerated the
common forms, of which some
species is sure to be met with in
favourable localities, but there still
remain a few of the rarer Desmids,
of which occasional examples may
be seen intermixed with the commoner. One of these forms is that
called Penium, which is elongated,
nearly cylindrical, rounded at the
ends, quite straight, in all of which
it differs from Closterium, with
which, perhaps, the novice is most
likely to confound it.
In one
British species the fronds are, at
the least, one-eightieth of an inch
PENIUM.

78

PONDS AND DITCHES.

long; in Wales it is said to be very common, and has
been collected in the neighbourhood of London.
In Docidium the fronds are still more elongated,
cylindrical, quite straight, and differing from Penium
in being constricted at the centre.
^
Spzrotcenia, again, is similar in
its cylindrical form, but with two
/
\
important and distinctive fea/
tures,—viz., that the frond is sur\
rounded by a clear gelatinous
envelope, and the endochrome
I exhibits a spiral band. It is
often difficult to see the gelatinous envelope, as it is so very
transparent. We have found that
a solution of any one of the aniline dyes is very useful in defining
such structure under the microscope. If a small drop is placed
at the end of the covering glass
it will run in, tinge the water,
leaving the margin of the hyaline
envelope clearly and sharply defined. This little device is so
simple and so invaluable that we
marvel at its being so little known,
or, at any rate, so little adopted.
To other forms of free swimming Desmidsweneed not allude,
SPIROT^NIA.
except to say that there are other
rarer forms which must be studied in some work
specially devoted to the group.

DESMIDS.

79

There are, however, two or three forms of Desmids in which the individual cells, or fronds, are
gregarious, attached together in
filaments, and surrounded by a
gelatinous envelope which retains
them in that position. Whether
we call them Hyalotheca, or
Sphczrozosma, or Didymoprium,
there is a great similarity between
them, so much so that an unpractised eye would not detect
the differences, which, after all,
concern only the specialist. Take
Hyalotheca, for example, and it
consists of long fragile filaments,
something like a conferva, very
gelatinous, enclosing, or surrounding the joints, each of
which is a separate individual,
and in time the filaments will
HYAL6THECA.
break up into the individual
joints, each surrounded by a mucous envelope. The
end view of each joint is circular, but the side view
is quadrangular, broader than long, with a groove
running round the centre of each cell or joint.
In other instances the end view is triangular, or
quadrangular, but in Hyalotheca the filaments are
cylindrical, so that the section is circular. Sporangia
(or zygospores) are formed just as in other species.
Only one book has been written in this country
devoted specially to the Desmids, and that has now
become very rare. In the introduction its author

8o

PONDS AND DITCHES.

(J. Ralfs) gives the following hints about collecting
— " In the water," he says, " the filamentous species
resemble the zygnemata, but their green colour is
generally paler and more opaque. They often occur
in considerable quantity, and, notwithstanding their
fragility, can generally be removed by the hand in
the usual manner. When they are much diffused in
the water, I take a piece of linen, about the size of a
pocket-handkerchief, lay it on the ground in the form
of a bag, and then, by the aid of a tin box, scoop up
the water and strain it through the bag, repeating the
process as often as may be required. The larger
species of Euastrum, Micrasterias, Closterium, & c ,
are generally situated at the bottom of the pool,
either spread out as a thin gelatinous stratum, or
collected into finger-like tufts. If the finger be
gently passed beneath them they will rise to the
surface in little masses, and with care may be
removed and strained through the linen as above
described. At first nothing appears on the linen
except a mere stain or a little dirt; but by repeated
fillings up and straining a considerable quantity will
be obtained. If not very gelatinous the water
passes freely through the linen, from which the
specimens can be scraped with a knife and transferred to a smaller piece) but in many species the
fluid at length does not admit of being strained
off without the employment of such force as would
cause the fronds also to pass through, and in
this case it should be poured into bottles until
they are quite full. But many species of staurastrum, pediastrum, & c , usually form a greenish or

DESMIDS.

81

dirty cloud upon the stems and leaves of the filiform
aquatic plants, and to collect them requires more
care than is necessary in the former instances. In
this state the slightest touch will break up the whole
mass and disperse it through the water. I would
recommend the following method as the best adapted
for securing them. Let the hand be passed very
gently into the water, and beneath the cloud, the
palm upwards, and the fingers apart, so that the
leaves or stem of the invested plant may lie between
them, and as near the palm as possible; then close
the fingers, and keeping the hand in the same position, but concave, draw it cautiously towards the
surface, when, if the plant has been allowed to slip
easily, and with an equable movement through the
fingers, the Desmids in this way brushed off will be
found lying in the palm. The greatest difficulty is
in withdrawing the hand from the water, and probably but little will be retained at first; practice, however, will soon render the operation easy and successful. The contents of the hand should be transferred at once either to a bottle, or, in case much
water has been taken up, into the box, and when this
is full it can be emptied into the linen as before.
But in this case the linen should be pressed gently,
and a portion only of the water expelled, the remainder being poured into the bottle, and the process repeated as often as necessary."1
Thus much with respect to collecting, but we
cannot close the chapter with more appropriate ob1

Ralfs' "British Desmidiaceae," p. 38.
G

82

PONDS AND DITCHES.

servations than those with which the author just
quoted concludes his "Introduction":—"What the
All wise did not disdain to create cannot be unworthy
of notice; and if, in the minute Desmidiaceae, so long
concealed from the unassisted eye, we have been
at length enabled to recognize objects as carefully
organized as the bulky elephant or the majestic oak,
and as happily adapted to their position in nature,
possessing too an economy whose laws are no less
constant and regular, shall we not gladly examine this
fresh evidence of an Almighty hand, as distinctly
impressed on them as on the rest of His creation ?
" T o Him no high, no low, no great, no small;
He fills, He bounds, connects, and equals all."

PONDS AND DITCHES.

CHAPTER

S3

VI.

DIATOMS.

WHAT are Diatoms? Microscopical aquatic plants,
even as Desmids are, and like them consisting of a
single cell, so that both are equally included under
the name of Unicellular Algae. This, however,
is quite insufficient for an explanation of what the
Diatoms are, for they have a singular history. At
one time it was firmly believed that they were little
animals ; it is now as firmly declared that they must
be plants. In writing of Desmids we intimated that,
when living, their colour was a beautiful green; on
the other hand, the Diatoms, when living, are as uniformly pale»golden brown. There is, however, a still
more characteristic feature in these minute plants,
which is, that their skeleton is an indestructible pair
of transparent plates, of the same substance as glass,
that is to say, of silex, or flint—two thin plates of
flint applied to each other by their surfaces, and
united by a marginal band. This is the type of
structure in the Diatom skeleton. The endochrome
or vital portion is coloured, but when the plant is
dead, and the endochrome dissolved, the skeleton
still remains, indestructible as flint. Century after
century these delicate skeletons remain, until they
accumulate and form immense beds, consisting of
G 2

&4

PONDS AND DITCHES.

the skeletons of myriads of Diatoms. It is a fact,,
often alluded to, that the city of Richmond, in Virginia, is built on a stratum of diatomaceous remains,
sometimes eighteen feet in thickness. There are
also other large tracts of fossilized Diatomacese in the
United States and other parts of the world. Formerly these plants flourished in some sea, lake, or
other expanse of water. They died, and the skeletons being heavier than water fell to the bottom,
forming a thin layer over the mud. Year after year,
and century after century, the little plants continued
to 'multiply and to die, and contribute their skeletons
to the stratum at the bottom, until at length, when the
lake dried up, or its waters were diverted, the skeletons
still remained, as an incontrovertible evidence of the
existence of themselves, and the lake in which they
flourished ages ago. Some of these deposits consist
entirely of the skeletons of Diatoms. We have seen
them so purely diatomaceous that the microscope
could detect nothing else but these skeletons, or
frustules, compacted into a friable mass. In Jutland
the deposit is converted into a hard stone, containing
some of the most beautiful of known forms.
It would be a mistake to suppose that because
there is uniformity in the structure of these microscopical organisms, there would also be a great similarity
of form. On the contrary, the form is exceedingly
variable : some are circular or discoid, to a mathematical accuracy; others are triangular, quadrangular,
polygonal,boat-shaped, oval, elliptical, fusiform, linear;
in fact, the forms are numerous and diverse, but
usually symmetrical. To increase their beauty, and

DIATOMS.

85

our wonder, the surface is covered with the most
delicate tracery of lines, dots, ribs, channels, spines,
forming exquisite patterns, which require very high
powers of the microscope to reveal in all their delicacy. And yet very few of these minute plates or
frustules are visible to the naked eye. More beautiful geometrical patterns can scarcely be conceived
than those of some of the discoid Diafcomaceae. No
stronger evidence need be sought of the infinite
power and wisdom of the great Creator of all.
The indestructibility of these skeletons serves to
indicate the universality of these little plants. They
are to be found almost everywhere. We take a
tuft of bog-moss, and rinse it well in a vessel of clean
water, then, with a dipping-tube, draw up a drop
from the bottom of the vessel, place it under the
microscope, and behold five or six different kinds of
Diatoms. Desiccate an oyster, destroy all its animal
substance, and still there remain skeletons of Diatoms. The guano, which is brought over to this
country for manure, contains large numbers of them,,
devoured by sea-birds, deposited in their excrements,
and exported as guano. In fact, they flourish in salt
water, or fresh water, but especially in the former,
everywhere; are devoured in tuorns by aquatic animals of all kinds, and hence find their way into the
most unsuspected places, so that they are almost
ubiquitous.
" I suppose," says Nave, "that there is scarcely
a single piece of water anywhere which does not
contain at least some individuals of the commoner
species. They are to be found alike in the lake

86

PONDS AND DITCHES.

that crowns the mountain top, and the swamps and
peat-beds which fill the lowest valley; in the watercourse employed to irrigate the meadows'; in the
broad ocean, and the shallow puddle left by the
overflowing of a ditch; the brackish water, where
the tidal river meets the sea; salt-works and salt-pits ;.
even inland lakes, which have a trace of salt in them,—
each affords a rich variety of characteristic Diatomaceae, varying according to the chemical quality of
the water. They are to be frequently found also on
rocks and masses of stone, damp from overhanging
trees, or from the constant trickling of water."1
Many of these localities are not within our jurisdiction, but Diatoms are plentiful enough in poolsr
ponds, and ditches. The most beautiful and largest
forms are marine, but the fresh-water species are by
no means few or insignificant. We have already
indicated the readiness with which they flourish
amongst the bog-mosses (Sphagnum) in swampy
places. The earliest and surest effort of the young
collector should be directed to this source, by means
of which he will make a first acquaintance with the
Diatomaceae.
We are indebted to the generous aid of a friend,2
who has devoted himself specially to the study of
these minute organisms, for the residue of this chapter. On such a subject his words would possess
more authority than our own, and we willingly acknowledge his ready assistance.
1
2

Nave's " Collector's Handy Book."
F. Kitton, Hon. F.R.M.S.

DIATOMS.

87

The tyro in the study of pond life has no doubt
observed certain minute organisms differing in form
and colour from the surrounding objects, some of
which move about with considerable activity. The
colouring matter, unlike that of the majority of minute
vegetable forms, is usually of a golden-brown colour.
These organisms are now generally known as Diatomaceae or Diatoms. The first discovered representative of this order was the so-called "Oat animalcule f
the discoverer was a Mr. William Arderon, F.R.S.,
who found it in a ditch in Norwich, in 1745; it was
afterwards described in Baker's " Employment for
the Microscope." This form was some species of the
genus Navicula. These organisms were called by
early observers Bacillaria, or " Staff animalcules," a
term still retained by some of the German observers.
Agardh introduced the name Diatomae, deriving it
from the genus Diatoma (diatom'e, incision), a filamentous form, of which the cells composing the filament cohere at their alternate angles, having the appearance of a band nearly cut through in opposite
directions. Both names are open to objection, as
they only indicate the characters of a few genera.
The position of the Diatomaceae has long puzzled
the student: some microscopists contended for their
animal and others for their vegetable nature (the
great Ehrenberg always maintained the former opinion,
and placed them with the Desmidiae and some forms
of true animalculae in his family Polygastrica—manystomached) ; others were equally positive that their
true place was in the vegetable kingdom; others again
considered them to be plant animals (Phytozoa);

ss

PONDS AND DITCHES.

some few even placed them in the mineral kingdom.
The now generally received opinion is that the
Diatomaceae are true unicellular Algae, differing
however in many important points from any other
forms in that group. The principal are, first, the
nature of the cell-wall, which is composed of silex or
flint,1 secreted by a thin membrane; second, their
mode of increase by a self-division f third, the
peculiar nature of the cell contents, which contain a
colouring matter not found in other Algae, and which
is called Diatomine. The diatom cell is usually described as resembling a pill-box. This is a tolerably
good description so far as the circular forms are concerned, but the comparison is somewhat obscure to
the " staff-shaped " species. We will now endeavour
to describe, in as plain and brief a manner as possible,
the structure of the Diatom cell.
The structure is most easily discerned in the circular form. In its earliest condition the cell has the
appearance of a double convex lens, but as growth
proceeds the convex surfaces recede, and a band is
formed by the sides of the pill-box, which gradually
increases in breadth. If we take two pill-boxes (minus
the lids), which we will call a and b, the latter small
enough to slide into the former, we have a fairly
correct idea of the Diatom cell.
When this cell has attained its maximum develop1
The flinty nature of the Diatom cell was first demonstrated
by Kiitz in 1834.
2
Increase by self-division is not peculiar to the Diatomaceae,
but the manner in which this takes place differs from that in
any other form of Algae.

DIATOMS.

89

ment the cell contents begin to divide, one portion
receding to one end of the cell and the second to the
other, and in a short time a new end is formed to a
and we have a cell in all respects like the first. The
same occurs with b. We have now two perfect cells,
one of which is smaller than the other by the thickness of the band; in the free forms the cells usually
separate, but in many genera the cells continue
attached, thus forming a filament or chain. This
process goes on until the productive energy is destroyed, but the number produced by the parent cell
is probably .very large. We have many times carefully measured the thickness of this band, and never
found it exceed the T o w o 0 I * a n m c n m thickness.
The shape of the Diatom cell is very variable; they
occur circular, oval, triangular, square, 5, 6, 7, 8, and
10 sided, boat-shaped, wand-like, sometimes curved
in opposite directions, sometimes only in one. But
the structure is always the same, viz., the two lids and
the band connecting them. The former are usually
termed valves, and the latter the connecting zone or
cingulum. It is from the form of, and the markings
on, the valves that the generic and specific distinctions
are principally constituted. 1 These markings are
generally of great beauty, and usually require the
highest microscopic powers to show all their details,
particularly those forms on which the markings appear
as fine lines, the so-called test objects. One species
1
Some foreign diatomists have proposed to classify these
organisms according to the arrangement of the cell contents,
but as this can only be studied during the life of the Diatom, it
has not met with general acceptance.

90

PONDS AND DITCHES.

(Amphipleura pellucida) in particular has lines so
close that as many as 94 in the ytroo" °f a n m c n n a v e
been counted, and by certain arrangements of the
light these lines are found not to be continuous but
composed of minute dots. The nature of these
markings has always been a disputed question, some
asserting that they are elevations on the surface, whilst
others have been equally positive that they are minute
cells in the siliceous wall. That the latter theory is
true in some species has, we think, been clearly
demonstrated in some of the large marine forms, but
it is not so evident in the more delicate species.
Some genera are usually found attached to the larger
Algse by non-siliceous stalks, whilst others are enclosed in membraneous tubes generally of a green
colour and sometimes several inches in length; they
then have the appearance of delicate filamentous
Algse.
The movements of the Diatoms excited the wonder
and curiosity of the earliest observers, and was a great
argument in favour of their animal nature. The means
by which these movements are produced has not yet
been explained. By some it was supposed to be
caused by the extension and, retraction of a foot or
feet,, and by others the expulsion of water from the
ends of the cell. It is only among the elongated, or
staff-shaped forms, that these movements are conspicuous, but that all non-parasitic forms possess the
power of locomotion can be proved by placing a
gathering containing them in the sunshine, when they
will be found in a short time on the surface mud,
appearing like a film of a golden-brown colour.

DIATOMS.

9r

These organisms occur in fossil deposits in all parts
of the world, sometimes forming beds of considerable
extent and great thickness. We received a few years
ago a specimen of deposit occurring in Australia,
evidently the bottom of an ancient lake many acres in
extent. This deposit was stated to be twelve feet in
thickness, and consisted almost entirely of the remains
of a small Synedra (the largest did not exceed y ^ of
an inch in length and T ^ ¥ in breadth). The mind is
incapable of conceiving the enormous number of individuals composing this deposit.
As it is not our intention in this work to give any
minute scientific classification or specific description
of the objects to be found in our ponds and ditches,
we shall only describe those diatoms which are most
likely to be met with in such places.
The prevailing forms in fresh-water are bacillar, or
staff-like, of which the Navicula (little ships) group
afford the largest number. This group is distinguished (with one or two exceptions) by the valve
being divided longitudinally by a line, in the centre of
which is a central spot (nodule) more or less conspicuous, and terminating with two smaller spots. The
following are a few of the forms which are most likely
to be found in ponds and ditches :—
Of the boat-shaped forms belonging to the genus
Navicula, the Spotted Navicula1 first deserves noticeIt is of an oval form, with blunt, beak-like ends.
When dry it has a very distinct circular spot in the
centre of the valve, and two smaller ones at each end.
1

Navicula sphcerophora.

92

PONDS AND DITCHES.

Another, very much resembling this in shape, is called
" Amphisbaena."1 If we consult the lexicon we find
that the original amphisbaena was a snake having a
head at both ends, so that it was capable of moving
both ways. The amphisbaena diatom does not taper
so gradually towards the ends as in the preceding
species, and the beaks are broader. When dry, a
broad marginal band of a pale brown colour surrounds the valve, leaving an oval transparent space
in the centre. This band, when properly illuminated
under the microscope, will be found to be composed
of fine parallel lines.
As these minute objects have no popular names of
their own, it would scarce serve any good
purpose to invent them, and it is better to
adopt the practice which prevails with the
majority of microscopists of calling them
by their trivial names. Thus, the next
species is " serians,"2 and this may be
remembered as readily as a more commonplace name. This species is narrower than
. the last, and the margins gradually taper
towards the ends, which are abruptly
pointed. When dry, the central spot is
;# very conspicuous, and rows of longitudinal
lines are visible on the valve.
A much larger form than any of the preceding is
•"cuspidata."3 The valve has a somewhat angular
1
3

Navicula amphisbana,
Navicida cuspid ata.

2

Navicida serians,

DIATOMS.

93

outline, with the ends slightly rounded. In the dry
state it is transparent, with a very slight pink tinge and
has distinct transverse lines reaching to the centre.
The next is " rhomboides ' a and has a reputation
beyond the ranks of the diatom-hunters,
for reasons which will presently appear.
It very much resembles the former species,
but is not more than half its size. It is
perfectly transparent when dry, and the
markings on the valve are only visible
when examined by glasses of the most
perfect construction. The resolution of
these lines is usually considered an excellent test of the accuracy of the optician's
work, so that " rhomboides " enjoys the
reputation of being one of the so-called RHOMBOIDES.
" test-objects," by which the quality of
microscope lenses is tested.
Although there are many other species of this genus
we will now pass to another, called Pinnularia, which
has a close relationship with Navicula, but is distinguished by the coarseness of the transverse markings,
and the fact that they cannot be resolved into dots,
as is the case with the finer lines on the true species
of Navicula. The first species is called " viridis " 2
and is one of the most common of fresh-water diatoms.
It has an elliptical outline, with rounded ends; the
markings nearly extend to the line which passes down
the centre, and in the centre of this a nodule is very
Navicula rhomboides.

2

Pinnularia viridis.

94

PONDS AND DITCHES.

distinctly apparent. A friend suggests that it has
been called viridis because it is never "green."
Another species, of which we have
given a figure, is called "major." 1
It
has nearly straight sides, with broadlyrounded ends, the markings, or ribs, are
conspicuous, and the central nodule
large.
A still larger form is that called
"gigas," 2 which resembles the preceding, but the costse, or ribs, are more
distinct. It is most frequently found
in boggy pools in elevated districts.
There is a much smaller species called
" l a t a " 3 which is easily identified by its
distant and conspicuous ribs, which become shorter as they approach the central
nodule. It is only found in sub-alpine
localities. Another, called " A l p i n a " 4 is
frequently found associated with it. This
is larger, and has a more elliptical outline
PINNULARIA than "lata," which, however, it resembles
MAJOR.
- n «ts c o n S p i c u o u s a n ( j distant ribs.
There is another group, or genus, to which the
name of Stauroneis is given, and its difference from
the preceding may be easily recognised by comparison
of the figures. The outline is that of Navicula, but
from this they are distinguished by a smooth central
band crossing the middle of the valve. The one
Pinnularia major.
Pinnularia lata.

2
4

Pinnularia gigas.
Pinnularia alpina.

DIATOMS.

95

1

called "phaenicenteron" of which we have given a
figure, has the outline of that Navicula which is
termed " cuspidata," but from this
it can readily be distinguished, when
dry, by the central band, and its
darker colour.
The peculiar movement, of which
we have already spoken, is perhaps
nowhere better seen than in a group
of diatoms called Pleurosigma.
They are easily recognised by their
sigmoid outline, the central, or median line usually having the same
curvature as the margins. T h e
larger proportion of species are only
found in salt or brackish water, the
one called " attenuatum," 2 however,
is common in fresh water. When
dry it is of a purplish colour, and

STAURONEIS

the surface is covered with dots PH^NICENTERON.
arranged in straight lines.
Whilst examining specimens of the delicate filamentous Algae usually known by the name of Confervae,
the observer is almost certain to detect little needlelike tufts attached to them. These are sometimes so
numerous as to give a spiny appearance to the
filament. These are diatoms belonging to the genus
Synedra, which contains a great number of species,
many of which are common in fresh water. There
are two kinds which are almost certain tb be found.
1

Stauroneis phcenicenteron.

2

Pleurosigma attenuatum.

96

PONDS AND DITCHES.

That called " capitata" l is long and narrow, with
straight sides, the ends suddenly expanded into a
wedge-shape; in the centre is a small round space,
the remainder of the valve being covered with straight
lines of dots. The other species, " r a d i a n s " 2 differs
from the preceding by the margins gradually tapering
towards the ends, which are rounded. When living
it grows attached in star-like tufts. It may be added
that these are minute species as compared with the
majority of those immediately preceding.
Amongst the disc-shaped forms found in ponds
and ditches are species of the genus Campylodiscus ;.
a long name, it is true, but the objects are wrell worthy
of an aristocratic name. This genus is easily recognised by the valves being saddle-shaped, or bent in
opposite directions. The one most commonly met
with has the centre of the valve smooth, 3 or finely
dotted, surrounded by a broad margin of distant stout
lines.
Somewhat related to the foregoing is the genuscalled Surirella, and, indeed, some of the species bear
considerable resemblance to Campylodiscus.
Amongst fresh-water species the following may be
indicated. The one is " biseriata," 4 having a narrow
oval shape, with pointed ends. The centre of the
valve has a narrow, smooth line, running from end to
end, and separating the conspicuous transverse bands
or folds. The other is " nobilis," 5 less common than
the preceding, but nevertheless frequent in subalpine
1
3
5

Synedra capitata.
CamJ>y/odiscus costatus.
Surirella nobilis.

2

Synedra radians.
4
Surirella biseriata.

DIATOMS.

97

pools. The valve is egg-shaped, the folds distant,
reaching the median space.
We have passed rather rapidly over these dry
details of some of the more common forms, more for
the purpose of indicating the variety to be met with,
and to serve as types, rather than to furnish an exhaustive catalogue, which would have been drier stilL
Only a few remain, which demand a
passing observation. A genus of parasitic diatoms will often be found, in
some of its forms, infesting not only
the larger Algae but also other diatoms,
adhering like the common " scale insect," or coccus, from which its name of
Cocconeis is derived. The only freshwater species that we have in this
country are those called Pediculus, and
Placentula.
They differ slightly in
general appearance, the valves in both
COCCONEIS,
species are marked with fine longitudinal lines, and have a series of small dots surrounding the inner margin. The principal distinction
is that the former is more broadly oval than the
latter, and the ends less pointed.
One other type is Cocconema^ of which the species
we have in view J is of very frequent occurrence, and
is easily recognised by its bow-shaped outline and
beadlike markings. In this genus the median line is
no longer central, but is more or less close to the
inner or concave margin. The species are frequently
Caocmmna lanceolatum*
H

98

PONDS AND DITCHES.

attached at one end to a long stalk, by means of
which they adhere to other Algse.
In order to distinguish the generic
and specific characteristics of the
Diatomacese, it is generally necessary
to get rid of the cell contents, and
separate the valves. This may be
accomplished by boiling in nitric
acid, and afterwards washing in distilled water until all traces of acid
disappear. The details of this process will be found in any of the
excellent treatises on the use of the
microscope.
COCCONEMA.

PONDS AND DITCHES.

99

CHAPTER VII.
LOW-LIFE (PROTOZOA).

WE have reached the borderland between the
vegetable and animal kingdom, where the organisms
on both sides are reduced to a simple cell, where
our real knowledge is small and our presumption is
great. We know from experience that small bodies,
which consist of a single cell, can move about with as
much freedom and vivacity as animals, and yet these
bodies emanate from, and are capable of producing,
undoubted plants. The old notions of what constituted an animal, and what a plant, have now malted
into the air, and we are compelled to admit the
difficulty, if not impossibility, of defining in words
the limit between animal and plant, when each is reduced to its lowest terms.
The warm controversy which raged but a year or
two ago has subsided into a calm. This controversy
on atoms and spontaneous generation, and heterogeny,
or by whatever name it was called, doubtless commenced in France, and thence spread over Europe.
It was an old axiom, or a saying treated as an axiom,
that every living thing proceeded from an egg or germ
derived from a similar parent-. That not only did a
hen proceed from a hen's egg, but all other animals,
H 2

IOO

PONDS AND DITCHES.

and even plants, from a germ-cell, which was equivalent to an egg. It was supposed that given cells,
produced, for example, from a low form of Algae, or
water-weed, would in turn develope into a similar
water-weed. That in some cases there might be intermediate stages, a kind of alternation of generations,
but ultimately the child would resemble its parent.
This is something like panspermy. The panspermists held that from certain definite germs organized
beings originate in accordance with inflexible law;
that, for instance, toads are not hatched from hen's
eggs but from toad-spawn; whereas, on the contrary,
the heterogenists held that from certain germs, either
plants or animals may be developed, as circumstances
favour the one or the other; in effect, it was haphazard as to what the latent germ would produce.
It is confessedly difficult to determine when certain
little bodies are floating about on the field of the microscope whether they are animal or vegetable. They
behave themselves, for a time, just like animals, but if
their development be followed they may culminate in
vegetable organisms. The conclusion has been
guessed at, rather than demonstrated, that these
active little bodies may, according to the conditions
in which they are placed, eventually become either
plants or animals. Even if it be admitted that " the
very lowest forms of vegetable and animal life cannot
be traced back to spores or ova/' it by no means
follows that they could not originate from spores or
ova. The emphasis belongs to the word " traced."
We cannot admit that in the operations of Nature
there is any such uncertainty as to the destination of

LOW-LIFE (PROTOZOA).

IOT

the smallest atom as the heterogenists assumed.
Practically, however, the controversy is over. Admittedly it failed to demonstrate what it assumed, and
there is no longer any reason to show battle against it,
but it may reappear in another form. Meanwhile,
it behoves us to endeavour to comprehend, as far as
we can, the mysteries of life as exhibited in its lowest
forms.
" For He whose mercy is o'er all His works
Forgot not one of this large family,
But cared for each as for an only child."

There is a very simple animal with a low form of
organization, which has been called the Proteus from
its habit of constantly changing its form. In ditches,
water-butts, stagnant water of all kinds, this little
creature is to be found. A little microscopical
animal, so colourless and transparent as to be almost
invisible from the very gelatinous character of its
substance. It is, in fact, a little lump of jelly, vivified
jelly, moving jelly, but still a jelly, and scarcely anything more. It is just what naturalists call a piece of
protoplasm, and a most anomalous creature it seems
to be. Imagine a minute speck of isinglass jelly
endued with life, and you have an Amceba, a Proteus,
a Rhizopod without a shell. It has no mouth, no
eyes, no legs, no hands, no feet, no stomach; yet it
performs the functions of all these. No mouth, yet
it extemporizes a mouth from any portion of its surface, involves, and draws in its prey; no legs, yet it
elongates and pushes out any portion of its gelatinous
substance like a leg to move itself about. No
stomach, yet it takes food, and gathers it into the

102

PONDS AND DITCHES.

midst of its gelatinous mass, digests it, and rejects the
undigested portions. Now it is almost spherical,
then it becomes oblong, lengthens itself into a long
and narrow body, and then as speedily becomes
triangular, or star-shaped, or many-sided. In fact, it
is a very Proteus, every instant changing its form and
assuming every shape of which a plastic lump of
gelatine is capable.

PROTEUS, OR ANLEBA.

Put this creature inside a shell, in shape like a
bottle, a flask, or a snail-shell, and it becomes a Foraminifer, protruding its jelly-like substance through the
pores of the shell, like false feet, and thus moving itself
about. Or place it in a flinty skeleton of variable
shape, and it becomes a Polycystin. Or give it a
horny skeleton, strengthened with ribs of flint, and
collect myriads of individuals into a collective mass,
and we have a sponge. Sarcode, or protoplasm, or
-whatever else you may please to call this living jelly,
it is typically the same in all these creatures, which
are really animals in such a simple condition that,
instead of possessing special organs, endowed with

LOW-LIFE (PROTOZOA).

IO3

particular functions, these functions are performed by
any portion of the body, which is sometimes mouth,
-or leg, or arm, or stomach ;
" All things by turns, and nothing long."

If one of these creatures, which we call an Amoeba,
or Proteus, should be subjected to such a squeeze as
to separate it into two portions, each one starts ofif
on a separate existence, and becomes a Proteus on
its own account. On the other hand, two individuals
will meet sometimes so cordially that they will melt into
each other, and they twain literally become one flesh.
Nearly allied to the Amoeba is a little animal called
the "Sun-animalcule,"1 which may sometimes be
found in the
dirty scum floating on the surface of standing water, or
amongst Confervae and other
plants, " even
when the plants
are decomposed and the
water has become offensive."
They differ in
LARGE ACTINOPHRYS.
size, some being
{minute, others large enough to be seen by the naked
eye. The animal is of a flattened form, orbicular
Actinophrys sol.

104

PONDS AND DITCHES.

in shape, of a whitish colour, with rays or tentacles
diverging from every part of the body, which, Ehrenberg says " serve to move, to feely
and to catch." When the minute
Infusoria, with which such water
swarms, come in contact with these
tentacles they contract, and the
entangled Infusorian is absorbed
into the body of the animal. The
conjugation of these animals has
been described by several observers,
and various interpretations offered
in explanation of the phenomenon.1 One difference to be observed between the Amoeba and the
ACTINOPHRYS SOL. Sun-animalcule is, that in the latter
the locomotive organs, or tentacles,
are permanent, whereas in the former they are temporary. We have given figures of two species of these
Sun-animalcules.
A very little advance in organization is to be seen
in Difflugia, of which there are numerous species found amongst
Confervae, and dispersed over still
waters. This slight advance consists of an external horny covering
or shell, which is pitcher-shaped,:
with a narrow opening through
which the pseudopodia, or extemporized tentacles are protruded.
1

See Waller on Actinophrys sol in " Quekett Journal," No. 12.

LOW-LIFE (PROTOZOA).

105

Without lingering further amongst these minute
forms let us proceed to the examination of very visible
Protozoa as exhibited in Fresh-water Sponges. Of
these two are British, called respectively the River
Sponge,1 and the Lake Sponge.2 Although called
by these distinctive names they may often be found
growing in the same locality and within a short distance
of each other. It is true that they have been confounded, the one with, the other, for the want of due
care, but they are really so dissimilar, that there is no
excuse for the error. The Lake Sponge grows in
long, branching, lobed forms, and the River Sponge
in large unsymmetrical masses. Colour is variable
according to light, but generally the Lake Sponge isof a dark green, whilst the River Sponge is of a paler
yellowish or greenish tint.
The Fresh-water Sponge is commonly fished up from
ponds, reservoirs, and docks,
and may often be
found adhering
to the woodwork
of locks and
weirs. Throughout the course of
the Thames it is
tolerably COm- GEMMULES OF FRESH-WATER SPONGE.
mon. At one
time there were many persons who contended strongly
that the Fresh-water Sponge was not an animal but
Spongilla

fiuviatilis,

2

Spongilla lacustris.

io6

PONDS AND DITCHES.

a vegetable, and this position they held to be
strengthened by the fact that its green colour was
subject to the influence of light, and was chiefly
developed under that influence.
The sponge, in its fresh state, is by no means an
attractive object, it has no beauty in form or colour,
and its odour is scarcely inviting. The entire substance
consists of a gelatinous mass, called sarcode, in which
are imbedded numerous long, slender, firm, needleshaped bodies which are called spicules. The combination of the needle-like bodies forms a skeleton
which supports and gives firmness to the gelatinous
sarcode. The spicules, like needles of glass, are
composed of silex, or flint; and the sarcode is a
jelly formed of an agglomeration of bodies like the
Proteus into a mass. In the fresh-water sponges
we have a type of the great majority of marine
sponges, that is, a flinty or glassy skeleton of spicules
immersed in a mass of jelly. The soft sponges of
commerce are an exception, as they do not contain
such a flinty skeleton.
Enclosed within the substance of the Fresh-water
Sponge small seed-like bodies are commonly found,
to which the name of gemmules has been applied.
These contain spicules differing in form from those
composing the skeleton of the sponge. So much has
been written about these sponges of the fresh waters
and their life-history,1 that we need only refer to the
sources where more explicit information may be found,
1
Bowerbank, " British Spongiadse " ; Williamson in " Pop.
Science Review,'' vol. vii. p. I.

LOW-LIFE (PROTOZOA).

107

and especially to some observations on gemmules
and young sponges by Mr. J. G. Waller.1
If water which contains dead vegetable substances,
such as hay, grass, leaves, herbaceous stems, be exposed for a little time to the influence of the atmosphere, we shall find, on examining it with the microscope, that it contains swarms of active little creatures,
moving about in all directions, and it was to such
animals, found under such conditions, that the name
of Infusoria was applied in times past. At that
period, not so very remote, the name of Infusoria was given indiscriminately to a vast
number of organisms, some vegetable, some animal,
of which many now much better known and understood have been transferred to other positions, with
other names. As at present limited the Infusoria
possibly includes many disputed organisms, but it is
at any rate a very much smaller group than formerly,
and the term itself will probably soon pass out of use.
The Bell-flower animalcule, or Vorticella, is one of
the most attractive of the Infusoria, and may be
found in infusions of vegetable substances, or attached
to duckweed and other living plants. The body is
bell-shaped, and its mouth ornamented with a fringe
of vibratile cilia. This body is seated on a hollow,
long, elastic stem; which constantly contracts and
elongates alternately, so that the body is moved up
and down, whilst the base or lowest extremity is
attached to the object on which it is found. The
structure of the body has been thus familiarly explained. " The only familiar object with which I can
1

"Quekett Micro. Journ.," iii., p. 42.

io8

PONDS AND DITCHES.

compare it,"—the cup of Vorticella—" is a common
breakfast-cup, into which a circular piece of pasteboard has been inserted, so as to leave only the rim
of the cup visible. Suppose you were to cut a piece
of paper or cardboard to the shape of the cup at its
widest part, and make a hole in the cardboard a little

BELL-FLOWER ANIMALCULE.

to one side from the centre, you would imitate, to
some extent, the ' disk' as it is called, which closes the
wide aperture of the cup of Vorticella. The circlet
of cilia is disposed spirally upon the disk within the
lip, or rim, and is continued a little way into the

LOW-LIFE (PROTOZOA).

IO9

mouth or oral aperture, which is represented by the
hole in the cardboard that closes the aperture of the
cup." 1 The movements of these cilia cause a vortex,
into which minute animalculse are drawn, and thus
they pass into the body of the Vorticella.
There are many curious and interesting features in
the life-history of these little creatures, one is that
they are able to reproduce themselves by division;
that is, the cup divides itself down the middle and
down the stem. It constricts all the way down, and
the two opposite sides draw in gradually until they
meet each other, until in course of time two cups
and two stems are formed out of one, which separate
from each other and work as independently as if
they had never been united. Another mode of
increase is by the budding of young cups from the
side of the parent cup. The third mode is called
the encysting process. At a certain stage the
animalcule shrinks up into a ball, a gelatinous
substance exudes from its body and encloses it. In
this condition it rests for a time, whilst a swarm
of little oval animalcules are being formed in the
interior.
As the young brood grow, the outer
covering is distended until it can no longer resist,
when it bursts, and the imprisoned progeny are set
free.
A compound Vorticella, as it might be termed,
consisting of a common trunk, with the individual
infusoria attached to it by their thread-like stems, is
known by the name of Epistylis, of which there are
1

"Popular Science Review," i., p. 151.

HO

PONDS AND DITCHES.

several species; some attach themselves to the
hornwort and other growing plants, others are
parasitic on water-snails or
water-fleas, or other aquatic
animals. The pedicel is
rigid, and not contractile as
in Vorticella. This rigid
pedicel is characteristic of
Epistylis, which sometimes
is simple and unbranched
as in Vorticella.1
The largest infusorian,
however, is Stentor, which
is sometimes 1-2 5th of an
inch in length, and all the
species are visible to the
naked eye. They are excesSTENTOR MULLERI.
sively fond of fresh standing water, and lie sheltered
amongst plants where the water is still. The •" funnel
polyp,"2 as it was once called, when outstretched
is trumpet-shaped, with a crown or wreath of cilia,
which form an interrupted fringe; when contracted,
it throws out a gelatinous mass as an outer covering.
Dr. Wright says that the Stentor always secretes a'
gelatinous case into which it can retract when necessary. Stentors sometimes collect together in clusters and attach themselves to plants, hanging head
1
The most elaborately branched and tree-like Infusoria are
those named Carchesium.
2
Stmior MullerL

LOW-LIFE (PROTOZOA).

III

downwards. They are often to be found on duckweed, and also abundantly on the American Pondweed (Anacharis), independent of cold or ice. Mr.
Slack, describing his adventures amongst the Stentors, says :—" After leaving the Anacharis in a glass
jar for a few days the Stentors multiplied exceedingly, some clung to, the sides of the vessel in sociable
communities, others hung from the surface of the
water, and crowds settled upon the stems, visibly
changing their tint, as the Stentor green was much
bluer than the plant. Scores swam about in all sorts
of forms. Now they looked like cylindrical vessels
with expanding brims, now globular, now oddly distorted, until all semblance of the original shape was
lost. In many cases they were found in shining
tubes, but these were never so lively or green as the
free swimmers, but mostly of a dingy, dirty hue.
These housekeepers were more timid and cautious
than the roving tribe. They came slowly out of
their dens, drew back at the slightest alarm, never
took their tails from home, and only extended their
full length when certain not to be disturbed."1
It would not avail to attempt to describe all the
minute forms of ciliated infusoria which will be found
in dippings from ponds and ditches, or in any extempore aquarium which may be constructed out of a
glass jar, or even a basin, into which bottles of duckweed, pond-weed, and other pond gatherings are
emptied on the return home of the diligent collector.
The ovate bodies of Paramecium,3 covered with
1

Slack's " Pond Life," p. 146.

2

Paramecium aurelia.

112

PONDS AND DITCHES.

cilia, move about freely in all directions; the cilia
are disposed in lines, and Ehrenberg counted sixty
or seventy in some of the rows. They have been
called "slipper animalcules," from their flattened
form. Some interest attaches to these infusoria from
the fact that small dark crystalline bodies have been
seen in the frontal region, the real character and
functions of which do not appear, as yet, to have
been satisfactorily determined.
Another common form in infusions is Trachelius,1 also with
a ciliated body, and an elongated
upper lip or proboscis, so that
, the animal is pear-shaped, or
club-shaped, the proboscis being
represented by the stalk of the
pear. The mouth is seated on
one side at the base of the proboscis.
Very simple1 forms of infusoria
abound in stagnant water, especially those called Euglena, and
allied genera. The individuals are at times so numerous as to impart a green colour to the water. It is
uncertain whether these creatures should really be
associated with such more complex forms as we have
described, and, indeed, whether they should be
called infusoria at all. The creatures to which we
allude more particularly are spindle-shaped,2 if such
a definite character can be given to animals which
1

Trachelitis anas and Trachelius ovum.

2

Euglena viridis.

LOW-LIFE (PROTOZOA).

113

are constantly in the habit of distorting themselves,
sometimes shortening themselves nearly into a sphere,
and anon lengthening themselves into a narrow cylinder. Nevertheless, vary as they may, the head is
attenuated, and the tail pointed, and there is a long
whip-like filament, twice as long as the body, which
proceeds from the head. The whole creature is of a
bright green, except the two extremities which are
colourless, and a single bright red eye-spot, which
is seen most distinctly amidst the green.
It is difficult to see the flagellum, or
whip-like filament, proceeding from the
upper lip unless the water is coloured.
There is a supposed species which becomes blood-red when mature, but perhaps it is only a variety of the green
one.
The same water which contains the
very common Euglena, known to every EUGLENA.
microscopist, will also contain a few
solitary individuals of another species which differs
greatly in its habits and action. This latter loves
to dwell alone, seldom two are to be seen in company; whereas the former is most sociable, and
congregates by scores. Both are alike green, with a
bright red eye-spot, but here their similarity ceases,
at least in general external appearances. The sluggish Euglena, which is also the solitary one, remains
nearly in the same spot, seemingly holding on by its
tail, with the head-portion now moving in one direction and now in another. It is twice as long as its
sociable cousin, but has a habit of contracting itself

PONDS AND DITCHES.

H4

to half its length, then lengthening again, but in all
its motions so leech-like, so slow, that it seems difficult to believe in its bearing any relationship to the
vivacious common species. If looked at carefully the
body will be seen to be traversed by parallel lines of
little warts or elevations, running longitudinally down
the body rather obliquely, but when the creature
contracts itself, these lines are still more oblique, and
have a spiral appearance, hence its name.1 During
the slow gyrations" and deliberate twistings of this
species, which are very convenient for its examin ation
it will soon be discovered that its body is flattened,
or at the least it has the capacity of flattening itself;
but it does not revolve on its longitudinal axis, and
scarcely removes out of its place.
Yet another and more spirited member of the same
family is, it seems to us, found in every ditch. It
is green, with a red eye-spot, and a fiagellum or
whip proceeding from the head, but seldom to be
seen. This may be called "Leaflet Euglena."2 It
is just like a small green leaflet dropped from a
pimpernel, or some humble plant, into the water,
and suffused with life. In shape it is almost that
of a miniature codlin apple in outline, but "flat as
a leaf. As it floats about, it turns first on one
side and then on the other, and as to its floundershape there is no room for doubt. Nevertheless, it
has its upper side, for it does not reverse itself, and
this upper side is convex, like a lens, whilst the lower
surface has a very decided concave depression in the
1

Euglena spirogyra.

2 Euglena pleuronertes.

LOW-LIFE (PROTOZOA).

115

centre. The tail is colourless, and quite half as long
as the body. As if to carry out its similarity to a
leaf, there are two or three lines, resembling veins,
which rise from near the base of the tail and proceed
along the surface of the body towards the eye-spot
Not uncommonly the empty skins of this species,
retaining the original form, but without colour, will
be seen in proximity to the living individuals. In
size it is broader, but not so long, as the common
Euglena, and does not move quite so rapidly through
the water, but usually in a straight direction, as
if in pursuit of urgent business. Another Euglena
with a long cylindrical body,1 smaller than the sluggish
Euglena, and without longitudinal warted lines, crawls
about solitarily amongst Confervae and duck-weed.
All these four kinds are far from uncommon.
One of the most lively and interesting little creatures
to be found amongst Confervae, and other of the
fresh-water Algae, is the Infusorian to which the name
of Coleps2 has been given. We have often been
greatly amused in watching the movements of this
creature. In form it is not unlike a barrel, that is,
it is a short cylinder, with blunt ends, about twice
as long as its diameter; at the posterior extremity
are three or four short spines near the centre. Along
the surface are parallel lines of little warts, running
down the entire length, and furnished with cilia.
These ribs are united by transverse lines, so as to
form a kind of rectangular network. In the interior
are often seen spheres of green or brown opaque
1

Euglena

'deses.
I 2

2

Coleps hirtus.

Il6

PONDS AND DITCH%

matter, which roll about freely. The motion of these
animals is very active, but steady and sustained,
caused by innumerable vibratile cilia. As it moves,
it continues to roll over and over on its longitudinal
axis, the opaque spheres rolling in its interior. To
all appearance this little animal consists wholly of
the external network, the centre being as free as the
interior of a Volvox. A dozen of these organisms
rolling about at the same time across the field of
the microscope form a very amusing obj ect. Now and
then a specimen will be seen with a part of the upper
portion broken away, as if gnawed by a mouse, and
yet the animal rolls on as happily as if no accident
had befallen it. A still more interesting phenomenon
may also present itself, which serves to illustrate the
mode in which these animals increase themselves.
Here and there will be seen, in company with the
usual form, some individuals longer than the rest, but
with both extremities tails, that is, with the spiny
processes at both ends, and the centre constricted, as
if tightly girt by an invisible cord. If watched, these
double individuals lengthen more and more, until
they become just as large, and resembling two individuals soldered together by the head, and at last
separation takes place, and two Coleps swim away,
each on his own account. In this case one Coleps
has divided itself into two, a common mode of increase in the Infusoria, and to be seen equally in other
species. We have observed in these dividing, and
in the recently divided individuals, that the upper
portion, for at least one-third of the entire length is
destitute of warts, or apparent cilia, which afterwards

LOW-LIFE (PROTOZOA). ,

117

become developed. It is curious to see these double
animals floating about, now one end foremost, and
now the other, with equal vigour, though rather more
awkwardly, than do the single animals, and like them
rolling, like tubs, as they progress.
Very common in water which has stood for some
time, especially pond-water, containing water-weeds,
in decay, is an active vigorous Infusorian, darting
about in all directions, turning sharplyat right-angles as
it goes; now going a little way in one direction, then
turning sharply in another, and anon, rushing amongst
the filaments of Algae, never resting an instant, and
meanwhile causing a strong vortex in the water around
it. This is a Stylonichiay with a flat, nearly elliptical
body, the sides nearly parallel, the front extremity
truncate, and the lower extremity rounded. At the
latter end three or four stiff-pointed spines project a
little beyond the body. The under-surface, especially
near the front, is furnished with numerous, say from
twelye to twenty, flexuous, moveable, pointed processes,
not unlike legs, with a swollen base, resembling balland-socket joints, and these processes are in constant
activity. From the front, down one side, runs a row
of cilia. When the creature turns on its side it is
seen to be flattened, and then the flexuous processes
still more resemble legs, as it pushes amongst the
filaments of Confervae, apparently walking amongst
them, or pushing them aside. So rapid are all the
movements of this, and of many others of its tribe,
that it is by no means easy to obtatin a correct knowledge of all its parts. How are the legs (if we may
call them by this name) to be counted, when they are

n8

PONDS AND DITCHES.

ever in motion, and when before those on one side
have been guessed at, the creature twists itself round,
and is off again, far away, out of the field of the microscope? Of course if they are killed by the introduction of some fluid other than water, they become still
enough, but then so transparent and delicate are they
that all the organs seem at once absorbed, and we
gaze on something which resembles a little drop of
glycerine jelly, without legs, spines, cilia, anything
but a few minute clusters of granules. It is truly a
pursuit of knowledge under difficulties to make out;
the details of such an active little animal as a Stylonichia.
Not a whit less active is a rather shorter, and
broader oval, or almost rounded animal sometimes
found in company with the latter. This creature has.
a covering on one side, like a mussel with one shell,,
but the shell is as transparent as the thinnest of glass,
and is sometimes scarcely to be seen. Processes like;
legs, constantly moving, cilia, and spines, are alsopresent, but Euplotes1 is at once distinguishable
from any of the Stylonichia, by its rounded form, and
its thin and delicate carapace. Its movements and
habits, even to the trick of turning on its side, or
floating on its back, much resemble the former erratic
creature. We have had a dozen of these at the same
moment, darting about, as if engaged in a quadrille,
over the field of the microscope. One objection
which is not uncommonly urged against these Infusorians, by pond-hunters, is—that they are so smalL
Euplotes charon.

LOW-LIFE (PROTOZOA).

119

It is quite true that with less than what is termed " a
quarter-inch " objective, they are only moving specks,
but, when magnified, not less than three hundred
diameters, they furnish an inexhaustible fund of amusement and instruction. There is really no practical
difficulty in the examination of objects with such a
" power," especially when transparent, and a microscopist at all worthy of the name would work just
as well with that as with an " inch." An animal
only the two hundred and fiftieth, or even the
five hundredth of an inch long, has its history and
mystery, as great as that of a Hydra or Cristatella.
All that is lacking is patience, with perseverance to
trace it out.
Whilst we are digressing, a complete shoal of little
, Infusorians are passing before our eyes which are not
one-third the length of Euplotes. They are somewhat elliptical, little, transparent bodies, rather pointed
at each end, and covered with long cilia, which give
them their rapid movements. There is no other of
the common forms which has a motion like this small
Ptyxidium.1 It rests perfectly motionless for an
instant, then darts rapidly for a short distance in a
straight line. Then it rests again, and its long cilia
are seen moving slowly. In an instant it darts in
another direction, and as suddenly stops. Its whole
career is a succession of jerks. Before we had discovered the name it was entitled to, we named this
little fellow the " jerker," and it is by no means an
inappropriate name. They abound in stagnant water,
Ptyxidium crvulum.

120

PONDS AND DITCHES.

and in infusions, and may be traced through all the
stages of self-division. Nearly perfect, and ready to
part, a couple, joined end to end, may be seen
jerking amongst the rest as rapidly as any, and even
at times a rapid jerk will part them, and each will
jerk on, never to meet again. A small fragment of
fresh water Conferva, such as a Zygnema^ in a drop of
water will sometimes be accompanied by scores of
"jerkers."
Here we must leave the Infusoria, and the whole
of the Protozoa, to which this chapter is devoted, not
because we have exhausted them all, or even those
most common or interesting, but because we have
fulfilled our intention of exhibiting the characteristics
of some of the principal members of the class in
question, leaving the special introduction to each of
the genera and species to devolve upon those who
devote themselves as specialists to the full investigation of the different manifestations of animal and
vegetable life, in the various groups.1
After describing some of these objects in his own
popular and agreeable style, a writer on the low
forms of life thus concludes his memoir. " My
thoughts wandered back to the time when all these
strange phenomena, these evidences of the Creator's
presence in every atom, were still concealed from the
vulgar eye, and were known, more imperfectly even
than at present, and only to a privileged few. And
then they sought to penetrate into the future, and I
1
For special information, see Greene's " Manual of the
Protozoa."

LOW-LIFE (PROTOZOA).

121

could picture to myself the time when every workman at his bench would be able to recognise, in each
fragment of the material that passes through his
hands, an evidence of the Wise Power which controls his own operations, as well as those of nature.
And when I drew a comparison between the life of
one of "my own race, and that of a vorticella, I was
surprised to find how many men there are who seem
to take the animalcule for their model; whose birth,
growth, nourishment, wanderings, and, finally, whose
tranquil 'fixed' existence all resemble that of the
little bell-flower animalcule ? A sense of awe crept
over me when I recollected that, sooner or later, we
all sink to rest as does the vorticella, or the volvox
in its wintry stage; but gloriously above all these
thoughts rose the knowledge of the fact, that even
these senseless, soulless beings, do not die, but that
the germ retains its existence, and gives rise to fresh
forms of grace and beauty.
" ' Fair summer's bloom, and autumn's glow
In vain pale winter brave ;
Nor youth, nor age, nor wisdom know
A ransom from the grave.
" * But morning dawns and spring revives,
And genial hours return ;
Soman's immortal soul survives,
And scorns the mouldering urn.'"

" Popular Science Review," vol. i., p. 157.

122

PONDS AND DITCHES.

CHAPTER VIII.
HYDRAS.

THERE is an old story of the Greeks, in which we
were interested in school-days, which narrates that
there was a celebrated monster, to which the name of
Hydra was given, which infested the neighbourhood
of Lake Lerna. It had a hundred heads, according
to Diodorus, and as soon as one was cut off two
immediately grew up unless the wound was cauterized.
It was-one of the labours of Hercules to destroy this
monster, which he accomplished.
The modern hydra probably obtained its name from
this fable, but it was quite a different sort of animal,
although at one time its story created as much excitement in the scientific world as that of the monster
Hydra could have done amongst the Greeks. The
little animals to which this name is applied are solely
the inhabitants of fresh water, and are common
enough in ponds and ditches, adhering to aquatic
plants. If we take a tuft of the water-crowfoot, or
some other of the plants enumerated in our second
chapter, and place it in a vessel of water exposed
to the light, it is most probable that in half-an-hour
we shall be able to see the hydra in its native element.
No pocket-lens will be required to discover it, since
it sometimes attains nearly an inch in length, but as

HYDRAS.

123

the species most likely to be first observed is a green
one, nearly the colour of the plants to which it is
attached, some little care will be required in looking
for it until its form has become familiar.
After a little patient waiting, several of these little
creatures will be seen in different positions scattered
over the pond-weeds ; its body narrow and elongated,
of a cylindrical shape, attached by its base to the
plant; the outer extremity divided [into six or eight
long slender arms or tentacles, radiating from the body
like a star, moving up and down and in all directions,
and then retracting, until the whole animal seems to
be only a lump of green jelly; then in an instant all
is activity again. Such a creature is the Green Hydra 1
upon first acquaintance.
This little animal and all its operations may be
watched in a glass vessel with the unaided eye. It
is of a gelatinous nature, varying in colour according
to species, but in the green hydra it is of a grassgreen. The lower extremity of the body is expanded
a little in the form of a sucker, by means of which it
attaches itself at will; the upper or free extremity is
furnished with a mouth, around which the contractile
arms or tentacles diverge to the number of six to ten.
These tentacles are little hollow tubes closed at the
end, and the body is in like manner a hollow cylinder,
with an opening for a mouth at the upper end. The
whole surface of the body and tentacles is covered
with minute warts or elevations, which enclose what
are called "thread cells," containing the curious
Hydra viridis.

f 24

PONDS AND DITCHES.

urticating bodies, supposed to possess the power of
stinging.
They are voracious animals, feeding on water-fleas
and such small creatures as the water contains, which
are forced into the cavity of the body, digested, as far

GREEN HYDRA.—a &, mature ; c d, budding young.

as possible, and the indigestible portion expelled.
Large animals, such as a worm, are sometimes caught
within the embrace of the hydra's tentacles, and it
happens not unfrequently that one or two of the tentacles are broken off in the struggle, but in the end
the hydra usually succeeds, and the captive descends
into its distensible stomach. It is still an open question whether the little spines which are concealed in

HYDRAS.

125

the " thread cells" scattered over the hydra's body
are stings. Some assert that when an attack is made
these bodies are hurled at the prey and have the
power of benumbing it, so that it falls a ready victim.
Others deny this stinging power.1
" Tis a fine entertainment," writes Baker, "to behold
the dexterity of a polype in the mastering its prey,
and observe with what art it evades and overcomes
the superior strength or agility thereof. Many times
by way of experiment, I have put a large worm in the
very extremity of a single arm, which was instantly
fastened on it with its little invisible claspers. Then
it has afforded me inexpressible pleasure to see the
polype poising and balancing the worm, with no. less
seeming caution and judgment than a skilful angler
shows when he perceives a heavy fish at the end of a
single hair line, and fears it should break away. Contracting the arm that holds it by very slow degrees,
he brings it within the reach of his other arms, which
eagerly clasping round it, and the danger of losing it
being over, all the former caution and gentleness are
laid aside, and it is pulled to the polype's mouth with
a surprising violence."2
The hydra is mostly celebrated for its marvellous
powers of reproduction. This is in the ordinary way
achieved by budding from any part of the body,
except the tentacles. Sometimes two or three are
proceeding at one time from the same individual. A
little tubercle rises on the body of the parent, this
1
2

See Lewes, "Sea-side Studies," p. 142.
Baker, "History of the Polype," p. 65.

126

PONDS AND DITCHES.

enlarges every hour, lengthens, and ultimately tentacles appear at the apex, but no sooner are the young
thus furnished than they commence catching prey on
their own account, whilst still attached to the body of
their mother.
" I t is not unusual to behold the young one and
the old one struggling for, and gorging, different
ends of the same worm together. In the summer
months the young are budded after the rate of
twenty in a month, and buds have been seen to
develope on the bodies of the young ones, whilst still
attached to their parent. The second mode of reproduction takes place in the winter, in the ordinary way,
from eggs. The third is an accidental mode, but
the most curious of all.
" If the body is halved in any direction, each half
in a short time grows up a perfect hydra; if it is cut
into four or eight, or even minced into forty pieces,
each continues alive, and developes a new animal,
which is itself capable of being multiplied in the
same extraordinary manner. If the section is made
lengthwise, so as to divide the body into two or more
slips, connected merely by the tail, they are speedily
resoldered like some heroes of fairy tale, into one
perfect whole; or if the pieces are kept asunder each
will become a polyp; and thus we may have two or
several polypes with only one tail between them ; but
if the sections be made in a contrary direction—from
the tail towards the tentacles—you produce a monster
with two or more bodies and one head. If the tentacles—the organs by which they take their prey, and
on which their existence might seem to depend—are

HYDRAS.

127

cut away, they are reproduced, and the lopt-off parts
remain not long without a new body. If only two or
three tentacles are embraced in the section, the result
is the same, and a single tentacle will serve for the
evolution of a complete creature. When a piece is
cut out of the body, the wound speedily heals, and,
as if excited by the stimulus of the knife, young polypes
sprout from the wound more abundantly and in
preference to unscarred parts; when a polype is
introduced by the tail into another's body, the two
unite and form one individual; and when a head is
lopt off, it may safely be engrafted on the body of
any other which may chance to want one. You may
slit the animal up, and lay it out flat like a membrane,
with impunity; nay, it may be turned outside out, so
that the stomach surface shall become the epidermis,
and yet continue to live and enjoy itself. And the
creature even suffers very little by these apparently
cruel operations—
' Scarce seems to feel, or know
His wound,'

for before the lapse of many minutes, the upper half
of a cross, section will expand its tentacles and catch
prey as usual, and the two portions of a longitudinal
division will after an hour or two take food and retain
it."*
It is scarcely to be wrondered at that when these
curious facts were first made known, the scientific
world was amazed, and popular writers turned them
into ridicule. The leading men of the learned
1

Johnston, « British Zoophytes," vol. i. p. 135.

128

PONDS AND DITCHES.

societies were daily experimenting on these poor
creatures, and transmitting them to one another from
distant countries by careful posts, and as most precious gifts, and even ambassadors interested themselves in sending early intelligence of the engrossing
theme to their respective courts.
Besides the above-named green species, which has
the tentacles rather shorter than the body, there is
an orange-brown hydra, 1 common enough round
London, with more slender tentacles, longer than the
body, and numbering from seven to twelve.
The third species is brown, 2 the lower part of the
body suddenly attenuated into a kind of stalk. The
tentacles are from six to eight, very long and thin,
extending to several times the length of the body.
In some localities this seems to be as common as
the green one. All are found under similar conditions, and in the same places, so that it is by no
means unusual to find them mixed together in the
same gathering. There is no difficulty whatever in
preserving them alive in jars of water containing
aquatic plants, to which water-fleas and other minute
animals may be added as food. The hydra is capable of going without food for some time, weeks it is
said, growing thin meanwhile, but still active. They
need not be put to such inconvenience, for small
shreds of fresh meat will always be welcome, in the
absence of living prey. None of the experiments to
which we have alluded need repetition, they have all
been demonstrated and confirmed, and the poor
1

Hydra vulgaris.

2

Hydra fnsca.

HYDRAS.

129

hydras should now be permitted to enjoy life in
peace.
Marine animals of the Hydra type are extremely
common all around our coasts, and are cast up by
every tide; but in these instances a number of
animals are found living in community within their
horny and branched cells, attached to each other in
the form of corallines, or like a tuft of seaweed, and
commonly known by the name of zoophytes. Only
one of these community-loving, or sociable hydra, is
to be found in fresh water, and that so rarely that it
need only to be named as an
example of the sociable habits of
some species, but without any
hope that the majority of our
readers will ever have the good
fortune to meet with it.
ThisCordylophora 1 is branched,
and plant-like between two and
three inches high, very slender,
and branched in a zigzag manner,
with short opposite branches.
The polyps emerge from orifices
.at the ends of the branches, each
head with from twelve to fourteen delicate tentacles like gossamer threads waving in the
water.
It was first found at Dublin,
CORDYLOPHORA.
in the water of the Grand Canal,
Cordylophora lacustris*
K

13°

PONDS AND DITCHES.

attached to an old boat. It has since been found
in some of the London docks, on a piece of an
old boat at Tipton, on an old boat in the Stourbridge
Canal, in a cistern at Kensington, and at King's
Lynn.
Few in number as are the species of fresh-water
hydra, they may be taken as the representatives of the
class Hydrozoa, and in some sense of its allied class,
the Actinozoa. These scientific names convey but
little meaning to the uninitiated, but when we name
some of the animals included in both, it will be seen
what relationships belong to our little hydra, and how
respectable are its family connections. The former
class has not only the zoophytes of the sea-shore
for its members, but also the curious Medusa
and Jelly-fish; and the latter includes not only
the Sea-anemones, but also the tiny builders of the
coral-reefs, with a history running backwards through
fossil-corals to the remote Silurian age.
" And catching prey on every side, with feelers
Countless as sunbeams, slight as gossamer ;
Ere long transfigured, each fine film became
An independent creature, self-employ'd,
Yet but an agent in one common work,
The sum of all their individual labours.
Shapeless they seemed, but endless shapes assumed ;
Elongated like worms, they writhed and shrunk
Their tortuous bodies to grotesque dimensions;
Compress'd like wedges, radiated like stars,
Branching like sea-weed, whirl'd in dazzling rings;
Subtle and variable as flickering flames,
Sight could not trace their evanescent changes,
Nor comprehend their motions, till minute

HYDRAS.

And curious observation caught the clue
To this live labyrinth,—where every one,
By instinct taught, perform'd its little task,;
To build its dwelling and its sepulchre." l

Montgomery's " Pelican Island."
K 2

13 B

T32

PONDS AND DITCHES.

C H A P T E R IX.
FRESH-WATER POLYZOA.

No account of the inhabitants of still waters could be
considered complete which did not make some allusion
to those animals which are the pride of the pondcollector, and known generally by the name of Polyzoa.
This kind of animal prevails largely in salt waters,
but the fresh-water representatives
are wholly distinct as species, and
are considered as a group which
may be studied without particular
reference to their marine relatives.
The general character or type of
a Polyzoon is admirably summed
up by Professor Allman in the
fewest words :—" Let us imagine
an alimentary canal, consisting of
oesophagus, stomach, and intestine,
to be furnished at its origin with
long ciliated tentacula, and to
have a single nervous ganglion
TYPICAL POLYZOON. situated on one side of the oesophagus. Let us now suppose this
canal to be bent back upon itself towards the side of
the ganglion so as to approximate the termination to
the origin. Further, let us imagine the digestive tube

FRESH-WATER POLYZOA.

!33

thus constituted to be suspended in a fluid contained
in a membranous sac with two openings, one for the
mouth, and the other for the vent, the tentacles alone
being external to the sac. Let us still further suppose
the alimentary tube, by means of a system of muscles,
to admit of being retracted or protruded according to
the will of the animal, the retraction being accompanied by an invagination of the sac so as partially or
entirely to include the oral tentacles within it, and if
to these characters we add the presence of true sexual
organs occupying some portion of the interior of the
sac, and the negative character of the absence of all
vestige of a heart, we shall have perhaps as correct an
idea as can be conveyed, of the essential structure
of a Polyzoon in its simplest and most generalized
condition."l
Some of these animals delight in sub-alpine lakes
or rapid rivulets, where they adhere closely to the
under-surface of stones, while others prefer slow
rivers or the still waters of canals and ponds. One
species has been found as deep as four feet in the
water, but usually they occur at much less depths,
and frequently at the very surface, attached to the
under-side of the leaves of floating plants. With one
exception they are destitute of locomotion, being
permanently attached to some fixed object; and all
with this solitary exception impatient of the light,
withdrawing as much as possible to the most shaded
and gloomy spots.
This is the barest skeleton of the character of the
1

Allman, " Fresh-water Polyzoa," p. 7.

T

*34

PONDS AND DITCHES.

ffresh-water Polyzoa, to fill up the details of which
there is ample material in the excellent volumes which
have been published on the subject, but even an
abstract of which would go far to fill our little volume.
The best substitute we can offer is to indicate the
animals themselves, so that by collecting and studying
them our readers may compensate for our deficiencies.
We have said that with but one exception these
creatures were permanently attached; and this one
exception of a travelling Polyzoon we have in the
Cristatella,1 which creeps over the stems and leaves
of aquatic plants, in clear ponds, delighting to bask
in the sunlight.
The moving Cristatella is an entire colony, and not
a single individual, the Polyzoa being of very sociable
habits; and this colony is united together into a body
of an oval shape, rounded above, and flattened below,
temporarily adhering by means of the under surface.
On the upper, rounded surface, are the openings
through which the crests of the Polyps emerge, and
these are arranged in three regular lines around the
margin, with a clear space in the centre. In the
centre of the under-side is a disc, corresponding to a
foot, by means of which the colony is moved, or
moored.
Usually these colonies are not more than from
Jhalf-an-inch to an inch in length, although they have
been known to attain two inches, with a width of
.about one-eighth of the length. It is a splendid
<object to contemplate when in full expanse, the head
1

Cristatella mticedo*

FRESH-WATER POLYZOA.

135

of tentacles thrust out at every opening, and shining
in the sun. Contrary to the usual habit of these
animals, the Cristatella appears to love to thrust out
and display its tentacles, and if momentarily disturbed
it retracts them, only to thrust them out again as
soon as the danger is past.
The crown of tentacles which is thrust from the
openings in the fresh-water species has nearly the
form of a horse-shoe, from which the tentacles arise,
but in marine species the form is usually circular.
Each tentacle is a closed tube with a row of moveable
cilia along each side, vibrating towards the apex on
one side, and towards the base on the other. These
tentacles are about eighty in number in Cristatella,
being more numerous than in any other British species.
Singular bodies are at some seasons of the year
found associated with the Polyzoa, which have been
called statoblasts; although at one time erroneously
supposed to be eggs, they are really a kind of reproductive buds. They are oval or round flattened bodies
with a horny shell, often covered with spines, but
sometimes naked, which at length open, and permit
of the escape of a young Polyzoon. In Cristatella
the statoblasts are scarcely one-thirtieth of an inch in
diameter, circular in outline, and surrounded by a
fringe of slender spines, double-hooked at their
extremities.
Another British species is Lophopus 1 which has
been the longest known of any species in this country,
and was figured under the name of "Bell-flower
Lophopus crystallinus.

*3 6

PONDS : AND DITCHES..

LOPHOPUS.

a/i, mouth : b, oesophagus ; c> stomach ; d, intestine; e, muscles £
/,. statoblast; ms lophophore ; o, vent; / , parasite.

FRESH-WATER POLYZOA.

137
1

Animal" one hundred and thirty years ago.
It
occurs in ponds and ditches attached to duckweed,
burrweed, and other aquatic plants, but avoiding as
much as possible direct sunlight. Although easily
detached from its support it has no power of locomotion, and being one of the largest of the Polyzoa, is
the one most easily studied. Johnston says that it
occurs in stagnant waters, " especially such as are
tinctured with iron in solution," being chiefly developed
in the autumn.
"They dwell together," wrote Baker, "from the
number of ten to fifteen in a filmy kind of mucilaginous or gelatinous case, which, out of the water
has no determined form, appearing like a lump of
slime, but when expanded therein resembles nearly
the figure of a bell with the mouth upwards ; and is
usually about the length of half-an-inch, and a quarter
of an inch in breadth or diameter. This case is very
transparent, all the motions of its inhabitants may be
discerned through it distinctly. The bells or colonies
are to be found adhering to the large leaves of duckweed and other aquatic plants; and may easiest be
discovered by letting a quantity of water with duckweed in it stand quietly for three or four hours in
glass vessels, in some window, or other place where a
strong light comes, for then if any are about the
duckweed they will be found on careful inspection
extending themselves out of their cases, spreading
their plumes, and making an elegant appearance."
Mr. James Fullager, to whom we are indebted for
1

Baker, "Employment for the Microscope," p. 306, pi. 12.

138

PONDS AND DITCHES.

our illustration, has thus described the animal, with
reference to the wood-cut, the letters referring to the
parts under description.
This large Polyzoon is a most interesting object for
the microscope, and being transparent, is very available
for examination, as the formation of the statoblasts ( / )
can be seen in different stages of growth, from their
first appearance as a little swelling, when they are
quite colourless, to their perfect form, when they
become detached and fall free in the perigastric space
(/), having become gradually coloured, the centre of
a dark brown and the margin a rich yellow. The
process of their propagation by gemmation or budding,
by which young ones are added to the existing colony
of living Polyzoa, can be plainly seen; while the
statoblasts (/) are designed to propagate the species
in the following spring, and are liberated from the
Polyzoon at its death, when the transparent sac is
decomposed, and the statoblast escapes and sinks to
the bottom of the water.
The perfect transparency also enables us to witness
the internal operations of their system. The action
of the stomach in the process of digestion can be
observed with great clearness. The contents are seen
at times to consist of small desmids, and other discshaped and globular bodies, together with decayed
vegetable matter, &c.' The action of cilia on the
expanded tentacles causes a current of water to set
in towards the mouth (a, Ji) bringing with it the
food required; and if in the vortex thus formed there
should be any large and objectionable pieces, they
are prevented from entering the mouth by a quick

FRESH-WATER

P0LYZ0A.

I

39

lashing motion of the tentacles, which rejects and
throws them out of the reach of the vortex. The
accepted morsel passes directly into the sesophagus
(b), from thence into the stomach (c), where it is
digested by the up and down motion of a contracting
and expanding nature of that organ. The lower part
of the stomach at intervals is seen to be contracted
somewhat in the shape of an hour-glass, in which for
a moment part of the contents of the stomach are
retained, and then again released to mix with the rest.
After being subjected to the action of the stomach
for some time, the alimentary matter is delivered by
degrees into the intestine (d), from whence it is
expelled through the vent (o), in the form of oval, or
egg-shaped pellets.
The perigastric space (/), is filled with a clear fluid,
which also extends up the lophophore (m). By the
movement of these bodies it is evident that there is
a constant rotating motion in this transparent fluid,
by which these particles are kept in a perpetual whirl
from one part to the other, and at times with great
rapidity. No doubt this motion is produced by
vibratile cilia on the interior of the body, though not
observable. In some of the colonies of the Lophopus
there are a number of globular bodies, varying in size,
up to that of an ordinary Volvox. These bodies are
considered to be parasitical, as they do not appear to
have any necessary connection with the economy of
the Polyzoon in whose interior they occur. This
would appear to be the case from the fact that in
some colonies not one of them is to be seen, while
in others they are very numerous.

140

PONDS AND DITCHES.

In one instance of a colony under my observation
they were increased in such numbers of all sizes that
they entirely filled the perigastric space (/), forcing the
smaller particles up even into the lophophore (///), and
ultimately bursting the whole colony, and escaping
into the water, when all motion in them ceased, and
they soon disappeared altogether. When they are
few in number and of various sizes in the animal,
they form a novel and pleasing sight as they are
carried up and down by the current in the perigastric
space ; at times revolving with great rapidity on their
own axis, and at the same time round one another.
Frequently a group of five or six may be seen revolving
together. Some of them are perfectly clear, others
are partially covered with small globular forms of a
brighter appearance than the globe itself. The largest
of them are sometimes marked with irregular patches
of various shapes, and, as they revolve on their axes,
it gives them the appearance of a miniature world.
A few show an opening (p>), by which they are seen
to be empty hollow globes, but what they really are is
not known.
On being alarmed the Lophopus quickly retracts
within the transparent cell, and again protrudes when
all is quiet, unfolding its beautiful crown of tentacles,
in the course of which movement the action of the
muscles (e) is plainly seen. The expanding of the
tentacles immediately on the protrusion of the polypide
from its cell is one of the most pleasing sights that
can be presented to the observer, as the cilia with
which they are studded are instantly in full play,
passing up on one side of the tentacle from the base

FRESH-WATER POLYZOA.

141

to the tip, and down the opposite side, like an endless
chain, thereby forming the vortices in the water by
which the particles of food are brought to the mouth.
Sometimes the colony consists of from six to twelve
polyps, and will divide into two colonies, commencing the division at r, and slowly separating down
to the point where it is fixed to the plant, each part
moving in opposite directions. They then propagate
by gemmation or budding. This process is very
interesting to watch, from the first appearance in the
parent, to the issuing of the young from the newlyformed cell. When the minute tentacles of the young
are exerted, they form a beautiful contrast to the
fully developed tentacles of their parents. Though
small, yet the same functions are visible in relation to
digestion, &c, as in the older ones. 1
Transparent as these creatures are, they are covered
by a still more transparent envelope, which might
escape observation unless some extraneous objects
happened to be attached to it, as is often the case.
The muscles of the creature when the polyp is fully
extended may be seen drawn tight, and have the
appearance of fine glass threads. When the animal
is retracted within its cell, the muscles (e) are relaxed
and bent.
Fortunately these colonies may be collected, and
preserved in active and vigorous life, so as to be continually under observation day by day for months, if
moderate care be exercised as to water supply, and
the maintenance of natural conditions.
Of Alcyonella, three species have occurred in
1

"Science-Gossip," 1874, p, 270.

142

PONDS AND DITCHES.

Britain, but only one is at all common.1 It has been
found abundantly in the Regent's Canal, and other
canals, and in the London docks attached to floating
timber. It seeks obscure places, and attaches itself
to stones, timber, and submerged branches, in stagnant and slow-running water. The brown funguslike masses sometimes weigh upwards of a pound,
of a very irregular lobed shape, surrounding the twigs
and branches to which they may be attached.
il
When a living specimen is examined in the
water, its whole surface seems covered with a whitish
down, which a slight examination shows to be occasioned by the protrusion of innumerable polypides;
when removed from the water the polyps shrink
back into their cells, and the surface then seems
covered with a gelatinous investment, caused by the
soft, papilla-like extremities of the tubes. These
extremities contract no adhesion to one another, like
the rest of the tubes, and the ectocyst, as it passes
over them, becomes very delicate and transparent;
in dead specimens they shrivel up and disappear,
and then the surface of the mass presents a multitude
of closely-applied hexagonal or pentagonal orifices. The
whole production now assumes the appearance of a
spongy, honeycomb-like mass, and this has not unfrequently been mistaken for a fresh-water sponge. A vertical section shows it to be composed of a vast number
of tough, horny-membranous branched tubes, closely
adherent to one another, and each opening on the
surface by one of the angular orifices just mentioned.
Imperfect transverse septa may be seen at the origin
A Icyonclla fungosa.

FRESH-WATER POLYZOA.

145

of many of the branches. The tubes, towards the
end of summer, are loaded with mature statoblasts,
which escape in great numbers into the surrounding
water." 1
The general appearance of the polyp masses o
Alcyonella, when drawn out of the water, are so
uninviting, if not repulsive, that we can scarcely
wonder at their being so little known, or their interesting features so faintly recognised.
No less than ten species of Plumatella have at
different times been found in the British Isles, but
of these it will suffice to mention one, which might
be called the Common Plumatella, 2 as a type of the
rest. It is found on the surface of stones, turned
away from the light, in streams, and on the underside of floating leaves in ponds. The size is variable,
and Professor Allman says that he has seen it radiating over a space of upwards of twelve square inches
on a flat stone, and of one variety with branches
three inches in length. Unlike the forms above described, this does not assume compact masses, but
the dwelling of the colony, in its ordinary form,
creeps over the object to which it is attached, in a
branched, confervoid manner, radiating from a common centre. Perhaps no Polyzoon is more variable
than this, but in all it is beautiful. In some places it is
very abundant, and is generally distributed throughout
England. The openings are placed at intervals along
the principal branches, singly, or occasionally in
twos or threes, and from these the feathery crests
of the Plumatella emerge when the animal is
1

Allman, p. 89.

2

Plumatella repeits.

144

PONDS AND DITCHES.

PLUMATELLA.

perfectly undisturbed,
but it is peculiarly
timid, and the crests
are immediately withdrawn upon the slightest disturbance. In
the variety of this
Plumatella, which
some have considered
as a distinct species,
instead
of
the
branches of the polypidom creeping along
on the surface of the
plant, to which they
are more or less attached, they are quite
free, and form a somewhat entangled bushtuft; the essential characteristics of the enclosed animal is alike
in both. The number
of tentacles in each
crest of the common
Plumatella is sixty,
but in some of the
other species it is as
low as forty. In structure and movements
they correspond with
the other fresh-water
polyzoa.

FRESH-WATER POLYZOA.
1

145

Fredericella is another of the branched tubular
polyzoa, with the branches distinct from one another,
and the openings terminal at the ends of the branches.
This seems to be particularly attached to canals, having been found plentifully in the Regent's Canal at
London, in the Grand Canal, Dublin, and in the
Union Canal, Edinburgh. It is attached to submerged stones and the leaves of
aquatic plants, preferring shady
situations. This is one of the
most widely distributed of the
fresh-water polyzoa, having been
met with abundantly in the three
kingdoms.
The Polypidum is
partly attached and partly free,
the adhering portion often extending for several inches, and
sending
off
numerous
free
branches an inch in height. It
is rather horny, and of a brownish
colour. The crown is rather more
orbicular than usual, and the
number of tentacles twenty-four,
which, when expanded, form a
FREDERICELLA.
bell-shaped crest. Professor Allman says of this species,—" I have met with it
during the whole of the spring, summer, and autumn months, both in standing waters and rivers,
generally avoiding direct exposure to the daylight
though not so decidedly a lover of obscurity as
several other species. The tentacular plume is, even
1

Fredericella sultana.
L

146

PONDS AND DITCHES.

to the naked eye, an object of extreme elegance, and
we can easily participate in the feelings which must
have actuated Blumenbach when he bestowed on
this little animal the imperial designation it has since
borne. It can be kept alive and healthy in a pail
of pure water, and when undisturbed the polypides
will readily issue from their cells, and display their
plumy crowns. A large branch thus studded with
the campanulate crests of the polypides is an object
which, in elegance, can hardly be surpassed, and
with these strange sentient flowers instantly retreating on the approach of danger, and, when all is once
more quiet, again coming forward in their beauty,
presents a spectacle not easily forgotten."1
The Paludicella2 bears some resemblance to a
creeping coralline, running over submerged stones
to the extent of one or two inches, giving off straight,
rigid branches, either singly or in pairs; every branch,
and portion of adherent trunk, consists of clubshaped joints attached end to end, so as to present a
chain-like appearance. The openings are on one
side, near the wider ends of the club-shaped joints,
and terminate in small tubes which project from the
joints. The colour of the polypidum, when old, is
dark brown.
The crown is circular, from which arise the sixteen
tentacles, in a perfectly funnel shape. In all its
features there is such a manifest distinction between
the Paludicella and all the other fresh-water forms,
that there is scarcely a possibility of mistaking it.
1

Allman, p. 112.

a

Paludicella Ehrtnbergii,

FRESH-WATER POLYZOA.

147

The animal is very timid, and it may be observed
for hours before it ventures to protrude from its cell,
and then it is often visible only
for a few seconds at a time. It
is so great a lover of obscurity that it has only been
found in situations that are
not exposed to direct daylight;
the finest and most luxuriant
specimens having been obtained beneath the arches of
viaducts on the Grand Canal
at Dublin, and in similar situations elsewhere. It is most
abundant during summer and
autumn.
There seems to be very little
doubt that these beautiful microscopical animals are by no
means so plentiful around London as they were some few
years ago. It is not improbable that the increased
popularity of the microscope, Saturday half-holidays,
and the excursions of microscopical and natural history societies have combined to produce this result.
Let us hope that in their destruction they have left
some salutary lessons behind them.

L 2

148

PONDS AND DITCHES.

C H A P T E R X.
ROTIFERS.

T H E older naturalists recognised amongst aquatic
animals a group of singular creatures, which appeared
to them to differ from all others in bearing about
their heads or upper extremities certain organs, constantly in motion, and resembling wheels. These
they called " wheel-animalcules." The modern name
of Rotifera perpetuates the old romance of " wheelbearers," and yet the organs in question are not
wheels, but simple expanded discs, varying in form
according to the species, having the margin fringed
with one or more rows of delicate hairs, which by
their continual and successive motion around the
disc, certainly had the appearance of rapidly revolving
wheels. The conceit is dead, but the animals still
survive, and we have as inhabitants of ponds and
ditches, as well as of slow running streams, and a
few marine, a great number and variety of Rotifers,
which seem to bear a wheel at their heads. This
little group has been a great puzzle to the systematists, and even to this day there is no unanimity amongst them as to the precise place in
creation which the " wheel-bearers " should occupy.
Some say that they link with the shrimps and lobsters,
others with the worms. This uncertainty will in no

ROTIFERS.

way influence
our
operations, and we
shall proceed to indicate what sort of
creatures these Rotifers are, some of the
places in which they
love to dwell, and
what the interest they
possess for the rambler in search of the
notable things in the
water.
Converse for halfan-hour with any one
of the somewhat numerous class of enthusiasts who spend their
Saturday
afternoons
in exploring ponds
and ditches, and you
will not fail to hear
something of Stephanoecros} And who is
Stephanoceros ?
We
must confess that it is
only a Rotifer with a
big name, but a splendid one it must be
confessed, and hence
the ambition of every

149

T H E CROWN ANIMALCULE.

Stephanoceros Eichhornii.

ISO

PONDS AND DITCHES.

fresh-pond hunter is to find Stephanoceros, or, as it has.
been called, the " Crown Animalcule." Ask a party
of Quekett Club excursionists, starting for a trip to
the ponds, what they expect to find, and the answer
will be Stephanoceros. Turn over the leaves of any
volume professing to be a guide to the microscopist,.
and amongst desirable animals you will find mention
of Stephanoceros. Unfortunately, this is a rather
erratic individual, and where found plentifully in a
pond during one year not a single one may be found
in the next. Let us attempt its portrait.
The creature reaches a length of one-fifteenth of
an inch, and therefore is distinctly visible to the
naked eye. In its adult condition it becomes permanently fixed on aquatic plants. The lower portion,
which is attached, consists of a gelatinous envelope,
like a transparent cylindrical case, into which the
animal can retract itself at will. When expanded,,
the upper portion which protrudes from the case is
terminated by five spreading arms, and these arefurnished throughout with long hairs, or cilia, which
almost imperceptibly produce waves of motion from
end to end. These expanded arms with their cilia
form a kind of network cup, in the centre of which
at the bottom is the mouth. " There is a manifest
vortex in the enclosed area, for small infusoria approaching are presently drawn in and are driven
about in the space. They can enter readily at all parts
between the arms, but cannot get out; for if one
approaches the arms from within it is seen instantly
to be shot back towards the centre. I perceived,"
writes Mr. Gosse, " after some careful watching that.

ROTIFERS.

i5*

the motion was caused by the seta, a. minute tremulous, and, as it were, spasmodic wave, being seen to
run along the nearest pencils at the instant. It is
clear, then, that the setce crossing each other serve
as a living net, which admits the prey to enter
without resistance, but if touched from within vibrates
in such a way as to jerk the touching body with
considerable force towards the centre of the contained area. When once the prey passes downbelow the area into the mouth-funnel, which is
formed by very contractile walls, a slight constriction takes place in the neck, which has the
effect of forcing the monad down to the mouth of
a capacious crop which lies all across the upper
part of the body. Here a sort of swallowing motion
is seen, and the prey passes with a gulp down into
the cavity."1
The lower part of the body is prolonged into a
slender foot which passes through the centre, or,
rather, is surrounded by the transparent envelope,
and is attached to the object on which the Stephanoceros has fixed itself. The slender foliage of the
water milfoil2 is a favourite home of this species,
but it has been found on other plants, and on the
slender roots of the willows which run into the water.
It is considered a voracious feeder, and will swallow
scores of infusoria, one after the other. When found
it should be taken home, carefully attached to the
plant on which it was gathered, of course in a bottle
of water, and may be kept alive for some time in
1

" Popular Science Review," vol. i., p. 34.

2

Myriophyllum*.

152

PONDS AND DITCHES.

jars of water exposed to the light, but guarded from
the hot rays of the sun. Fragments of fresh-water
plants may be occasionally added, but these need
not be rooted, and in this manner the strange creature
may be kept five or six weeks, and afford continual
instruction and amusement.
Similar, but yet different, is another of the large
rotifers which become permanently attached to aquatic
plants. This is the Floscularia;l it may be one of two
or three species, but the general appearance and
habits of all are the same. Like the Stephanoceros
this has also a delicate thin transparent envelope
surrounding the lower portion of the body and the
foot. So delicate is this membrane that it is often
to be seen only with the greatest difficulty. The
principal difference which will become manifest is
that the lobes or arms are very short and knobbed
at the end. The long cilia are clustered upon these
knobs, from which they radiate in all directions.
The animal is smaller than the Stephanoceros, but
many consider it even more beautiful. The number
of lobes is five, and of the long cilia which beset
each lobe from forty to fifty have been counted on
each knob. When the Floscule draws itself into its
case all the cilia are thrown upwards in the same
direction, parallel to each other, so as to form a
single pencil. "They are motionless when expanded,
but, while protruding, and in the instant of expanding,
the pencil is seen to be agitated with a close and
rapid thrill or wave, which runs along it, and looks
1

Floscularia ornata, or Floscularia cornuta, see
piece.

frontis-

ROTIFERS.

153

much like the flickering of a candle-flame. It ceases
the instant the disc is expanded." 1
This creature will be met with on the leaves of
submerged plants, such as the water crowfoot, but a
little experience is necessary to distinguish them.
Mr. Slack thus gives advice which will be found
useful:—" When the floscules, or other tubiculous
rotifers are specially sought for, the best way is to
proceed to a pond where slender-leaved water-plants
grow, and to examine a few branches at a time in a
phial with a pocket lens. They are all large enough
to be discerned in this manner, and as soon as one
is found others may be expected, either in the same
or in adjacent parts of the pond, for they are gregarious in their habits. With many, however, the
first finding of a floscule will be an accident, as was
the case last April, when a small piece of myriophyllum was placed in the live box, and looked over
to see what it might contain. The first glimpse
revealed an egg-shaped object, of a brownish tint,
stretching itself upon a stalk, and showing some
symptoms of hairs or cilia at its head. This was
enough to indicate the nature of the creature, and
to show the necessity for a careful management of
the light, which being adjusted obliquely, gave quite
a new character to the scene. The dirty brown hue
disappeared, and was replaced by brilliant colours;
while the hairs, instead of appearing few and short,
were found to be extremely numerous, very long, and
1
For a fully detailed account of this animal see also
" Popular Science Review," vol. i., p. 160.

PONDS AND DITCHES.

*54

glistening like delicate threads of spun glass."l He
then goes on to describe the floscule, but our space
will not permit us to follow him.
The last of the fixed Rotifers to which we purpose
alluding is the Melicerta? and with this we are introduced to quite another type
of tube - dwellers. So much
has been written of the " tubebuilders " that it is difficult to
add anything, or even to describe them but by repetition ;
hence we cannot do better than
quote one of Mr. Gosse's excellent descriptions. "Imagine,
then, a little tube about i-3oth
of an inch high, slightly widening at the top. It stands up
from the surface of the leaf
erect, being affixed by the base,
which is sometimes dilated; the
mouth being uppermost. This
tube is of a dark yellowish or
reddish-brown hue, and is found
MELICERTA.
to be composed of a multitude
of round pellets, set very regularly in a sort of
mosaic, apparently agglutinated by a cement insoluble in water. But while we gaze, a curious
object is slowly protruding from this tube. A complicated mass of transparent flesh appears, involved
1
2

" Marvels of Pond Life."
Melicerta ringens and other species.

ROTIFERS.

155

in many folds, displaying at one side a pair of hooked
spines, and on the other two slender truncate processes projecting horizontally. As it exposes itself
more and more suddenly two large rounded discs
are expanded, around which, at the same instant,
a wreath of cilia is seen performing its surprising
motions. Often the animal contents itself with this
degree of exposure, but sometimes it protrudes
further and displays two other smaller leaflets opposite to the former, but in the same plane margined
with cilia in like manner. The appearance is now
not unlike that of a flower of four unequal petals;:
from which resemblance, Linnaeus, who compared it
to a ringent labiate corolla, gave it the trivial name
ringens, by which it is still known. On each petal
we see a white line, probably a nervous thread,
running parallel with the margin, to which it is
connected by many radiating short lines.
" But the eye is involuntarily drawn from the petals
themselves of this living flower to the beauty of the
coursing cilia; these appear to chase each other
in ceaseless race along the margin, running down and
up the sinuous divisions of the petals; now relaxing,,
now refreshing, their speed. This progression of the
ciliary waves is now well understood ; but, while we
gaze upon them, we find it easy to forgive the error
of those who maintained that the teeth actually ran
around the margin of the stationary wheel.
" Below the large petals, on the ventral aspect, and
just above the level of the projecting antennae, is a
small circular disc or cavity, within the margin of
which a rapid rotation goes on. This little organ I

156

PONDS AND DITCHES.

can compare to nothing so well as to one of those
circular ventilators which we sometimes see in one of
the upper panes of a kitchen-window, running round
and round, for the cure of smoky chimneys."l Then
follows his excellent description of how he watched
and saw the animal build up its tube, how the pellets
were formed, and how they were deposited one by
one, as they were made on the upper portion of the
tube. Thus a " home without hands " is constructed
in a most marvellous manner by a diminutive creature supposed to occupy a place very low indeed, as
compared with the bird and the beaver, in the scale
of creation.
Like the Stephanoceros and the Floscule, this
little architect must also be sought on the submerged
leaves and stems of aquatic plants, such as the water
milfoil. If one or two are found the search should
be continued at once, for, as they are gregarious,
many more will doubtless follow. Gosse states that
he has found as many as sixty or seventy upon a
single leaf.
From individuals who live singly and separately
we pass to others flourishing in communities, of
which two examples must suffice. One formerly to
be found in great quantity in little ponds on Hampstead-heath, is the Conochilus.2 The clusters are
distinctly visible rolling slowly through the water,
now rising, now falling, not by any sudden jerking,
but gradually and steadily like that of a large body
impelled by a combination of small forces. The
1

"Tenby," p. 313

2

Conochilus volvox.

ROTIFERS.

157

groups (not exceeding i~3oth of an inch in diameter)
may consist of fifty or sixty individuals attached
together by the extremity of the slender foot to a
common centre, from which they radiate in all
directions, with the heads outwards. Each indi-

CONOCHILUS VOLVOX.

vidual is bell-shaped, and resembles a wine-glass,
without its expanded foot. The disk is large, and
of two semicircular portions, around which the cilia
play in such active motion that the eye distinguishes
no break in the circle.
" When a cluster is taken out of the phial in which
it is swimming about, and put into the live box, for
examination under the microscope, the number of
animals lying over each other, if it be populous, is
confusing. The numerous feet radiating from the
centre like the spokes of a glassy wheel, and the
multitude of crystal bells around the circumference,

158

PONDS AND DITCHES.

each surrounded by its crown of rapidly rotating and
strongly-marked cilia are almost distracting. Some
display the front, some the side; some turn themselves so as to present to the eye a transverse view of
the crown, others are almost vertical; it is only in
the latter, when the eye looks down upon the disc,
that the divided structure can be seen. Some are
continually shrinking up by forcible contractions of
the foot, and some are vomiting forth the flattened
pale-yellow eggs which are ready in the ovary. This
is, indeed, the first thing done as soon as a cluster is
put into the live box; the animals being probably
excited by being caught and moved from vessel to
vessel. Many eggs are presently seen, forcibly expelled from different individuals, and whirling about
in front of the animals."1
After an hour or two of confinement in the livebox the animals will be seen to separate, and the
communities break up. Each individual now floats
about on its own account, with the foot shrunk up
to the dimensions of a small nipple, and this end
generally thrust foremost. This dissolution is but
the prelude to an early death, the motions grow
fainter and fainter until they cease altogether, and
nothing is left but a yellow indistinct spot to
represent the once-vivacious Conochilus.
The other composite Rotifer is Lacinularicfi which
is much less common, but sometimes to be found in
numbers living amongst the Hornwort3 in ponds and
1
2

Gosse, " Contributions to the Rotiferce"
3
Lacinularia socialis.
Ctratophyllum.

ROTIFERS.

159

streams, with a preference for the latter. The clusters
are much larger than those of Conochilus^ being as
much as one-fifth of an inch in diameter. The individual animals have an elongated conical form, with
the wide extremity outwards, and the narrow blunt
•end attached to the common centre. The outer
extremity is terminated by a horse-shoe-shaped wheelorgan, or ciliated disc. When the animals are contracted and at rest, the disc is drawn in, and they
have at that time a more pear-shaped appearance.
There is one readily-appreciated difference between
the habits of Lacinularia and Conochilus, that whereas
the colonies of the latter usually float about freely in
the water, those of the former, except in young
colonies, are attached to aquatic plants. Unfortunately, confinement seems to be fatal to both, for of
the latter Ehrenberg says :—" In vessels of water they
rarely support themselves eight days ; they die and fall
to the bottom, even if plants be growing with them."
The anatomy and physiology of the Lacinularia
were closely investigated by Professor Huxley some
quarter of a century ago, and the results are given
in a most exhaustive paper on the subject, to
which those desirous of more explicit information are
referred.1
From the fixed and the community Rotifers we
must now pass to the free and independent individuals,
many of which are common in the localities within
our jurisdiction. We shall not feel bound to restrict
ourselves to any scientific order in their enumeration,
1

"Transactions, Microscopical Society," vol. i. (1853), p. 1.

i6o

PONDS AND DITCHES.

but mention a few as examples of the rest. It would
extend this chapter to disproportionate limits were we
to attempt to describe all the Rotifers which may be
found in still waters. Unfortunately there are no
popular names by which these little creatures are
known, so that we must be content with adopting the
generic name.
The Eosphora1 is a sprightly little species found in
tiny pools on heaths and commons,
as, for instance, on Hampstead Heath.
Its body is cylindrical, about one hundredth of an inch in length, and a
diameter of about one-third its length.
Its two-toed foot is short, and of
course occupies the lower end of the
body, whilst the variable head is at
the other. They will live and increase
if placed in a little bottle of water,
together with a few leaves of duckweed, some conferv, or other aquatic
plants, and left uncorked in full daylight, but protected from the rays of
the sun. In this condition they will
EOSPHORA.
play about, darting through the water
or scattering the sediment at the
bottom, rotating slowly as they go. Small as they are
their movements may be watched with a pocket lens,
if the fingers are placed on the opposite side so as to
form a kind of dark background for the objects.
When the animal is feeding, it rests upon its two-toed
Eosphora aurita.

ROTIFERS.

161

foot, the body is thrown forwards horizontally, and
the front of the head is so oblique as to be brought
almost as a flat surface into contact with the ground.
Suddenly the animal ceases feeding, rears itself on
its toes until it stands nearly erect, balances for a
moment, then evolves from each side of its head, by
a kind of turning inside out, a remarkable ear-like
process, clothed with strong cilia. The action of these
form vigorous circular vortices, of which the ear-like
expansions are the centres, and in the same instant
the animal shoots forward on its even course, revolving
slowly as it goes.
Of Notommata there are several species, and two
of these are to be found living within the rolling
spheres of Volvox. One species persistently, the
other occasionally, being thus parasitic. On examining
the volvox even with a pocket lens the discoloured
spots may be seen which indicate the presence of
Notommata,1 which lives and floats about inside the
transparent sphere with as much ease and comfort as
a gold-fish in a glass globe. Sometimes Mr. Gosse
remarks that he has seen as many as four individuals
inside one volvox, each pursuing its own vocation
regardless of the others. Of the other species of
Notommata, one is sometimes found in water-butts,
another in water pools in bogs, and another in old
infusions.
The Synchceta is compared to a boy's peg-top, with
the iron toe driven in by constant " pegging" until
only the point is visible. This point represents the
1

Notommata /arasita.
M

162

PONDS AND DITCHES.

minute foot of the animal, with its tiny toes. " Now
and then the creature rests on these united toe-tips,
and rotates for several minutes as if to maintain its
character as a spinning top, then away it shoots, and
glides swiftly and giddily through the clear water by
the hour together without repose, its enormous ciliary
apparatus giving it great power of motion. The
rounded front appears to
be beset with cilia, but it
forms a sort of indented
crest or forehead, on which
two antennae are seated, as
well as some pairs of curious stout branched bristles,
which then descend on
each side in the form of
two hanging lobes or ears,
richly clothed with vibrating
cilia, and are powerful auxiliaries to swimming. As it
swims it is almost continuSYNCHiETA.
ally contracting the enormous head with a sort of spasmodic twitching, which
brings the ear-lobes momentarily to point forward, and
alternately, and almost as quickly recovering itself.
The brilliant transparency of its tissues is highly
characteristic of the tribe, and combined with their
elegant form and sprightly motions, makes them rank
among the most charming representatives of the class." 1
1

Gosse on Flexible Creepers, "Popular Science Review,'"
vol. ii., p. 4^4-

ROTIFERS.

163

Two species are found usually amongst Conferva*
but always in clear sparkling water, and one is only
found in salt water.
The Pitcher Rotifers 1 are a numerous and very
characteristic family,
with a short, broad,
urn-shaped body, and
a long flexible foot.
Some are absolutely
marine, whilst others
are
inhabitants
of
ponds and ditches.
Their principal feature
is the pitcher-shaped
lorica, or shield of the
body, which is notched
at the top into several
projections. The lorica
has some resemblance
to the shell of a tortoise, open at both
ends; from the top an
elegant wreath of cilia
is protruded, and some
slender spines. It has
a capacious stomach,
P I T C H E R R O T I F E R Or
and an " aldermanic
BRACHIONUS.
allowance of gizzard."
When the prey is caught within the circle of the
vortex caused by the action of the strong cilia, it is
Brachionus.
M 2

164

PONDS AND DITCHES.

speedily carried down to the gizzard, and occasionally
if found too large or unmanageable, is cast out again.
" A description of this animal would be very incomplete if it omitted that important organ the tail (or
foot) which in this family reaches the highest point of
development. It is a powerful muscular organ, of
great size in proportion to the animal, capable of
complete retraction within the lorica, and of being
everted wholly, or partially, at will. It terminates in
two short conical toes, protruded from a tube-like
sheath, and capable of adhering firmly even to a
substance so slippery as glass. This organ may be
observed to indicate a variety of emotions, if we can
ascribe such feelings to a Rotifer, and it answers many
purposes. Now we see it cautiously thrust forth, and
turned this way and that, exploring like an elephant's
trunk, and almost as flexible. Now it seizes firm
hold of some substance, and anchors its proprietor
hard and fast. A few moments afterwards it lashes
out right and left with fury, like the tail of a cat in a
passion. Then again it will be retracted, and a
casual observer might not imagine the Brachionus to
be furnished with such a terminal implement." 1 It is
not unusual to see one of these Rotifers sailing about
in ease and comfort with two or three eggs attached
to the lower surface of the body near the foot.
Perhaps no Rotifer has been more widely or extensively known than that which is figured in older
microscopical books as the " Wheel-animalcule." It
is sometimes called the " Common Rotifer " 3 and is
1

Slack's "Pond Life," p. 125.

2

Rotifer vulgaris.

ROTIFERS.

165

perhaps the commonest of all the species. The elongated body is terminated in its upper portion by a
proboscis ciliated at the end—on which
the two eyes are placed, on either side
is the rounded lobe of the rotary organ,
or " wheels," as they were called when
their structure was almost unknown.
The lower extremity terminates in a
foot with two toes, and this foot is in
reality telescopic, one tube within
another, so that it may be shortened
or elongated in the same way as a
telescope is drawn out or pushed in.
This little creature is found in all kinds
of localities, in fresh water, even in
gutters around the roofs of houses,
besides ponds and ditches, and little
puddles on heaths.
COMMON
This Rotifer sometimes remains atROTIFER.
tached whilst being examined under the
microscope, by fixing its foot to some fragment of
a water plant; at other times it is very restless, and
keeps moving about in search of an eligible site.
When it is possessed with this roving disposition it will be seen that it travels as a caterpillar travels, by looping; just above the foot its
attachment is accomplished by means of a small
round disc resembling a sucker, and the proboscis at
the other end also attaches itself in the same manner,
forming a kind of temporary sucker. Extending itself
in full length, it waves about, and at last attaches its
proboscis, then it draws up its nether extremity nearly

166

PONDS AND DITCHES.

to the head. The little discoid sucker is seen attached
to the glass, and the frontal extremity is thrust forward
again to the extreme length of its attenuated body,
and in this manner it soon makes rapid progress out
of sight. In these movements it will also be observed
how, in contracting itself, the Rotifer slides one joint
into another, like shutting up a telescope. Of course
whilst moving about in this restless manner, the
4(
wheels " are not in operation.
It will be as well to caution the inexperienced
observer of these organisms, that every Rotifer
which may to him appear to be of this species
may in reality be very different. It is by no means
unusual to meet with another bearing a considerable
family likeness to it in the same situations, but which
at a glance is seen to possess a most decidedly roseate
hue. The rosy colour, however, is only a minor
difference, for, as soon as the creature has become
sufficiently quiet to undergo examination, the two
red eye-spots, which, in the common Rotifer are seated
on the proboscis, are in this Rotifer seated much lower
down, upon what might be termed the breast, and
wider apart from each other. This feature, combined
with the rosy colour, will indicate the " Rosy Philodina." 1 The last time we saw this Rotifer, less than a
week before penning these lines, it was on a minute
fragment of a Choetophora (Fresh-water Algae) that had
been placed under the microscope for the purpose of
determination, and, behold, no less than five individuals of this species of Rotifer made their appearance
1

Philodina roseola.

ROTIFERS.

167

at the same instant. What an immense number must
have been present on that little tuft of green water
weed! The bright rosy colour, sometimes much
brighter than at others, adds considerably to the
beauty of this animal. It moves through the water,
when not too closely confined, by a swimming rather
than a crawling movement; but when cramped for
room, by being compressed, it has a gliding motion.
We have always found it entangled amongst the tufts
of some one of the filamentous Algae.
Apropos of the Rotifers which linger amongst
Confervae, there is a pretty little fellow, clad in a
carapace, or transparent shield, often found in such
situations.1 It is a small Rotifer, but a very active
one, swimming about freely. The shield, or transparent covering, is oval, pointed behind, and the foot
is rather long with two toes, or divisions. The eyes
are rather distant apart but quite distinct. When
quiet, amongst the debris of decaying vegetation, it
may be seen perched on its foot, with its body bent
forwards at right-angles, and a curious hook projecting
from the front of its upper extremity. This hook is
curved downwards, and has the shape of a miniature
sickle. As the Rotifer poises itself on its foot, bending
forwards, bowing, and bobbing up and down, it
occasionally brings down the point of the hook to
the Algae amongst which it roams, and apparently
scratches them, as a hen scratches in a farm-yard.
Whether such a use is one of the functions of the
.hook, we cannot tell. It is perfectly clear and
1

Metopedia acuminata.

168-

PONDS AND DITCHES.

colourless. But we have several times seen a rather
larger, and it seems to be a different, species, with
a slight rosy colour. This has the carapace at the
upper end hollowed out, so that the two angles project like short spines, and there is no frontal hook.
The toes are shorter than in the other species, but
its habits and mode of life seem to be very similar.
Some of the species have a ridge, like a keel, down
the back, but in this one the back of the carapace is
only gently convex.
It is much to be wished that some one would
discover a method whereby Rotifers can be put to
instant death, with all their organs fully extended,
so that they may be mounted as permanent objects
for the microscope. There are some minute creatures to whom a drop or two of sweet spirits of
nitre supplies a "happy dispatch," for they immediately
die with all their organs expanded, and in this state
can be " mounted " and always examined. But, up
to the present, no one has devised such a method
applicable to the wheel-bearers. As they die they
contract, and become beyond power of recognition,,
except those furnished with a shield, and the empty
" c a s t s " of these are as good as the dead animals.
The most perfect " mounting " will never equal living
animals for the purpose of study, but it must be
remembered that living animals are not always to b e
found just when they are wanted. And, for scientific
purposes, a good method of preserving these and
similar animals is very requisite. It may be a very
rare, or unique individual which presents itself. A
few hours and it is dead, and past recognition.

ROTIFERS.

169

Nothing is left but hasty and imperfect sketches,
and, as far as the interests of science are concerned,
the creature might as well never have been seen.
On the other hand, if some good mode of preservation were discovered, such an object might find
a place in a national museum, to be referred to and
consulted.
It very often happens that a happy
thought, or a fortunate discovery, originates with those who are by no means
adepts in science; and it is quite as
probable that those who may read these
pages, and discover that such a " want"
is recognised, might contribute to its
satisfaction, as those who have long felt
the want, but never found the remedy.
We commend it therefore to the consideration of those who have the will,
and the leisure, and the aptitude, for
investigation in microscopical manipulation.
The "Whip-tail" 1 is in its entire
length not more than one-seventieth of
an inch, of which fully one-half is occupied by the long slender foot. It has
only one eye-spot. This creature is to
be found amongst Confervas swimming
slowly, and in a stiff and awkward man- WHIP-TAIL.
ner. When stationary the foot is jerked
backwards and forwards, and this, combined with its

^fe

1

Mastigoccrca carina'a.

170

PONDS AND DITCHES.

slender form, has procured for it the name of "Whiptail." It will always be found productive of satisfactory results to examine closely amongst Confervas
for wheel-bearers. Even during February we have
found no less than four different species of wheelbearers amongst a few Confervae from a pool on
Hampstead Heath.
The Skeleton Wheel-bearer,1 is another of the rarer

SKELETON

WHEEL-BEARER.

species, and is found amongst the Hornwort.2 There
are, indeed, two species, one with a shorter body
and longer toes 3 than the one figured, and found also
amongst duckweed. The prominent feature in the
1
2

Dinocharis pocillum.
Dinocharis tetractis.

3

Ccratophyllum.

ROTIFERS.

171

species figured, is, that it has two long spines at the
base of the foot, which is terminated by three toes,
of which one is shorter and rudimentary.
A curious Wheel-bearer,1 with somewhat of a top
shape, but blunted at the lower extremity, is to be
found amongst Confervae. The chief interest, however, attaches to the presence of six long narrow
blades, like fins, which project from each side, and are

moveable. These fins or wings give the little creature
a most formidable appearance. No Wheel-bearer is
so subject to parasites as this, and it is seldom seen
without some of these adhering to its body, as shown
in the figure.
It will afford great assistance to the young student
1

Polyarthra platyptera.

172

PONDS AND DITCHES.

of the Wheel-bearers to observe that some of them,
as the Common Wheel-bearer, have flexible bodies,
which retract or lengthen, and assume varied shapes ;
whilst others, such as the foregoing are enclosed in a
lorica or shield, like a tortoise, and, consequently,
are not so polymorphous. The presence or absence
of a shield will assist in determining their names.
The revival of Wheel-bearers after desiccation has
long been known, and cited as one of the mysteries
of low-life. Doyere, a French naturalist, says that
they will revive, that is, pass from a motionless state
to one of motion after having been exposed to a
cold of 20 0 below freezing point, or to a heat of
113 0 Fahr.; that they preserve the property of reviving
in dry sand up to a temperature of 1590 Fahr., but
that they lose this property and remain immovable if
warmed in moist sand to 131° Fahr. H e also says
that he has seen them slowly revive after being dried
without sand. Ehrenberg has given a most complete
history of all the observations instituted on the socalled revivification of Rotifers. H e believes that
notwithstanding all the means of desiccation employed,
life still remains in the apparently dead animal. H e
contests the hypothesis of latent life, for death, he
says, is not life in a torpid state, but the absence of
life. Fontana mentions that he succeeded in restoring to animation, after two hours' immersion in a
drop of water, a Wheel-animalcule which had lain in
a dried and motionless condition for the space of
two years and a half.1
1

Humboldt's " Views of Nature," p. 240.

ROTIFERS.

!73

There are three kinds of minute creatures capable
of enduring a great amount of dryness for a long
period of time, resuming activity after the application
of moisture, these are the Rotifers, or Wheel-bearers,
the minute worm-like creatures called Nematoids, of
which the wTheat Vibrios are an example; and the
Tardigrades, or Water-bears, little creatures bearing a
relationship to spiders, and mites. There are others,
such as some of the Entomostraca, which exhibit
similar phenomena to a limited extent.
We might extend this enumeration considerably,
but enough has been done to show the character of
the different groups of these interesting little creatures,
and we hope enough also to interest some of our
readers in their habits and economy. We only regret
that the few pages which we have been able to devote
to over one hundred and twenty different species of
British aquatic animals of this type do not enable
us to enter into any details of their minute structure,
and of their modes of increase and dissemination,
and allow us to give but slight glimpses of their
habits of life.

*74

PONDS AND DITCHES.

CHAPTER XL
LEECHES

AND

WORMS.

WE must confess that there is some excuse for the
great dislike which most people evince for such
crawling creatures as leeches and worms. There are
very few of the terrestrial or fluviatile species which
are at all comely, none which we can truthfully declare to be beautiful. And yet, even leeches and worms
are necessary in the economy of nature; they have
their appointed places to fill and duties to perform,
and for these their form and structure are so admirably adapted that we could conceive of no
improvement. Undoubtedly the most attractive of
Annelids are marine, but that would be no excuse
for our omission of fresh-water species.
Leeches are, of course, worms of a certain character, that is, they belong to that large class known
as Annelids, and popularly as Worms. Some persons,
suppose that all leeches belong to one of two species,
the one named the Horseleech, and the other the
Medicinal Leech. This, however, is a popular error,
and not the only one associated wTith leeches. Certain leech-like animals which attach themselves to
living fish do not come within our cognizance.

LEECHES AND WORMS.

175

1

The Horseleech is found in lakes and ponds, attaining a length of 4 inches, greenish-black on the
upper, and yellowish-green on the lower surface, at
least this is one of the suctorial leeches to which the
name of horseleech is applied. There is also another
leech, 2 which is not suctorial, as the rudimentary
condition of the jaws disables it for piercing the skin
of animals. It is doubtless this which most commonly goes by the name of horseleech. It also is
about 4 inches in length, and similar in colour to
the above. The true medicinal leech 3 is from 4
to 7 inches in length, greenish-olive, or very dark
green above, with six broken yellow bands along the
back. Of these three kinds of leeches the first and
last are suctorial, and the intermediate one is not.
The medicinal leech was formerly common in this
country, but it is now rare, especially in the south.
Traditions of leech-gathering lingered till recently in
the north, else wherefore those lines of Wordsworth:—
" He told, that to these waters he had come
To gather leeches, being old and poor ;
Employment hazardous and wearisome !
And he had many hardships to endure :
Housing, with God's good help, by choice or chance;
And in this way he gained an honest maintenance."

That they were becoming scarce, even at the time
this poem was written, is evident from a succeeding
verse :—
" He said, that, gathering leeches, far and wide
He travelled ; stirring thus about his feet
The waters of the pools where they abide.
1

Hcvmopsis sanguisuga.

2

Aulostomagulo.

3

Hirudo mcdicinalis.

176

PONDS AND DITCHES.
' Once I could meet with them on every side ;
But they have dwindled long by slow decay ;
Yet still I persevere, and find them where I may.' "

The suctorial leech sucks the blood willingly of
all the vertebrate animals; to accomplish which it
attaches itself first by means of the sucker at its
opposite extremity, and a suitable spot being selected
it cuts through the skin. This is accomplished by
means of its three teeth, embedded in a strong circle
•of muscular fibre. Each tooth is somewhat semicircular, with its free
margin toothed, resembling a minute
semicircular saw. If
a leech be carefully
watched, it will be
seen that a sawing
motion is given to
each tooth by the
MOUTH OF LEECH (enlarged).

strong muscles, and

hence that the trixadiate wound of a leech consists of three minute
saw-cuts.
T h e rest is known to many experimentally. There is, however, one fact about leeches
not generally known, that they possess ten eyes, arranged in a curved line.
The Common Horseleech (Aulostomd) is a cruel
and greedy worm, feeding on earthworms, grubs,
snails, and other leeches, but although carnivorous,
it has only three small cartilaginous teeth, and cannot
inflict a wound like the true leech, neither is it a
suctorial worm. Stories are numerous in country

LEECHES AND WORMS.

177

districts of the dangerous character of the horseleech,
such as "nine horseleeches will suck a horse to
death," &c, but, as observation and examination will
prove that the horseleech could neither wound a
horse nor suck it, all such stories must be fallacious.
Dalyell says of it,—" This is an active, bold, and
clever animal, frequently crawling out of the water,
and apparently always ready to quit its vessel. None
of the tribe surpass it in voracity. Few animal substances are rejected. All kinds of fish, dead or alive,
seem acceptable. Penetrating the cavity of the larger
fresh-water shells, the horseleech takes up a permanent dwelling there until emptying them of their
contents, should it be able. Several of this species
and another having been collected from the same
place, one of the latter, half-swallowed by a horseleech scarcely double its size, was struggling for
liberty. But its ferocious enemy, adhering firmly by
the sucker, and undulating its body in the water, as
if to aid deglutition, occupied three hours in finishing its task, when it appeared much distended by so
copious a repast. Another attempted to devour a
dead leech of a different kind, absorbing the smaller
extremity here, as the former did with its living companion, but the latter proved too large for its gullet.
Considering the strength of the prey, indeed, and the
adhesion, it appears a hardy effort of leeches to devour
each other, unless under great disparity of size."
The Eight-eyed Leech1 is also one of the non-suctorial leeches found in stagnant or slow-running water,
1

Ncphdis octoculata.
N

JjS

PONDS AND DITCHES.

but it is very small, not exceeding an inch and a half
in length, and of a reddish-brown colour, with variable markings. It does not appear to be at all
common. It is a very active leech, swimming in the
water by an undulatory or serpentine motion of the
body. " The structure of the mouth unfits it for eating solid food, or biting through the skin."
The residue of our leeches belong to a different
tribe ; they are small and usually very transparent,
there are certainly six, and perhaps nearly double that
number, of British species, inhabiting ponds, dwelling
amongst the aquatic plants, but incapable of swimming, and not voluntarily leaving the water. Most
of them have but six eyes, some of them have apparently but two, whilst one has eight. The Chequered
Leech1 is perhaps the best known, and that appears
to be a northern species. As it is with the rest of
the Annelids so is it with the leeches;—so few persons
have taken any interest in them that it is not truly
known what species are to be found in the British
Isles, or the extent of their distribution; and, for our
knowledge of their structure, habits, and economy,
we are mainly indebted to Continental writers.
There is another small group of aquatic worms
called Naides, which are very vivacious in their
habits, creeping about amongst aquatic plants, and
can even swim. They are supposed to live upon
the smaller members of the family of water-fleas, but
there is not much of special interest attached to
them, calling for more than a brief passing notice.
1

Glossiphonia tessellata.

LEECHES AND WORMS.

179

There are to be found in our ponds and ditches a
great number of little broad, flattened worms, with
some resemblance to " flukes," which are covered with
cilia, and lead such a retired life that very little is
known about them. The name of Planarian Worms
is sometimes heard, but very few, even of those who
are always in search of objects for the microscope,
have the slightest idea of their character, structure,
or habits. These obscure animals are small, the
largest of the pond species scarcely exceeding
half-an-inch; they are also unattractive, and, worst
of all, there is no book in the English language
to assist in their study. They are so soft and
gelatinous in their nature, that when dead the
majority of them decompose and become a watery
mass in the course of one or two minutes. The
commonest little black fresh-water Planarian1 belongs
to a genus characterized by the possession of many
eyes, but species of true Planaria will be found abundantly in company with it. Duges describes the
wonderful power of reparation of injuries which they
possess. " By slitting them with scissors individuals
may be produced with two heads or two tails, and
otherwise modified." In one species certain organs
have been described as probable spinnarets, like
those of a spider, but there is some uncertainty about
them. Dalyell, in one of his works, notices two or
three species of Planarians as apparently spinning,
and hanging by the threads. When even amongst
professed naturalists so very little is known about
1

Polycelis nigra.
N 2

i8o

PONDS AND DITCHES.

them we cannot be expected to do more than thus
indicate their existence. 1
The mud of ponds and ditches, as well as that of
rivers, is often to be seen literally covered with little
protruding red worms from i inch to i j inch in length,
with half the body immersed in the mud, and the
other half exposed. They possess such facilities for
the reproduction of the species that they increase with
great rapidity, and may often be seen in such numbers
as to cause patches of red on the surface of the mud
in which they burrow. When disturbed they withdraw
their bodies into the mud, and with them the red
patches instantly disappear. This little creature is the
Summerworm, or Red River-worm 2 and belongs to the
same family as the earthworm, but has much more
interest because of its delicate uncoloured skin,
through which, as through glass, the whole of its
internal economy may be seen and studied. The
red appearance of these creatures is due to the bloodvessels seen through the transparent skin; and here
we have an open book, which the inquisitive may read,
and learn all the mysteries in the life of a little worm,
with its two hearts, its large liver, its blood-vessels,
its nervous centres, and indeed its whole nervous and
circulatory system, even to the discovery of its parasite,
a little Infusorian which dwells in its interior, and
seems to enjoy itself within a world entirely its own.
The annuli or rings can be seen and counted under a
1

Ray Lankester, on Planarian Worms, in " Popular Science
Review," vol. vi., p. 388.
2
Tubifexrividoriim.
See also "Popular Science Review,"
vol. ii., p. 10.

LEECHES AND WORMS.

181

lens, and by the same means the two lateral rows of
bristles may be distinguished. Notwithstanding the
general dislike which most persons feel towards all
such creeping animals as snakes and worms, it is well
to suppress such a feeling for a while in favour of
this harmless little " red-worm," and learn some of the
many lessons it can so readily teach.
There are to be found in localities and in situations
which are variable, certain small, slender, worm-like
creatures to which the name of Nematoids has been
applied. Some of these come within our jurisdiction
and therefore demand some notice. Three Nematoids
may be named, with which most persons are familiar,
and these will serve as excellent types of the kind of
creatures concerning which we are writing. These
three are called, the Vinegar-Eel, known to microscopists as developed under certain conditions in
vinegar ; the Paste-Eel, which any one may soon rear
for themselves from stale paste; and those minute eellike bodies called Vibrios found in wheat suffering
from the disease called " Pepper-corn" or " Earcockle. " These are all examples of Nematoids. They
are minute, eel-like, or worm-like creatures, the structure and anatomy of which may be studied in special
memoirs devoted to the subject. In size they vary
from one-seventieth of an inch to three-quarters of an
inch in length; and the sort of places in which
they are found are thus summarised by Dr. Bastian :—
" Beginning with the land and fresh-water species, I
have found them in all the specimens of soil examined,
in moss, in various species of lichens, about the roots
of fungi, also in the roots of grasses, and between the

l82

PONDS AND DITCHES.

sheaths of their leaves, amongst the mud of ponds
and rivers, on the fresh-water Algae, amidst decaying
liverworts and mosses, and on submerged aquatic
plants." l
They differ very much in the amount of activity
which they exhibit, some being slow and tardy, whilst
others are quite the reverse. The mode of locomotion
is the same in all; it consists chiefly in those eel-like
undulations which obtained for the well-known species
the name of "eels." At times they
climb and twine amongst the Algae and
other water plants, which they frequent,
in a serpentine manner, or anchor themselves firmly by means of a sucker at
the tail, with which all the species are
provided; on such occasions they sway
themselves backwards and forwards for
a while, and then dart off with great
celerity.
The free Nematoids—for there are
also parasitic Nematoids, with which
we have nothing to do—are chiefly
NEMATOID.
vegetable feeders, taking a small quantity of food at a time. Their power
of repairing injuries seems but slight, for when
accidentally divided they will linger for about a
week, during which time both parts will continue
to move about, and then die. On the other hand
the tenacity of life in some of the species is most
1
Bastian, "Anatomy and Physiology of the Nematoids,JV
*' Philosophical Transactions," 1866.

LEECHES AND WORMS.

183

remarkable, of which the Vibrios of wheat is also
a familiar example.
Thus Baker ascertained that
some of the animals contained in diseased wheat
given to him by Needham in 1744 still possessed
the power of resuming all their vital manifestations in 17 71, after immersion for a time in water.
The results of one experiment conducted in France
will illustrate the power possessed by Rotifers, Tardigrades, and Nematoids of reviving after desiccation,
sufficient, it would have been thought, to dry all
vitality out of them. " Portions of moss which had
remained sixty-seven days in a cabinet, were submitted
for two days to the influence of dry air, and during
fifty-one days to the action of a vacuum. The mosses
then became so completely dried that, after four days
of exposure to the double influence of a vacuum and
sulphuric acid, they underwent not the slightest diminution in weight, and yet, after twenty-four hours of
simple moistening with water, the Rotifers, the Sloths,
and the Nematoids had completely regained their
vitality."
There is one species which may be alluded to,
found on the mud of ponds, which has the habit of
coiling itself into a circle when touched. 1 Others
occur also on the mud of freshwater pools, and several
species inhabit the water milfoil, which harbours so
many aquatic animals. The general appearance of
all is very similar, and it is doubtful whether any but
the scientific will take much interest in their distinctions.
Only a worm ! Why trouble more about the nasty
1

Trilobus pellncidiis.

184

PONDS AND DITCHES.

crawling things ? Only a worm ! Such an ejaculation,
and with an emphasis too, has been heard once and
again. Would that we could whisper in the ear of
him who next is prepared to utter it a word of caution. Was it not He who made the world, He who
created Man, that also called into being, for some
good purpose of His own, the poor, despised worm ?

PONDS AND DITCHES.

185

CHAPTER XII.
SPIDERS, MITES, AND WATER-BEARS.

IT is very usual for ordinary people, who lay no
claim to be considered scientific, to speak of spiders and mites as " insects," and no great crime is
committed by such an act, although learned professors might be horrified. The fact is, that although
formerly included with insects, the advance of
science has pushed them out of the class of insects
and sent them into the neighbourhood of the crustaceans. So that it is no longer accurate to speak
or write of spiders and mites as insects, under pain
of being regarded as an " ignoramus."
Spiders and mites are very numerous, the latter
especially so, and yet very few of them are aquatic.
In this country it is usual to speak of the waterspider, which assumes that we have but one species
with such habits; yet, Mr. Blackwell, who is one of
our best authorities on such subjects, says that
" several of the semi-aquatic species belonging to two
genera,1 run fearlessly on the surface of the water,
and even descend spontaneously beneath it, the
time during which they can respire when immersed
depending upon the supply of air confined by the
Lycosa and Dolomedes.

i86

PONDS AND DITCHES.

circumambient liquid amongst the hairs with which
they are clothed." 1
The Argonaut, or Argyroneta, 2 was at one time
common enough in ditches, and, for a period enjoyed a dangerous reputation, since it is large enough
to permit its movements being watched with facility.
Its interesting habits are well known, and have led
to their being often kept as pets. Indeed, a few
years ago it became so much
a fashion that, like sea-anemones during the rage for
aquaria, they have become
scarce, even in localities such
as the ditches about Oxford
or Cambridge, which are most
adapted for them, and where
they were formerly plentiful,
they having been caught and
sent up to London in quantities for sale by dealers in
objects of natural history.
WATER-SPIDER.
They can live indifferently,
either on dry land or under
water, but practically they spend the greater portion
of their time in the latter. Their eggs are moored
in silken cocoons to the stems of aquatic plants,
under a dome-shaped cell, which is filled with
air like a diving-bell, by the spider carrying down
successive globules of air between its legs, which it
liberates under the dome until it is filled, and the
1

"British Spiders," p. 16.

2

Argyroneta aquatica.

SPIDERS, MITES, AND WATER-BEARS.

187

young are hatched there. The spider on its way
through the water never gets wet. It is clothed with
hair, which, combined with its respiratory organs,
enables it to surround itself with a halo or enveloping
bubble of air in which it moves about protected from
wet, and well supplied with air to breathe. It can
be drowned for want of air, however, as well as any
other animal—Mr. Blackwell mentions such a case.
" One of these creatures which had been got in the
fens of Cambridgeshire was given to a friend. On
being placed in a large goblet more than half filled
with water, it speedily formed its dome-shaped cell
beneath the surface, attaching it to the side of the
glass by means of numerous silken lines, and being
well supplied with insects, it lived in this state of
captivity till the commencement of winter, when, on
the temperature of the room in which it was kept
becoming much reduced it entered the cell, and
remained there in a state of torpidity with its head
downwards. A gentleman on a visit at the house,
whose curiosity to examine the spider minutely in
its hybernaculum was greater than his prudence, inclined the glass so much that the air escaped from
the cell, the water flowed in, and before information
of the circumstance was given the dormant spider
had perished. The spider feeds upon any insects it
can catch, whether land or water species ; and whether
she gets them on shore or not she generally carries
them into her cell to suck their juices there." 1
The Piratic Spider 3 is less than 4-ioths of an inch
1

Murray's " Economic Entomology," p. 73.

2

Lycosapiratica.

188

PONDS AND DITCHES.

in length, of a brown colour, with white spots, and
frequents the margins of pools. It runs rapidly on
the surface of water, even when carrying its cocoon,
and " frequently takes refuge from danger beneath
the surface of that liquid, concealing itself among
the leaves of aquatic plants." It can carry down
with it sufficient air to remain immersed for a considerable time.
Another, and one of the largest of British spiders, 1
with legs upwards of an inch long, is of frequent
occurrence in the fens of Cambridgeshire, and, like
the foregoing, descends spontaneously beneath the
surface of the water. The body and abdomen are of
a reddish-brown colour, with a broad paler longitudinal band on each side. It is quite possible that
these are not the only spiders we have which will
take to the water, as the number of observers capable
of distinguishing the species are remarkably few.
Familiar objects to the pond-collector are the little
bright vermilion mites which swim about vigorously
amongst the water-plants.
Little bright red dots,
and to the naked eye they are scarcely more, float
about in the clear water, but never in numbers, only
two or three being seen at a time. Some there are, it is
true, which never swim at all, but are content to crawl
over the surface of the submerged vegetation. Under
a lens the little red dots are seen to resemble a spider
in shape, indeed, they are sometimes called "little red
water-spiders/' but the name of water-spider belongs
of right to the larger animals. These, which to the
Dolomedes fimbriatiis.

SPIDERS, MITES, AND WATER-BEARS.

189

naked eye seemed only red, are by enlargement found
to be marked with black dots or bands; and all are
not black, for some are yellow, and some also green.
It is well known amongst naturalists that the
water-mites have in their earlier stages fewer legs
than the mature individuals.
In some of the
genera they are said to have but three at first;
it is common to see them with only six; when
mature they should have eight. The young ones
are hatched from eggs which are
deposited on the stems of water
plants. It is a curious fact that
after being hatched the young in
some instances, before they are
capable of swimming, attach themselves to the bodies of water in- WATER-MITE
sects, such as the bugs and beetles, (Diplodontus).
and are carried about by them until
they are able to move about freely on their own
account.
Although some of these little animals were observed
and figured in this country some years ago, no one
has made their study a special subject, and consequently we are far behind Continental naturalists in
our knowledge, not only of the water-mites, but of
all the Acari. 1 Of course, the subject is beset with
difficulties, and so is every subject, for there is no
royal road to knowledge; but we have observed
young men, who commenced enthusiastically with
1
Figures and descriptions of the different genera of watermites are given in Murray's "Economic Entomology" {Aptera).

190

PONDS AND DITCHES.

water-mites twenty years ago, subside gradually until
at length the objects in question were never mentioned.
There is not only considerable difference between
the appearance of the young mites and the mature
ones, but also between the male and female of the
mature animal; this increases the difficulty of recognition, so that we cannot be said to know any one
species until acquainted with its entire life-history.
The number of mites which inhabit
a variety of places, terrestrial and
aquatic, in this country must be verygreat, since some characteristic form
or other is sure to be met with,
even under the most unexpected
conditions. It might almost be
(£y/ais). doubted if a locality could be found
where a mite would not make itself
at home, parasitic, or non-parasitic, in fresh water
or salt, amongst food or poison, on animal substances or vegetable, single or in colonies, smooth
or hairy, with long legs or short ones, bodies round
or long, nearly square or triangular, white, black,
brown, red, yellow, or green. The difficulty would
rather be to name conditions and places in which
they could not thrive.
The Water-bears are curious, and in some respects
remarkable little creatures, second cousins to mites
and spiders, but with very little family likeness.
Some are found crawling over aquatic plants, and it
is with these that we are chiefly concerned; others
nestle amongst the tufts of moss on the roofs of

SPIDERS, MITES, AND WATER-BEARS.

191

houses where they pass through alternate periods of
great moisture and great dryness; others occur on
tufts of moss in damp situations. They are little
creatures with oblong bodies, furnished with eight
short feet armed with claws. Their usually sluggish
movements have originated the name of Tardigrades,
or slow-walkers, but they are more commonly known
as little Water-bears. We know but little of their
history, and this has been summarized by Mr. Slack.1
The figure was like that of a newborn puppy, or bear-cub; each of
the eight legs was provided with
four serviceable claws, there was no
tail, and the blunt head was susceptible of considerable alteration of
shape.
H e was grubbing about
among' some bits of decayed vegetation, and from the mass of green
matter in his stomach it was evident that he was not one of " t h e
starving poor." The movements of
the Water-bears, although slow,
evince a decided purpose and
WATER-BEAR.
ability to make all parts work together for a common object; and as might be expected from this fact, and also from the repetition of
distinct, although not articulated limbs, they are
provided with a nervous apparatus of considerable
development, in the shape of a chain of ganglia and
a brain, with connecting filaments. Like the spiders,
they cast their skins.
1

"Pond Life," p. 173.

192

PONDS AND DITCHES.

The Water-bears possess in common with the Rotifers the power of supporting protracted desiccation,
and of reviving on the application of moisture. Pritchard says that they can be revived after being put
into hot water at 1130 to 118° Fahr., but are destroyed
by immersion in boiling water. "They may be
gradually heated to 216°, 2500 and even 261°. It is
also by their capability of resuscitation after being
dried that they are able to sustain their vitality in
such localities as the roofs of houses, where at one
time they are subjected to great heat and excessive
drought, and at another are immersed in water." In
a memoir, written upon this very subject, Doyere, a
French naturalist, thus summarizes his experiments.
" Desiccation conducted in an ordinary temperature
might be open to many objections which are not perhaps wholly obviated by the employment of a vacuum,
but when we observe that the Tardigrades irrevocably
perish in a temperature of 1310 Fahr., if their tissues
are permeated with water, whereas they can, when
dried, support a temperature that may be estimated at
2480 Fahr., we are disposed to admit that the sole
condition required for animal revivification is the
perfect integrity of organic structure and continuity; "
and Humboldt, after comparing these phenomena with
the winter sleep of reptiles, adds, " the apparent revivification of the Rotifers, and of the silicious shelled
Infusoria, is only the renewal of long-enfeebled vital
functions—a condition of vitality never entirely extinguished, but merely revived by excitation."

PONDS AND DITCHES.

193

CHAPTER XIII.
WATER-FLEAS.

A LITTLE group of minute aquatic Crustaceans has
obtained the name of " Water-fleas ; " not that they
really are fleas, but because of their brisk, jerking
motions, almost like leaping in the water. Being
Crustaceans, they have a relationship to shrimps and
lobsters, agreeing with them also in being aquatic, but
differing considerably in size, the largest British species
not more than one-fifth of an inch in length. Their
scientific name is Dafihnia, first called Daphne,
probably because in classic story Daphne was a
daughter of the river Peneus, albeit the water-fleas
delight rather in stagnant, than running water, and
are rather the daughters of the horse-pond than the
river. They are only to be found in fresh water; some
preferring ditches in which there is much duckweed
floating on the surface, others delighting in ponds
where cattle come to drink. In such places they are
to be found in myriads, nearly all the year round, and
as they sometimes assume a red colour, they have
been said to have tinged the water with the hue of
blood. Swammerdam observed this fact two centuries
ago, and he says that he has seen them in such numbers at Vincennes as actually to give the water of a
horsepond the colour of blood. " I have," writes
o

194

PONDS AND DITCHES.

Dr. Baird, "frequently seen large patches of water in
different ponds assume a ruddy hue, like the red rust
of iron, or as if blood had been mixed with it, and
ascertained the cause to be an immense number of
Daphnia pulex. The myriads necessary to produce
this effect is really astonishing, and it is extremely
interesting to watch their motions. On a sunshiny
day, in a large pond, a streak of red, a foot broad,
and ten or twelve yards in length, will suddenly appear
in a particular spot, and this belt may be seen rapidly
changing its position, and in a very short time wheel
completely round the pond. Should the mass come
near enough the edge to allow7 the shadow of the
observer to fall upon them, or should a dark cloud
suddenly obscure the sun, the whole body immediately
disappear, rising to the surface again when they have
reached beyond the shadow, or as soon as the cloud
has passed over." 1
The body of the Water-flea is composed of two
portions, the smaller forms the head, the larger consists of the thorax and abdomen, contained within a
delicate shell. The valves of this shell are marked
about their centre with a reticulation of faint lines.
They are united along the hinder margins, and open
in front, the lower extremity in some species being
prolonged into a kind of spur of variable length.
The head is lengthened out in front to a kind of
beak, beneath which are the superior antennae (differing
greatly in the two sexes of the same species). In the
female these antennae are very small. On each side,
1

Baird's" British Entomostraca," p. 78.

WATER-FLEAS.

195

at the base of the head, the larger antennae are
attached. These consist of a single joint, dividing
upwards into two branches, the posterior of which
has four joints, the other three. Both branches are
furnished with long filaments, which in some species
are feathered throughout their length.
The eye of the Water-flea is spherical, and composed of about twenty lenses. The mouth is a somewhat complicated organ, and consists of a lip, two
mandibles, and a pair of jaws seated near the junction of the head with the body. The stomach is
plainly distinguishable as a long vessel curved upwards
at its lower extremity. The body consists of eight
segments, the upper of which only is attached to the
shell. An ovoid vesicle at the back of the first segment, subject to rapid contractions during the life of
the animal, is the heart. All the species of Daphnia
have five pairs of legs ; these are variable from each
other, and may be observed in motion through the
transparent shell. The eggs having attained a certain
period of development in the ovaries of the female
are ejected, and from that time until fully mature are
carried in the space between the back of the body
and the shell.
The Common Water-flea1 is found in almost every
pond and ditch during nine months of the year. The
male is much smaller than the female, and is comparatively rare. It has been asserted that their food
is entirely vegetable, but Dr. Baird was of opinion
after various experiments that on the contrary they
1

Daphnia pulex.
O 2

196

PONDS AND DITCHES.

subsisted chiefly on minute infusoria, and that they
are therefore wholly carnivorous.

COMMON WATER-FLEA.

A still larger species is that which may be termed

WATER-FLEAS.

197

1

the Great Water-flea, which has been found on
Bexley Heath, and other places around London. It
is as much as onefifth of an inch in
length, and two lines
broad. The terminal
spine at the lower
edge of the carapace
is very long, being
proportionately twice
as long as in the
Common Water-flea.
Their motion through
the water, says Dr.
Baird, is peculiar,
being a tumbling,
heavy sort of movement, and when seen
in their native ponds
they seem to keep
near the bottom.
When at the bottom
of the vessel in which

GREAT WATER-FLEA.

he kept them, he
frequently saw them turn head over heels throwing
a regular summersault, ten or a dozen times in succession.
Another species found in the neighbourhood of
London, commonly and plentifully, throughout summer and autumn, is the Spineless Water-flea,2 which
1

Daphnia Schczfieri.

2

Daphnia vetula.

198

PONDS AND DITCHES.

is sufficiently to be distinguished for our purposes by
the absence of the spine at the lower extremity of the
carapace. The smaller head and greater breadth of

SPINELESS WATER-FLEA.

the lower portion give an almost reversed pear-shape
to this species.

WATER-FLEAS.

199

There are several others which are also found more
or less commonly in Britain, but their differences and
distinctions are of more interest to the professed
naturalist than they would be to us, we will therefore leave the remaining four species unnamed, and
pass on to other creatures similar to the water-fleas,
and which are systematically associated with them.
In olden times, there was said to be a race of men
of gigantic stature, called Cyclops, and they had but
one eye in the middle of their foreheads. These
were the Cyclops of romance, but the Cyclops of
reality are by no means a race of giants, but minute
little Crustaceans, scarcely larger than the Water-flea,
and living in the same localities. They have also
been called Monocules, because, like the Cyclops of
old, they have but one eye in the centre of what may
be called the forehead.
The form of
the Cyclops1 is
very different
from that of
theWater-fleas,
being of an
elongated pearshape or clubshape, attenuated downwards, and
ending in two
elongated lobes
1

Cyclops signatus and Cyclops tenuicomis.

20O

PONDS AND DITCHES.

embellished with transparent setae of variable length.
From the upper extremity proceed two pairs of
antennae, one pair larger than the other, and from
these the species formerly obtained its name of
Quadricornis (four-horned). In the males the form
of the antennae is different, and serves to distinguish the sexes. In its progress through the
water the Cyclops moves with a rapid jerking
motion, which may be seen by holding a bottle
containing them up to the light. It will then be
observed that the principal propelling organs are its
oar-like feet, of which it has five pairs. Each foot,
which may be said to be double, consists of a common stem, from whence arise two-jointed branches,
liberally furnished with setae, or bristle-like appendages.
The fifth pair are rudimentary, and differ with the
sexes.
The females greatly preponderate, and are easily
recognised by their external ovaries, which hang suspended on each side of their bodies like miniature
clusters of grapes. Leeuwenhoek says that in specimens which he saw of this species he counted the
eggs, and found them arranged three or four in
breadth, and nine or ten in length; Dr. Baird says
that females are often seen carrying 30 or 40 eggs on
each side. Jurine, who watched carefully the hatching and increase of this species, says that " he has
seen one female isolated lay ten times successively,
but in order to speak within bounds he supposes her
to lay eight times within three months, and each time
only 40 eggs. At the end of one year this female
would have been the progenitor of 4,442,189,120

WATER-FLEAS.

20i

young, that is near four-and-a-half thousands of
millions. The first mother lays forty eggs, which at
the end of three months at eight layings during that
time would give 320 young. Out of this number he
calculates 80 as males (there being in every laying
a great proportion of females) the remaining 240 are
females/'1
It is easy to write, but not easy to comprehend
such an immense number. Let us suppose a man to
count this progeny, one by one, at the rate of sixty
per minute for twelve hours per day, for six days
a week,—a rate it would be impossible to sustain, — it would occupy him for three hundred
and twenty-nine years and a half, and upwards,
to count all the progeny of one female Cyclops
during twelve months. In reality such a progeny
never survives, because they are continually the
victims of predacious animals, but this is an estimate of the enormous possibilities of increase were all
conflicting and antagonistic circumstances removed.
Millions fall victims to trout and other fish, and the
delicate flavour of the former is said to be in a
great measure owing to a plentiful supply of this
living food. The Hydra, and the larvae of aquatic
and terrestrial insects all play their part in the work
of destruction, and thus lend a helping hand in
keeping down that teeming abundance of life which
would otherwise choke up our ponds, ditches, and
streams with animal life until existence under such
circumstances would become an impossibility.
1

Dr. Baird's "British Entomostraca," p. 190.

202

PONDS AND DITCHES.

The Vaulter, or Little Cyclops1 differs from the true
Cyclops in several particulars, viz., the female only
carries about one pouch of eggs,
the body more gradually attenuates
downwards, the size is smaller, &c.
It also is found in ponds and
ditches all the year round. It can
hardly be confounded with a small
species of genuine Cyclops which
is also very common in ponds,
but from which the females may be
distinguished at a glance by the
number of egg-pouches.
Another member of this family is
one which may be known as Castor?
which in like manner carries about
only one pouch of eggs. It has been
observed that the eggs of Castor are
carried about by the parent until the
young are hatched, whereas in the Cyclops they
are carried only till they approach maturity, and
are deposited before the young ones make their
escape. All the species of Entomostraca, as these
little Crustaceans are called, are produced in immense numbers, and constitute the natural food
of many aquatic animals in the mature, or larval
condition. If it were not for some such check on
over-population all our standing waters would teem
with them, on account of their rapid increase.
There still remains a group of minute little CrusCanthocamptus minutus.

2

Diaptomus castor.

WATER-FLEAS.

203

taceans which must not be entirely forgotten. These
are called scientifically the Cyfiridce, and the body is
enclosed in a covering of two
valves, like a bivalve-shell,
which in general appearance
closely resembles that of a
microscopical mussel, so,
much so that, as Miiller remarks, a person at first sight
would suppose that it was a
parasite inhabiting the shell
of some small mollusc. The
animal has two pairs of antennae, and two pairs of
teeth, with one eye. They
inhabit every pond and
ditch where the water is
stagnant, but not putrid.
The genus Cypris comprises
at least fifteen different species, and the individuals
swim freely in the water, moving in all directions.
This arises from the bundle of long feathery setae
which spring from the posterior antennae, by means
of which they can suspend themselves in the
water, or transport themselves through it with great
facility. The other genus, called Candona, with not
more than one-third the above number of species, is
deficient in this apparatus, and hence the little
animals have to rest content with crawling along
the mud at the bottom of the pools in which they
are found, or creeping over the aquatic plants which
grow there, without being able to suspend them-

204

PONDS AND DITCHES.

selves for the shortest time. These little creatures
are not so prolific as the Cyclops; but in some
of the larger species as many as twenty-four eggs
have been counted. The males have never been
discovered. The eggs are perfectly round, and are
deposited by the animal upon some solid body,
such as part of a plant, in a mass, which at times,

Straus says, consists of some hundreds from various
individuals, the mother fixing them to the surface of
the body on which they are deposited by means of a
glutinous substance, and then leaving them. The eggs
are hatched in about four days and a half. Before
maturity they pass through several moultings, the
frequency of which depends on the season of the
year.
The food of these little creatures consists of dead
animal matter, confervse, &c. Straus says he never
saw them attack living animals when they were well
and strong, but he has frequently seen them attack

WATER-FLEAS.

205

worms, when wounded and weak. Though dead
animal matter was their choice, they will not, he
adds, eat it when putrid. " They no doubt," writes
Baird, "also prey on each other, as I have often
observed individuals of one species devouring eagerly
the dead carcases of species different from themselves.
When the ponds and ditches in which they live dry
up in summer, they bury themselves in the mud, and
thus preserve their lives as long as the mud retains
any moisture, becoming as active as ever when the
rain falls, and again overflows their habitations. After
long-continued drought, however, when the mud becomes very dry and hard, they perish ; but the eggs
do not perish along with the parents, for they can
be hatched in four or five days after being placed in
water."
Instead of being fixed to one place, and condemned to live amidst eternal darkness, like the molluscous animals to which they bear such resemblance
in external covering, "they," to use the words of
Muller, " b y opening their valves, enjoy light, and
move at their will, sometimes burying themselves in
the mud, sometimes darting through the water, the
humid air of their sphere. If they meet any unforeseen object, they conceal themselves all at once in
their shells, and shut the valves, so that force and
address seek in vain to open them."
But what are the uses of these little Crustaceans
in the economy of nature ? This is a question which
Dr. Baird set himself to answer in the Introduction
to his volume. H e says, that " the greater number of
these little creatures are furnished with branchiae,

206

PONDS AND DITCHES.

either to their feet or maxillae, and when noticed in
their native habitats may be seen to have them in
constant motion, their action being seldom interrupted. One chief use, therefore, of them in the
economy of nature may be, as Miiller says, to ventilate the water day and night; and as they chiefly
reside in standing pools, they may thus be of great
use in preventing them from becoming putrid." And
again,—" I have no doubt that most of the Entomostraca are essentially carnivorous, and I have frequently seen specimens of Cypris in their turn, as
soon as dead, attacked immediately by quantities of
Cyclops, who, in a few minutes, had fastened themselves upon the dead animal, and were so intent
upon their prey that they were scarcely frightened
away from it by being touched with a brush. In a
short time, the Cypris might be seen lying at the
bottom of the vessel, the valves of the shell separated, and emptied of their contents. When, indeed,
we consider the amazing quantity of animals which
swarm in our ponds and ditches, and the deterioration of the surrounding atmosphere which might
ensue from the putrefaction of their dead bodies, we
see a decided fitness in these Entomostraca being
carnivorous, thus helping to prevent the noxious
effects of putrid air, which might otherwise ensue;
whilst they, in their turn, become a prey to other
animals, which no doubt serve their purposes also in
the economy of nature."

PONDS AND DITCHES.

207

CHAPTER XIV.
A Q U A T I C

LARViE.

THE higher forms of animal life have been included
in another volume of this series,1 where will be found
a record of the " birds, beasts, and fishes," of aquatic
habits, and hence there is fortunately no necessity to
repeat them here. Such of the reptiles as are aquatic
have also been illustrated in the same work; and, in
like manner, all mature insects which are generated
in marshes, hover over swamps, or spend their brief
term of existence in the neighbourhood of water,,
belong to that volume. In accordance with our
original definition, we have to concern ourselves only
with such insects as live immersed in the waters, and
as these chiefly pass only their larval stages in that
condition, the heading of this chapter indicates the
narrow limits within which we deem it necessary to>
confine our observations on the true insects of ponds
and ditches. Insects, according to the scientific limitation of the term, is much less diffuse than the
popular designation of " insect," which is often carelessly applied to any minute animal, whether spider,,
mite, cyclops, infusorian, wheelbearer, and even the
smaller worms. We are forced to make but a very
" Lakes and Rivers."

208

PONDS AND DITCHES.

PHANTOM LARVA.

a, head, b, thoracic aircells, c, abdominal aircells, d, oesophagus, e, gizzard, ft stomach, g, commencement of intestine,
i9 fan-like fin, k, four
branchial leaflets, m9 dorsal vessel.
1
2

brief passing allusion to some
of the most common and distinctive larvae which our localities furnish.
There is no insect-larvae
more common in still waters,
or better known than that
called the Phantom Larva. 1
No less than three elaborate
dissertations on its anatomy
and physiology, by most competent men, were published
almost simultaneously. 3
It
is familiar to every pond collector, and has been for
generations, and yet its lifehistory is not yet fully traced
through all its changes. It is
the larva of a two-winged insect, and so crystalline in its
nature that it moves like a
phantom through the water,
whence its name. As Dr.
Carrington justly observes,
" they are so translucent, that
unless you know what to look
for it is difficult to make them
out in the water. Their specific gravity also coincides
with that of water, so that
they are enabled to float

Corethra plumicornis.
Ray Lankester in " Popular Science Review," vol. iv., p.

AQUATIC LARV.E.

209

near the surface, or bottom of the vessel, without
apparent effort. They differ from all larvae with
which I am acquainted by this habit of remaining
suspended in mid-water, seldom seeking the surface
for purposes of respiration, as in the case of
other Diptera. I must not, however, allow you to
form the impression that their habits are sluggish
and inert. Far from this, their quietude is that of
the eagle, for, like that bird, they are watchful and
ready to pounce in a moment on any object moving
beneath them. Their spectral appearance, and the
mysterious manner in which they vanish and reappear
in unexpected places, will explain their name. One
habit seemed at first especially c uncanny,' the sudden
way in which they make a half-turn, like the needle of
a magnet, so that if we are examining the head, we
find the tail substituted in its place, and before we
have time to make out the details—presto ! the head
as suddenly appears ! Our phantoms are, I fear, not
so innocent as phantoms should be. We may rather
compare them with vampires which suck the life-blood
of unwary victims ;—a glance at the cruel armature
of the mouth will satisfy you of this fact. Our larvae
are very pugnacious; they are continually butting at
one another, after the manner of rams; and when
one commences an assault, the spectators are certain
to join in it."
In order that our figure of this larva may be com?
prehended in its details it will be essential to give an
outline of its structure. The body is about half-aninch long, gradually tapering to the tail, there are no
605; Prof. Rymer Jones in "Quart. Micro. Journ." vol. vii.
p. 99; Dr. B. Carrington, " Science-Gossip," April, 1868.
P

2IO

PONDS AND DITCHES.

feet or other appendages, except at the posterior
extremity. The third segment of the body is the
broadest and most prominent, and contains two airsacs {b); and again it is slightly humped at the ninth
segment, which also contains two air-sacs (c). The
skin is delicate, smooth, and punctate. On the sides
of the segments are scattered compound hairs. Terminating the body are four small branchial leaflets
(k) with four bristles above them and below, on each
side of the rectal opening, two hooked claws. Along
the mid line of the under side of the tail is a fanshaped cluster of bristles, (h, i) which serves at the
same time as a helm and a powerful scull. The head
(a) is compressed laterally, so that it appears wedgeshaped when seen from above. The frontal portion is
prolonged into a kind of snout. The eye is compound, formed of a number of button-shaped lenses,
those on the outer circle, resembling a chaplet of
beads. The black dots on the external surface of the
body are pigment cells which are easily detached after
death.
Circulation in insects is imperfect. Its motive
organ is the dorsal vessel (;//), in fact, a compound
heart, divided into segments by means of valves,
which allow the blood to flow forward towards the
head, but not to return. In this larva it is a wellmarked contractile organ, with delicate walls, broadest
near the tail. The oesophagus (d) is narrow when
empty, but capable of considerable distention. Its
walls are thin and consist of three layers. At the
lower end the oesophagus contracts and communicates
with a curious compressed gizzard (e) formed of two

AQUATIC LARVAE.

211

valves, not unlike the valves of the diatom called
Navicular and in like manner marked transversely with
raised parallel lines. A very narrow canal connects
this organ with the proper digestive cavity or stomach
(/), which is readily distinguished by its brownish
colour, derived from the large secreting cells of its
inner surface. Its chief direction is serpentine,
pointing downwards, and opposite the eighth segment
it contracts into a narrow small intestine (g), and at
the same time is joined by four threadlike biliary
ducts; hence it passes to an oblong colon and terminates in a short rectum (above h).
Insects are air-breathing animals, and the air is
carried to their tissues directly by vessels called
tracheae, kept open by means of an elastic spiral fibre
like the gas tubes so much in use. There are usually
two main longitudinal trunks, from which branches
proceed to the segments, and ultimately to every
nerve and muscular fibril in the body. The only
traces of longitudinal tracheae yet found in this larva
are the four air-sacs (b, c) in the third and ninth segments. These are attached in pairs. Seen from
above they are oval, with the surface irregularly reticulated with black dots. No trace of air-vessels
connecting these sacs was found. It is the opinion
of some observers that the two pairs of air-sacs {b> c)
only serve the purpose of floats to assist the larva in
its progress through water, but with this conclusion
Dr. Carrington does not agree.1
There are also the larvae of other two-winged flies,
1

" Science Gossip," 1868, p. So.
P 2

212

PONDS AND DITCHES.

which swarm in stagnant waters. Notably amongst
these are gnats and ephemerae, which, when arrived
at their mature condition, hover like clouds over
swamps and marshy places. Even the water-butt,
wherever water-butts are fashionable, contains the
ubiquitous larvae of the gnat. Standing waters are as
much a necessity to the large family of gnats as to
toads and frogs, as all those have experienced who
have attempted to spend a few quiet summer nights
in some of the fenny districts.
The female gnat deposits her eggs on the surface of
the water, in which her offspring are destined to pass
so much of the earlier portion of their career. These
eggs are glued together at the moment when they
are deposited by the mother, so as to form a mass
resembling a little boat, so beautifully constructed as
to float unharmed even during the roughest weather.
The eggs of which this little bark is composed are
conical in shape, and closed at one end by a kind of
lid, by means of which the mature insect is destined
to make its escape. The larva, as is well known,
does not bear the slightest resemblance to the perfect
insect, and its organs of respiration are singularly
modified in accordance with its habits. The head is
large and supplied with two feelers, or organs which
by their movements bring food to the mouth. The
thorax is larger than the head, and furnished with
tufts of hair.
At the end of the tail are certain fan-like fins, which by their motion help to
sustain the larva at the top of the water, where it
remains suspended, with the head downwards. In
such a position respiration would be impossible but

AQUATIC LARVAE.

213

for an arrangement of the breathing organs which
allows of free communication with the air. The
tracheae, or breathing pores, are connected with a
tube, appended to the last segment but one of the
abdomen, the perforated end being raised above the
water, so that the creature obtains from the air the
oxygen necessary for respiration.
After casting its skin several times, the larva being
fully grown enters the pupa state, and in this condition
still remains aquatic, occupying a position near the
surface of the water. In this altered condition it also
changes its position, so that the back of the thorax, and
not the tail, is brought into proximity to the surface.
" The problem to be solved " says Professor Rymer
Jones " is how shall the mature gnat escape from the
water without being wetted ? And when we consider
that neither the larva nor the pupa possesses instruments of locomotion, capable of enabling it to leave
its native element by crawling on shore, the difficulties
attending the change appear almost insurmountable.
It is evident that while swimming, in the position in
which the larva floats, the last change could not by
possibility be accomplished, as the bursting of the
integument would at once admit the water to the submerged gnat, and drown it at the moment of its
birth; but by the new arrangement the metamorphosis is easily effected, and that in a manner so
beautiful, that it is hard to say which is most admirable,
the simplicity of the contrivance, or the perfection
with which the object is accomplished. No sooner
has the encased imago become fitted for its escape
than the pupa, rendered more buoyant, raises its back

PONDS AND DITCHES.

214

above the surface; the protruded portion of the
pupa-case soon dries, and gradually begins to split in
a longitudinal direction so as to form, by its expansion,
a boat wherein the gnat swims upon the top of its
native pond; and sustained in this frail bark, formed
by its late skin, it gradually extricates its legs and
wings from their coverings, and is kept perfectly dry
until the expansion of its instruments of flight enables
it to soar into the air, and quit for ever the raft so
singularly provided for its use." x
Not many years ago, when the weather was unusually hot, there was great cry, and some alarm,
from Woolwich and other places on the Thames,
that the mosquitoes had come. Of course there
was discussion, and some affirmed that mosquitoes
are only gnats, with the sting rendered more
venomous by hot weather. Mosquitoes and gnats
are but popular names for two-winged insects
belonging to the same genus. What is called the
" mosquito " in India, or in North America, is only a
gnat, but in each case of a different species to that
which is most common in this country. Even here,
we have not one species of gnat, but several, and the
larvae of all are aquatic. It requires the knowledge
of an experienced naturalist to distinguish a Yankee
mosquito from a British gnat by the appearance only.
But no such scientific knowledge is requisite when it
becomes a question of feeling, rather than one of
judgment.
There is one anecdote extant of how mosquitoes
1

Prof. Rymer Jones. "Animal Kingdom," p. 396.

AQUATIC LARVJE.

2I

5

were once turned to good account in California. A
rogue had stolen a bag of gold from a digger and hid
it. Neither threats nor persuasions could induce him
t o reveal the place of its concealment. H e was at
last sentenced to a hundred lashes, and then informed
that he would be let off with thirty, provided he would
tell what he had done with the gold, but he refused.
The thirty lashes were administered, but he was still
as stubborn as a mule. H e was then stripped naked,
and tied to a tree. The mosquitoes, with their long
daggers went at him, and in less than three hours he
was covered with blood. Writhing and trembling
from head to foot with exquisite torture he exclaimed,
u
Untie me, untie me, and I will tell where it is."
•" Tell first," was the reply. So he told where it might
be found. Then some of the party with wisps kept
off the still hungry mosquitoes, while others went
where the culprit directed, and recovered the bag
of gold. H e was then untied, washed with cold water,
and helped to his clothes, while he muttered, as if
talking to himself, " I couldn't stand that anyhow I" 1
Wherever we read, or hear, of mosquitoes or gnats
it is in proximity to water, rivers, swamps, or bogs.
O f all the products of fresh water these are about
the most numerous and annoying. It is related, in
Butler's " Lives of the Saints," that Saint Macarius was
a confectioner of Alexandria, who spent many years
of his life in the desert, in penance and contemplation. " Happening one day inadvertently to kill a
gnat that was biting him in his cell, reflecting that he
1

Rev. Walter Cotton's "Three Years in California," p. 250.

2l6

PONDS AND DITCHES.

had lost the opportunity of suffering that mortification,,
he hastened from the cell for the marshes of Scete,
which abounds with great flies, whose stings pierce
even wild boars. There he continued six months,
exposed to those ravaging insects; and to such a
degree was his whole body disfigured by them with
sores and swellings, that when he returned he was
only known by his voice." 1
By far the most interesting feature associated with
mosquitoes, is one which was very recently illustrated
by Dr. Spencer Cobbold. There are several forms of
disease, such as elephantiasis, leprosy, & c , which are
fearful in their nature, and unfortunately prevalent in
hot climates. In these diseases the blood of the
human subject swarms with minute parasitic bodies,
which, however, never reach the perfect, or fully
mature condition, in that state. It has long been
subject of research to discover the perfect form, and
these researches have at length been successful. As
the result of experiment it has been shown that these
bodies are periodic in the blood. They conceal
themselves in the neighbouring tissues during the
day, and do not appear in the blood until five or six
o'clock in the evening, and from that time continue
to increase in number for some hours, and then again
diminish as midnight is approached. At this evening
time the mosquitoes are most ferocious, and sucking
the blood of the infected man, draw from him large
numbers of the parasites. Whatever may be the cause,
they have been shown to suck from the body a much
larger percentage of parasites than would exude at the
1

Butler's "Lives of the Saints," p. 50

AQUATIC LARVAE.

217

same hour from a mechanical puncture. We here
see a curious instance, very suggestive, of certain
parasites coming into the blood just at the hour when
the mosquitoes would be most active in removing
them, and that they perform this operation most successfully. Further than this, it has been demonstrated
that the parasites themselves attain their perfect
condition as soon as they are absorbed into the body
of the mosquito. It was at one time supposed that
the disease was distributed from individual to individual through the intervention of the mosquito, but
this has been shown to be an inaccurate assumption. *
The work which the mosquito performs is so far
beneficial, that it reduces the number present in the
blood of the diseased person, and that in their imperfect state, as found in the blood, the parasites
do not possess the power of increasing their species.
The question naturally arises, what becomes of the
perfect forms ? What is the rest of their life history ?
It seems to be this. The female mosquito, for it is
only the female that is a blood-sucker, gorged with
blood containing perfect forms, hastens to stagnant
water, or quiet water, especially margins of large
rivers, and there in accordance with her natural instinct, deposits her eggs, and almost immediately
dies. Her body falling in the water soon decays,
and within that body the living germs of the progeny
of parasites, the result of the perfected forms, become
diffused through the water. Natives drink of this
water, and with it the germs, or young parasites.
These parasites, entering the human stomach, soon
find their way into the blood, to be in turn sucked

2l8

PONDS AND DITCHES.

out by other mosquitoes, and thus the cycle is
completed.
Although these minute aquatic larvae are not inhabitants of the water in these more favoured lands,
yet this narrative will not be without its interest and
its lesson. It is well known that in many cases the
larval condition of parasitic worms is passed, or
partially so, in water. From this fact we may gatherthe salutary conclusion worthy of remembrance, that
drinking unfiltered water without boiling, from exposed places, even from rivers, is an act worthy of
strong condemnation.
Clouds of minute insects, smaller than gnats,
equally delicate, and still more rapidly passing away,
are to be seen hovering in the air in damp marshy
districts. These are the Ephemeridae, or day-flies, to
whom the name of Ephemera 1 has been given, on
account of the short duration of their lives. Some
of them, in their mature condition, never see the sun.
They undergo the final change into the winged stage
after the sun has set, and die before it reappears on
the horizon.
It has been stated that on the banks of some of
the rivers in France these flies appear in such numbers that the fishermen on those waters have a
current belief that they are showered down from
heaven, and accordingly call the living cloud, manna.
Reaumur, the distinguished naturalist, has stated that
he once saw them descend so fast, that the step on
which he stood by the river's bank was covered by
1

The antenna in our figure are exaggerated.

AQUATIC LARViE.

219

them, in a layer four inches in thickness, in a few
minutes. H e compares their falling to that of snow,
with the largest flakes.1 Scopoli also writes of
similar swarms in Carniolia at certain seasons of
the year.
And these also are " children of the
waters."
Kirby and Spence 2 enumerate a long list of genera
of insects, the larval condition of
which is passed in the water.
" Some walk on the ground under
water; some move in mid-water,
either by the same motion of the
legs as they use in walking, or by
strokes, as in swimming; others
for this purpose employ certain
laminae, which terminate their
tails as oars; others, again, swim
like fish, with an equable motion;
some move by the force of the
water which they spirt from their
extremities; others, again, swim ^. v
\
about in cases, or crowd over the Jsjrf%S$*z~r~
submerged bottom;

and others LARVA OF EPHEMERA.

walk even on the surface of the
b Natural size,
water."
We have nearly fifty different species of dragonflies, and their larval conditions are passed in the
water. Here are then many aquatic animals whose
history may be studied, until they emerge from
1
3

Reaumur's "Memoirs," vol. vi. p. 485.
"Introduction" (1858), p. 442.

220

PONDS AND DITCHES.

their watery element and disport themselves in the
air. Eleven months of the life of a dragon-fly are
spent in the water, and only one on wings, making
up the natural term of its existence. These larvae
are very active, being provided with six legs, which
they employ to the best advantage. The large
head is ornamented with enormous eyes, which
serve to impart a terrific appearance, and its everhungry jaws are concealed by
a mask. " Not only does the
immature Dragon-fly walk over
the bottom of the pool or
stream it inhabits, but it can
also leap for a considerable
distance by a most curious
contrivance. By a syringe-like
apparatus lodged in the end of
its body, it discharges a stream
of water for a distance of two
or three inches behind it, thus
LARVA OF DRAGON-FLY. propelling the insect forwards.
This apparatus combines the
functions of locomotion and respiration. There are, as
usual, two breathing pores on each side of the thorax;
but the process of breathing seems to be mostly
carried on in the tail." From the larva this insect
passes into the pupa stage, also in the water. It is;
still active, and as voracious as ever. " When the
insect is about to assume the pupa state, it moults its.
skin—the body having outgrown the larva-skin; by a
strong muscular effort a rent opens along the back of
the thorax, and the insect, having fastened its claws

AQUATIC LARVAE.

into some object at the bottom of the pool, the pupa
gradually works its way out of the larva-skin. It is
" V ; i«6y

«vy*;

HAUNT OF THE DRAGON-FLY.

now considerably larger than before. Immediately
after this operation its body is soft, but the crust soon

222

PONDS AND DITCHES.

hardens." At length, when the time for its final change
arrives, the pupa climbs up some plant near the surface of the water. Slowly and gradually as its prisoncase splits open, the winged insect escapes, and after
resting awhile to dry and harden its flabby wings, it
starts on its last career of insecticide—
" To-day I saw the dragon-fly,
Come from the wells where he did lie.
An inner impulse rent the veil
Of his old husk : from head to tail
Came out clear plates of sapphire mail.
He dried his wings ; like gauze they grew ;
Through crofts and pastures wet with dew
A living flash of light he flew."

Any one who observes the rapid flight of the
dragon-fly, and indeed the majority of insects, must
be impressed at once with the enormous rate of
speed in proportion to size which they attain.
Leeuwenhoek narrates an instance, in which he was
an eye-witness of the capabilities of the dragon-fly
and the swallow in rapidity of flight. The bird and
the insect were both confined in a menagerie about
ioo feet long, and apparently their powers were
fairly tested. The swallow was in full pursuit, but
the little insect flew with such astonishing velocity
that even this bird of rapid flight and ready evolution was unable to overtake and entrap it; the insect
eluding every attempt, and being generally six feet
before it. " Indeed," write Kirby and Spence,
" such is the power of the long wings by which the
dragon-flies are distinguished, and such the force of
the muscles which move them, that they seem never
to be wearied with flying. I have observed one of
them sailing for hours over a piece of water, some-

AQUATIC LARVAE.

223

times to and fro, and sometimes wheeling from side
to side, and all the while chasing, capturing, and
devouring the voracious insects that came athwart
its course, or driving away its competitors—without
ever seeming tired or inclined to alight." 1
An anonymous writer in " Nicholson's Journal"
calculates that in its ordinary flight the common
house-fly makes with its wings about 600 strokes,
which carry it five feet every second; but if alarmed,
he states that their velocity can be increased six or
sevenfold, or to 30 or 35 feet in the same period.
In this space of time a racehorse could only clear
90 feet, which is at the rate of more than a mile in
a minute. Our little fly, in her swiftest flight, will
in the same space of time go more than the third of
a mile. Now, compare the infinite difference of the
size of the two animals, ten millions of the fly would
hardly counterpoise one racer, and how wonderful
will the velocity of this minute creature appear ! Did
the fly equal the racehorse in size, and retain its
present powers in the ratio of its magnitude, it would
traverse the globe with the rapidity of lightning.
It is curious to speculate upon the result of dispensing with this balance of power, by which nature
restricts the dimensions of an insect within certain
bounds, even in the case of a single species. Let
us suppose the wasp or the stagbeetle, as has been
suggested, expanded in bulk to an equality with the
tiger or the elephant, enclosed in an impenetrable
armour, furnished with jaws capable of crushing the
solid trunk of an oak, and, withal possessing enor1

Kirby and Spence, " Entomology," p. 35.

224

PONDS AND DITCHES.

mous powers of flight, from which escape would be
hopeless, what could possibly resist the ravages of
such destroyers, or how could the world support
their ravages ? But, fortunately, each creature is organised and accoutred for the position it is intended
to occupy, and harmonized with its surroundings, so
that a limit 'is fixed to its capacity for mischief.
We may indulge in comparisons like these, in order
to appreciate the wonderful powers of which they
are the possessors, but, at the same time, such speculations can only serve to strengthen the impression
of the unity and harmony of a world controlled by
a supreme and all-wise Intelligence.
It cannot be supposed that any one who wanders
by the margins of streams, lakes, or ponds, will pursue
such an avocation long without becoming cognisant
of certain cylindrical cases, fabricated of all kinds of

CADDIS CASES.

trifles, agglutinated together into a habitation for what
are called "Caddis-worms." These cases are most
interesting examples of insect homes, as wonderful
and instructive as birds' nests, and as variable in
appearance. Caddis-flies are little, unobtrusive insects,

AQUATIC LARViE.

225

with four membranous wings, and little that is attractive about them. We have many species, and all,
with one or two exceptions, have aquatic larvae, and
these latter construct for their residence the tubes
called caddis-cases. One common form consists of
a cylindrical tube, of equal diameter throughout,
formed of fragments of leaves, and other vegetable
substances, neatly arranged in a spiral manner,
with the spiral turned from left to right, or from
right to left. 1
The inhabitants
of these cases
CADDIS CASE
have the power
'
of turning themselves, so that their heads may be
thrust out at either end. Other cases are fabricated of shells, seeds, pieces of wood,
and rushes arranged in various order,
so as to give great variety to their
general appearance, more or less
beautiful, according to the materials
available to the little architect. Sometimes such materials have been artificially supplied in order to test the
building instincts of the little larvae,
and the result has been the construction of most ornamental cases.
A tolerably common case is made
from pieces of moss, kcut into con- CADDIS CASES.
venient lengths, 2 but an equally abundant form of case
is that in which the insect by no means confines itself
to vegetable fragments, but uses all such objects
1
2

Phryganea grandis and other species.
Limnephilus rhombicus.
Q

226

PONDS AND DITCHES.

as we have indicated above, or indeed almost any
substance, without the slightest semblance of order
or selection. 1 " A conchologist might frequently
examine these cases with profit, for a good miscellaneous shell-case will give a better idea of
what fresh-water molluscs may inhabit any particular spot than probably would many hours of
dredging and searching. It matters little whether
the shells be empty, or still contain their proper
inmates, these latter must submit to be dragged
about at the will of the creature that has thus
unceremoniously pressed them into its service; and
if they do not die in that position, they must
patiently await the time when, after the escape of the
perfect insect, the binding materials of the case may
rot, and set free the various matters composing it." 2
Other cases are formed of sand, either wholly or
with long twigs attached to the outside.
Small sand cases, round and quadrangular, straight or curved, cylindrical
or tapering, according as they are the
work of different species will commonly
be found in ponds, especially one of a
larger kind, with the upper surface projecting at one end in such a manner
that it serves as a cover and protection
to the insect when it protrudes its head
from the case in search of food.
The
knowledge of the existence of these
little case-makers is by no means
CADDIS CASE, 0 f r e cent date.
Hear what Aristotle
1
3

Limnephilus flavicornis.
R. M'Lachlan in "Science-Gossip," 1868.

AQUATIC LARViE.

227

has written about them, long before microscopes
or naturalist's clubs were thought o f : — " T h e r e
is a small, worm-like creature,
called Xylophthorus; its variegated head extends beyond its
case, its feet are at the upper
extremity, as in other worms;
the rest of the body is contained
in a case made of a substance
like a spider's web, around and
outside of which are chips of wood, so that the animal
walks about with this attached to it. These creatures
are attached to their cases as an oyster to its shell; the
whole of the case is joined to the worm, and does not
fall out of it, but can be drawn out as if they grew
together. If anyone pulls off the case the animal
dies, and becomes as helpless as a snail without its
shell. As time advances this worm becomes a
chrysalis like a caterpillar, and
lies without motion ; but the
nature of the winged creature
that is produced from it has not
been ascertained."
The very numerous order of
Beetles is one of particularly terrestrial habits, yet there are
amongst them several genera in
which either the larva or the perfect insect, or both, are aquatic.
The most familiar example of
WATER-BEETXE.
this is the Great Water-beetle, 1 a
Dyliscus marginalis.

228

PONDS AND DITCHES.

very "ogre" amongst the unprotected of pond
insects.
Of all the ferocious creatures which disport themselves in the waters commend us to the larvae of
the Great Water-beetle. "Once I kept one in a
basin of water," says Mr. Mclntyre, "for a fortnight,
during which time he ate seven or eight tadpoles, besides sundry earthworms, and grew
so large that he cast his skin twice.
If a small stick were presented to
him, he would grasp the end boldly;
that mode of testing his bravery
being deemed more prudent than
offering him a finger, which, judging by his manner of despatching
tadpoles might have been painfully made acquainted with the
sharp points of his mandibles.
One gripe was sufficient to settle
any tadpole, and was always taken
through the sides, apparently quite
transfixing the poor little wretch,
LARVA OF WATERwhich quivered while life lasted,
BEETLE.
its enemy meanwhile keeping tight
hold and sucking its juices till nothing but the
blanched skin was left to tell the tale. Earth-worms
were more trouble to him, since owing to their
violent struggles he was obliged to divide the larger
ones and eat them piecemeal."
The mature insect, which is also aquatic, is no less
terrible. Those who make the mistake of introducing
these large beetles into their aquaria for the sake of

AQUATIC LARVAE.

229

their activity and imposing appearance, soon discover
what a mistake they have made by the gradual disappearance of all the smaller insects and animals.
If they are favoured with an aquarium at all, it
should be one in which there is nothing for them
to harm, and the top should be so covered that
they cannot make a moonlight escapade.
The Whirligig Beetle * is a much more respectable
member of insect society, conducting itself in a lively
but much less ferocious and bloodthirsty manner.
Of all aquatic insects, none surpass in interest
those belonging to the true Hemiptera, or, as usually
termed, "the bugs." Not that there is much external
resemblance between these aquatic members of the
family and their metropolitan representatives, but
the latter is a strictly urban application of the
name. In the United States the name " bug " has
a very wide application, since it is often applied to
beetles, but its intermediate restriction to those insects
which are known to entomologists as true Hemiptera
is the most reasonable. The aquatic bugs which are
most familiar are the Nepa and the Notoneda; the
" boatman" and the " water scorpion." Such of
these insects as possess wings have always four, of
which the outer, or upper pair are firm and leathery in
texture in the basal half, and membranaceous in the
outer half. The two we have named, especially the
" water -boatman," are very common in stagnant
waters, both in the larval and mature condition.
The largest, and most imposing of these insects is
1

Gyrinus natator.

230

PONDS AND DITCHES.

one which has also been called the " water-scorpion,^
but a very different insect from the Notonecta. On
account of this confusion of names it will be necessary to refer to the large water scorpion by its other
name of Ranatra}
It has a long abdomen, of a
vermilion red colour, terminating in two long setae,,
which are as long as the abdomen. This creature
inhabits the water in every stage of its existence.
The perfect insects leave the ponds and ditches they
inhabit in the evening, and may be found on the
mud at their margins. Like most other winged
water-insects they fly in the night, sometimes to a
considerable distance, in search of a better home
should their own pools be nearly dried up. This is.
rather a ferocious carnivorous insect, living upon other
insects which it holds between its fore feet, whilst it
pierces, and sucks them with its beak or rostrum.
The aquatic family of bugs which are called
Hydrometra live on the surface of running or stagnant water, where they propel themselves rapidly by
the rowing motion of their second and third pairs of
legs, feeding upon any insects that may come in their
way, catching them by springing upon them, with a
capacity for diving when alarmed. There are several
species of Hydrometra, but we are not aware that
they are sufficiently popular to have acquired a vulgar
name. They attain from four to seven lines in length,
and at least three species are common on stagnant
water, whilst a fourth is attached to running streams,,
up which it runs with celerity against the current.
1

Ranatra linearis.

AQUATIC LARWE.

231

The Velia} another of the same kindred, is common on clear streams, smaller in size, but gregarious
in habits, living in company on the surface of the
water, and not unlike in appearance to little spiders.
They move rapidly by a succession of leaps.
We might also note at least eighteen different
species of Corixa, some of which are confined to
brackish water, such as the ditches near Gravesend,
but others are found on inland pools, and other
stagnant waters. Not less than three kinds are
decidedly common, and one 2 has the reputation of
being very common. These by no means exhaust
the list of " water-bugs," even of the most common.
There is a little fellow, fond of creeping about slowly
on the water amongst duckweed, and whose portrait
was drawn by Curtis, more than half a century ago.8
Another, as rapid in motion as the latter is sluggish,
swims by means of its four hind legs.4 This
will suffice to give some idea of the nature and
habits of an obscure and but little known, group of
insects, with a special fondness for ponds and ditches.
It is affirmed that the insect eggs which are collected
as food by the Mexicans, are those of some kind of
water-boatmen. These eggs are collected from the
lakes and made into a kind of cakes called " hautle,"
or more probably by some Mexican name, of which this
is a corruption. " On the lake of Texcoco " writes
one Brantz Mayer, of Mexico, in 1844, " I saw men
occupied in collecting the eggs of flies from the
surface of plants and cloths arranged in long rows
1
2

Velia currens.
Corixa sahlbergi.

3
4

Limtiobates stagnorum.
Naucoris ciinicoides.

232

PONDS AND DITCHES.

as places of resort for the insects. These eggs formed
a favourite food of the Indians long before the
conquest, and when made into cakes resemble the
roe of fish (caviare) having a similar taste and
appearance. After the use of frogs in France and
birds' nests in China, I think these eggs may be considered a delicacy, and I found that they are not
rejected from the tables of the fashionable inhabitants
of the capital." The eggs of three kinds of insects
have been identified as forming this delicacy, two of
which are species of Corixa, of which we just stated
that eighteen kinds are inhabitants of Britain, and
the other insect is a kind of Notonecta.
Thus rapidly have we executed our pond-hunting
excursions, and at its close find the subject not only
unexhausted, but even with more unwritten than we
could have wished, and only the slightest glimpse
afforded of the multitudinous life of still waters. Roaming over such a wide field as the whole of the vegetable
and animal life of fresh waters it could hardly be anticipated that these little books could be rendered sufficiently rich in detail to serve as text-books; all they
can claim for themselves is to serve as introductions
to studies for which text-books will be as essential as
ever. One cannot contemplate an open page of the
book of Nature, like the present—one, perhaps, but
little scanned, seldom read, or pondered over—without
being deeply impressed with the prodigality with which
the wonders of an all-powerful and all-wise Creator are
scattered to the furthest limit of a wonderful world.
The same order, the same fitness, the same completeness which characterises all the visible universe, is

AQUATIC LARV.E.

233

again represented in that part which is so minute
in all its details as to be invisible to the naked
eye. " Of all the blessings which the study of nature
brings to the patient observer, let none, perhaps, be
classed higher than this ; that the further he enters
into those fairy gardens of life and birth, the more he
learns the awful and yet most comfortable truth, that
they do not belong to him, but to One greater, wiser,
lovelier than he; and as he stands, silent with awe,
amid the pomp of Nature's everbusy rest, hears, as of
old, " the Word of the Lord God walking among the
trees of the garden in the cool of the day." l
1

Kingsley's "Glaucus."

234

PONDS AND DITCHES.

C H A P T E R XV.
ON COLLECTING AND EXAMINING.

A VOLUME of this character could hardly be considered complete if it did not furnish some hints to
the novice for the prosecution of " rambles," such as
the preceding pages assume. In many other rambles
little advice is needed, since the objects are large, or
at least visible without searching, fish and other
aquatic animals excepted. On the other hand, we
have professed to deal largely with the invisible, not
so much so on account of their size, but chiefly
because of their aquatic habits. In this sense our
objects are on an equality with the fish just referred
to, they are hidden in the waters and must be brought
to the light of day before they can afford either amusement or instruction. Hence some advice from one
who has often hunted in ponds will be a necessary
and welcome close for the volume.
On this subject, as most other out-door pursuits,
everyone has his own " crotchet," and hence different
methods are in vogue for the attainment of the same
object, some persons preferring the one and some
another. Where such different methods seem to
merit notice we need not apologize for a plurality of
modes. During the progress of the work we have
already dropped a hint or two by the way, applicable

ON COLLECTING AND EXAMINING.

235,

to the subject then under consideration.
Plain
matter-of-fact suggestions are hardly essential, yet we
cannot forbear at the outset reminding our readers
that pond-hunting is not drawing-room work. If we
would be successful we must enter upon this, as
upon all other work, with zeal and resolution. In
order to do this without injury to health proper preparation should be made. To go abroad, and wander
over the low swampy parts of a heath, a boggy moor,
or beside marshy ditches, the first necessity is to have
the feet well protected and encased in sound boots,
though they may not be handsome. Standing about,
it may be for hours, in oozing, penetrating swamps
will prove dangerous work unless this precaution be
taken. Some ponds and some ditches may, like
canals, have a sound, hard road beside them, but this
is the exception rather than the rule. Yet no one
need to have wet feet because they choose to study
that phase of life which is manifested in ponds and
ditches.
Preparation must also be made for conveying home
the spoils of the chase for subsequent examination.
In collecting land-plants a botanical vasculum is all
that is requisite, but this would afford poor accommodation for aquatic objects. The majority of these
should be kept in water, and hence some arrangement of bottles is essential. Pill-boxes may do verywell for the snails, and even the beetles, but for little
else. A good supply of wide-mouthed bottles, fitted
with corks, is indispensable. They may go into all
the pockets, or cases may be purchased at some of
the opticians, fitted with bottles, and adapted for the

236

PONDS AND DITCHES.

work. We will not pretend to say which is the
cheapest or the best.
In addition to the bottles some persons recommend
oil paper, waxed cloth, or gutta percha tissue for
wrapping the larger plants, filamentous Algae, and such
objects, or a small vasculum may be applied to this
purpose, if preferred. Many more hints than we can
give are contained in Nave's " Handy Book to the
Collection of Algae and other Objects," translated
from the German. Provided in this manner for securing the spoil, the next consideration is, how to obtain it.
Most of the things which one
is likely to see will be out of
reach of the hand. Some of
these may be reached with a
walking-stick, furnished with a
hook at one e n d ; others, still
further off, will have to be
brought to the shore by some
COLLECTING HOOK
other contrivance. A triple
OR "DRAG."
iron hook, such as we have
figured, attached to a cord
and thrown over the bed of weeds, in which it
will sink by its own weight, and then drawn gently
to the shore, is one method. Others recommend a
kind of rake, or a longer stick—let each be persuaded
in his own mind.
There will be minor objects out of reach, for which
the hooks are useless, and some means of dipping in
a wide-mouthed bottle will be necessary. The original plan was to attach a wide-mouthed bottle with

ON COLLECTING AND EXAMINING.

237

a spreading lip, by means of an elastic band, to the
end of a walking-stick; since that time a brass ring has
been devised which fits round the neck of the bottle
like a collar, and may then be screwed into the end of
the stick. This plan secures greater firmness, and is
to be preferred. When a dip with the bottle has been
made, it may be held up to the light to see what it
contains, and probably some objects will be so minute
that the naked eye will be insufficient to give satisfaction. In that case a pocket-lens, of an inch focus, or
a combination of two or three lenses, will be essential.
No one should dream of going out on an excursion in
search of objects of natural history without a pocketlens and a pocket-knife. Without these essentials he
had better stay at home, for only vexation and disappointment will be in store for him.
Taking for granted that the bottle contains a good
dip, some of the water may be poured off carefully,
and the residue transferred to another bottle, corked
and pocketed, and another dip taken. If plants or
animals of a visible size are the objects of search, a
piece of muslin or linen in the pocket will not occupy
much room, and be used as a strainer, and less water
will have to be carried away. For minute objects
some will prefer a small japanned case fitted with
corked tubes, six or eight, and not too large for
the breast pocket. Beyond these hints experience
will be the best guide, and necessity will become
the mother of invention.
Arrived home again with the results of the day's
excursion, the bottles must be all uncorked to allow
of access to the air, then the contents may be trans-

238

PONDS AND DITCHES.

ferred to tumblers, or other larger vessels, rain, or
pipe-water added, and the stores put on one side, in
a light and cool place until next day, or they may be
examined at once, according to convenience. It may
be that already a small fresh-water aquarium has been
extemporized, and into this all the contents of the
bottles may probably be transferred. This will be
determined by the objects and desires of the collector.
Should the object be merely to get together a number
of illustrations of pond life, regardless of whether
they eat each other or not, they may be mixed; but
if other and higher aims prevail, each bottle will first
be examined to see what it contains, and disposed of
in a more systematic manner.
The examination of the minutest objects cannot be
attained without the use of the microscope. Anyone
in possession of such an instrument will need no instruction from us how to use it, anyone not in such
happy possession would skip those instructions if we
were to give them ; therefore, either way the labour
would be lost. This assumes that the few lines which
we could devote to introductory hints as to the use of
the microscope would scarcely serve the purpose of one
who has everything to learn, and not be requisite for
one who has already learnt by experience. There is
a great deal to be learnt as to the best methods of
employing a microscope, but so many useful books
have been written specially on this subject that we
may pass it over here.
Anyone who has had sufficient interest in the subject to accompany us as far as this last chapter, is on
a sure road to obtain a microscope for him or herself,

ON COLLECTING AND EXAMINING.

239

if not the possessor already. If the idea has never
presented itself to the mind in such a definite shape,
let us suggest it. The use of this marvellous instrument is not only the addition of new eyes, but an introduction to a new world, in which the appearance of
its inhabitants is wholly different from those of the
visible world. If only as an amusement, it is the most
wonderful toy that was ever invented, and it has the
advantage over all other toys that its variety is practically unlimited. The manipulation is simple and
soon acquired, and the cost is so minimised that it is
no longer an obstacle. Depend upon it that even if
employed only as an amusement instruction will come
unawares.
"What better encouragement and direction can
possibly be given to the exercise of the observing
powers of a child than to habituate him to the employment of this instrument upon the objects which
immediately surround him, and then to teach him to
search out novelties among those less immediately
accessible ? The more we limit the natural exercise
of those powers, by the use of the methods of education which are generally considered to be specially
advantageous for the development of the intellect,
the more we take him from fields and woods, from
hills and moors, from river-side and sea-shore, and
shut him up in close school-rooms and narrow playgrounds, limiting his attention to abstractions, and
cutting him off even in his hours of sport from those
sights and sounds of Nature which seem to be the
appointed food of the youthful spirit, the more does
it seem important that he should in some way be

PONDS AND DITCHES.

34o

brought into contact with her; that he should have
his thoughts, sometimes turned from the pages of
books to those of creation, from the teachings of man
to those of God." And again, the same author
writes, —" A single rural, or even suburban walk, will
afford stores of pleasurable occupation for weeks in
the examination of its collected treasures. A large
glass jar may be easily made to teem with life, in
almost as many and varied forms as could be found
by the unaided eye in long and toilsome voyages
over the wide ocean; and a never-ending source of
amusement is afforded by the observation of their
growth, their changes, their movements, their habits.
The school-boy thus trained looks forward to the
holiday which shall enable him to search afresh in
some favourite pool, or to explore the wonders of
some stagnant basin, with as much zest as the
keenest sportsman longs for a day's shooting on the
moors, or a day's fishing in the best trout-stream ; and
with this great advantage over him, that his excursion
is only the beginning of a fresh stock of enjoyment,
instead of being in itself the whole." 1
As an illustration of these remarks we may detail
a small item of experience. One Saturday afternoon
in February, the weather being still cold, and rather
uninviting, we spent a single hour on Hampstead
Heath in filling two or three small bottles from the
standing pools in the lower parts of the heath. There
was not much to excite attention, a little green
thready scum on some of the pools, and some float1

Carpenter, " O n the Microscope," p. 28.

ON COLLECTING AND EXAMINING.

241

ing debris of vegetable matter on others, the latter
coated with a dirty-looking brownish film. A few
dips from some of the pools could be seen to contain a few active Cyclops. Nevertheless, we took
home in all about two ounces of water, containing
Conferva and some dirty scum, with a few Cyclops,
and a little of the small duckweed floating on the
top. This collection we transferred at once to a
common tumbler, with a little additional water,
and thus extemporized an aquarium. Most of the
conferv and debris settled at the bottom. The
duck-weed covered the surface. Cyclops floated
in the region intermediate in free and undisturbed
vivacity.
A month passed after this excursion, and before
these lines were written ; the water remained as clear
and fresh as at the first, and the Cyclops as healthy
and vigorous. On the surface the duckweed was
still green and growing. But, during that month,
this tumbler of pond-life gave full occupation for all
our leisure. We needed no fresh excursion, for the
results of the first were not exhausted, and yet it was
made at one of the most unfavourable seasons of the
year. The Cyclops consisted of two species, one of
them with the antennae consisting of seventeen
joints, 1 and the other of only twelve.2 The former
were twice as large as the latter. Some females
were bearing their pouches of eggs. One large
female was also almost covered with a parasitic
Vorticella, or bell-animalcule. The bells, at the
1

2

Cyclops tcnuicornis,
R

Cyclops serrulatus.

242

PONDS AND DITCHES.

end of long retractile stems, jerked up and down,
catching their prey. Amongst the debris at the
bottom of the glass we found also another bellanimalcule, attached to old Conferva, the bells
much smaller, and the mouth less expanded.1
Crawling amongst the debris were numerous waterbears, large and small, and these furnished amusement for an entire evening with the microscope. We
had sometimes four specimens at the same time upon
the slide, creeping about and exhibiting their claws
in vain attempts to hold upon the slippery glass.
Mixed with the same material, on subsequent occasions, no less than three kinds of Rotifers or wheelbearers were found; the large common rotifer, and
two free-swimming smaller active species. It was
amusing to see the large rotifer creeping about after
the mode of those caterpillars which are termed
loopers. Stretching out and holding on by the proboscis, then drawing up the foot nearly to the head,
fixing it, and then advancing the proboscis as before,
and thus migrating from place to place. Nearly
every examination from this store afforded some new
object. The tumbler of pond-life seemed to be inexhaustible. There were Diatoms, and one solitary
species of Desmid, green Algae, both unicellular and
filamentous; Infusoria of various kinds, from the
large Stentor down to the minute "Ptyxidium." Some
were undergoing division, and what was previously
only one individual was gradually becoming two.
Even lower still in the grade of existence were two
Vorticella microstoma.

ON COLLECTING AND EXAMINING.

243

1

kinds of Proteus or Amoeba, and the Sun-animalcule,
or Actinophrys, not one or two individuals only, but
by scores. Then there were the very interesting
creatures called Euglena, and of these no less than
three different kinds; one, common everywhere,
spindle-shaped and active,2 another larger, but more
sluggish, and only seen singly,3 and finally a small
disk-shaped flat species,4 wavering about like a tiny
green leaf, and all exhibiting their bright red eyespot. But it would become tedious were we
merely to enumerate all that we found successively,
in this little tumbler of water; it must suffice
to say that we do not regard it as exhausted,
but whenever an opportunity permits we take a
bit of the sediment from the bottom, place it
upon a slip of glass, add a drop of water, cover it
with a covering-glass, and then examine it with a
quarter-inch objective.
If one short ramble, of only an hour's duration, at
a most unpromising season of the year, could give us
continued occupation for all our leisure during an
entire month, it must be presumed that later, and at
a more congenial season, the results of an excursion
would be almost inexhaustible. It is not the mere
determination of the names of an indefinite number
•of objects that is desirable. This is by no means a
primary advantage, unequal to the interest and importance of watching and tracing the varied changes,
stages of development, and method of life in minute
1
3

Amoeba Umax and Amoeba gicttula.
Euglena spiro^yra.
R 2

2
4

Euglena viridis.
Euglena pleuronecUs.

244

PONDS AND DITCHES.

organized beings such as these, which on account of
their small size have been but little studied* and the
life-history of which is comparatively unknown. That
mode of increase which results from budding, or
division, is not represented in the larger animals
which come under the cognizance of the unaided
eye, but these are methods common amongst such
microscopical creatures as those which abound in our
ponds and ditches.
Cells have been devised specially for the examination of this class of objects, the main principle of
which is to maintain a supply of water which can be
kept up day after day, whilst the thickness of the
cell is reduced as much as possible, so as to bring it
within the limits of the higher powers of the microscope. The thinnest form of cell is a kind of growing cell, one end of the slide being dipped in water,
so that it is kept filled by capillary attraction, wThen
not under examination. Very small Infusoria would,
however, flow out as easily as the water flows in, so
that after all much will have to depend upon the
ingenuity of the operator, to adapt the various contrivances to his own individual circumstances.
The preservation of most of the aquatic objects
to which we have directed attention cannot be said
to be satisfactory. There are very few of the animal
objects which will suffer mounting as permanent preparations. Considerable improvements in mounting
have taken place of late years, but these can never
equal the living animal with its organs in action ; and
no wheel-bearer, mounted in ever so perfect a manner,
can compete with a living wheel-bearer under the

ON COLLECTING AND EXAMINING.

245

microscope, with its circlets of cilia in rapid movement and the masticatory organs in operation.
The filamentous Algae, or Confervas, can be floated
in a plate or shallow dish, slips of paper passed under
them, and then lifted gently out of the water in such
a manner that the Algae become deposited on the
paper, just as they floated in the water. In this
manner many, if not all, of the thread-like water-weeds
may be dried and preserved for future reference, and
these will generally adhere to the paper with all
requisite tenacity.
The unicellular Algae are not so easily preserved,
except as microscopical preparations, and these deteriorate by the derangement of the endochrome and
change of colour. The beautiful green of the Desmids,
vanishes in the course of a short period, and the
empty fronds exhibit an ill-defined outline through
excessive transparency. Diatoms, of course, are the
great exception to this rule. The siliceous frustules
are practically indestructible, and will remain almost
for ever without change. This is one feature which
has contributed to the popularity of the study of the
Diatomacese, a popularity which has never been
equalled by the other unicellular Algae.
The difficulty still remains unsolved as to the best
manner of preserving specimens of Desmids, and
such like small Algae, for future reference. Some
have adopted the primitive method of drying them
like a green stain on paper, which is very unsatisfactory. Others have spread them in a thin film on
strips of glass and allowed them to dry; but glass is
easily broken, and the drying will shrivel the specimens

246

PONDS AND DITCHES.

so that moisture cannot recover them. This latter
difficulty belongs to every method. The best mode
known to us is to spread the minute Algae on small
strips or squares of thin mica; by moisture applied tothese, for a period sufficiently long, much of the
original form will be recovered, and detail enough to
discriminate between species.
But, as to the minute animals, the transparent
Infusoria, the delicate Polyzoa, the water-bears, mites,
and many others, what can be said ? We fear that
all we can recommend is that they should be studied
as much, and as often as possible in the living state.
The pencil should be freely employed in sketching
them in all the positions they assume, and in portraying all their changes, and every detail of their
structure. Hereafter, we doubt not, considerable
improvement, implying great advancement in the art
of mounting objects for the microscope, will overcome many of the difficulties. Staining tissues
already has done a great deal, and possibly stained
Infusoria will not be amongst the impossibilities of a.
future.
Whilst examining the wheel-bearers and ciliated
Infusoria under the microscope it will often be found
advisable to devise some method whereby the form
of the stomach and viscera, or of the movement of
the cilia, may be determined. It is usual to do this
by dissolving indigo, or some other colouring matter,,
in the water. This will enable one to trace the current
into the bodies of the animals themselves, and the
vortex caused by the vibration of the minute cilia will
be more distinctly seen. In the case of the bell-animal-

ON COLLECTING AND EXAMINING.

247

cule, in which there is a very strong rotary current,
in comparison to the size of the animal, this method
will greatly enhance the beauty and interest of the
object. It is a kind of temporary staining for which,
by-the-by, the aniline colours are not available, as
they are too diffusive, and, moreover, soon kill the
animals.
The activity of some of the animals is a great
obstacle to their close examination. It has been
recommended to thicken the fluid by means of some
such an addition as gum-water, so as to limit this
motion, but we fear this would not be a very successful
method. There is an article of apparatus which accompanies the microscope, called a compressorium,
which is of more practical use. It is a kind of box
in which the object is compressed between two plates
of glass, and in the most improved form of compressorium the amount of compression may be regulated
in a definite manner, so as to avoid the catastrophe
of compressing to the point of rupture. It will hardly
be possible to examine such erratic objects as waterfleas and cyclops without some such method is resorted to. With an active cyclops twisting up and
down, and jerking in all directions, it would be impossible to count the joints in the antennae, until by
some means an effectual check is put upon its skipping
propensity. It is quite possible to dissolve out the
contents of these creatures when dead, and thus
secure good permanent preparations.
Finally, what method is best to be adopted for
obtaining the largest amount of instruction as well
as of satisfactory recreation from the study of pond

248

PONDS AND DITCHES.

life ? It is, and always has been, a favourite crotchet
with us to recommend strongly concentration. To
concentrate the attention and interest as much as
possible to certain definite objects, or class of objects,
and not attempt to know or understand everything
at once. We have seen in times past how the persistent application of one person to the study of a
single insect has been productive of the most marvellous results. We would advise any one in search
of recreative occupation to make a careful selection
of the kind of objects most available, or having the
greatest attraction. Thereafter, let it be the first
object of such an one to study and examine, and
exhaust, if possible, the history of such an animal,
or group of animals or plants. Whether the selection
be in favour of Desmids, or Infusoria, or Water-fleas,
or Wheel-bearers, it matters not, but unless the area
is so circumscribed no sound knowledge can be obtained, nothing but an empirical acquaintance with
a lot of hard names. When once a selection is made,
a series of experiences will commence, as to their
homes and haunts, how they are best obtained, perhaps how they are to be domesticated or cultivated ;
and then will follow a series of observations upon
their habits, modes of life, foes and friends, food,
and methods of increase, and light will begin to dawn
upon some of their uses as links in the great chain
by which nature is united to nature's God. It is by
such method in study, and by method only, that
study will bring its reward in the satisfaction of
having spent so many hours in recreation not wholly
in vain.

ON COLLECTING AND EXAMINING.

249

We might quote from Bacon, and, indeed, from
authors innumerable, on the advantages which result
from method in studies of whatever kind, but this
is needless, since it is universally admitted that all
useful study is methodic. The course which we have
suggested has also the advantage of circumscribing
the amount of reading necessary to epitomize all the
known facts and keep the worker abreast of the discoveries of the age. This assumes that it is intended
to acquire complete mastery of the subject selected ;
and is this not also a commendable purpose ? It is
a good principle to propose to one's self a high aim,
even should it never be attained. Perfectly satisfied
that only a very few would make any effort to realize
such a student as we have indicated, it is nevertheless
our duty to speak that which is on our mind. And
now, whether skimming on the surface, or delving
deeper in order to comprehend the mysteries of
minute life, we leave our whilom companion to
wander and ponder in search of truth, and think on
Him to whom
" All acts are equal; for no more
It costs Omnipotence to build a world,
And set a sun amidst the firmament,
Than mould a dew-drop, and light up its gem."

(

25I

>

INDEX,

Page
Page
24
Achlya prolifera
48 Callitriche verna
96
Actinophrys
103 Campylodiscus
202
Alcyonella
142 Canthocamptus
203
Alisma plantago
19 Castor
32
American water-weed
21 Catabrosa aquatica
33
Amoeba, species of ... 101, 243 Cat's tail
Anacharis alsinastrum
21 Ceratophyllum ... 24, 158, 170
39
Anguillidae
181 Characece
Aquatic larvse
207 ChcBtophora endivcefolia ... 56
7*
Argyroneta aquatica
186 Closterium
97
Arrowhead
20 Cocconeis
97
Aulosloma
175, 176 Cocconema
Coleps hirtus
115
Collecting objects
234
Batrachospermum
58
Cloceochete scutata
56
Bell animalcules
107
Common Reed
, 29
Blackweed
33
Common Rotifer
164
Bogmoss
43
Conferva
49
Brachionus
163
Conjugation
51, 73
Bu Ibochcete
60
Conochilus volvox
156, 157
Bulrush
34
Cordylophora
129
Bur-reed
33
Corethra plumicornis
208
Butomus umbellatus
20 Corixa sahlbergi
231
Cosmarium
77
Caddis worms
224 Cristate/la muccdo
134

252

PONDS AND DITCHES.

Page
Cyclops, species of ... 1 9 9 , 2 4 1 Fossil diatoms
CyprtSj species of
203 Fredericella
Fresh-water Algae
Daphnia, species of
195 Fresh-water polyzoa
Desmidiacea
69
Diaptomus castor
202, 203 Gemmules
Glossiphonia tess ellata
Diatoms
83
Glyceria, species of
Diffiugla
104
Gnats
Dinocharis, species of
170
Diplodontus
189 Green hydra
Dolomedes
fimbriatus
188 Gyrinus natator
D r a g for collecting
236
Dragon-flies
219
Draparnaldia,
species of...
55
Duckweed...
25
Dytiscus marginalis
227

118
190

February excursion
Fish mould
Flight of insects
Floscularia
Flote grass
Flowering plants
Flowerless plants

240
48
223
152
31
15
36

iof
17^
3]
212
12^
22c

Hemiptera or bugs
Hippuris vulgaris
Hirudo medicinalis
Hcemopsis
H o r n wort
Horseleeches
175,
Hyalotheca
Hydra, species of
Hydrodictyon utriculatum
Hypnum, species of

Eight-eyed leech
177
Empusa musccz
48
Enormous families
201
Entomostraca
194, 201
Eosphora
160
Epistylis
109 Infusoria
Euastrum
75
Euglena,
species of, 112, 115, Isoetes, species of
243
Euplotes charon
Eylazs, mite

Pag<
84
141
4c
13:

22c
25
175
175
25
176
7c
122
6c
42
105

37» 3^

Jerkers

lie

Lacinularia

15^

Leeches and worms
174
Lemna, species of
26
Limnephilus, species of, 225, 226
Limnobates stagnorum
231
Lophopus crystallinus
13:
Low-life (protozoa)
9c
Lycosa
185, 18;
Lyngbya
54

INDEX.

2

Page

Page

53

38
Mare's tail
24 Pilularia globulifera
Mastigocerca carinata
169 Pinnularia, species of 93, 94
187
Melicerta
154 Piratic spider
163
Mesocarpus
5 2 Pitcher rotifers
179
Metopedia acuminata
167 Planarian worms
95
Micrasterias
... 76 j Pleurosigma
143
Microscope, The
238 Plumatella, species of
171
Minute crustaceans
193 Polyarthra platyptera
179
Mosquitoes
214 Polycelis nigra
132
Myriophyllum spicatum 24, 151 Polyzoa, freshwater
Pond mite
190
22
Naucoris cimicoides
231 Pond weed
22
JVavicula, species of ... 91,92 Potamogeton densum...
22
Nematoid worms
1S1 Potamogeton natans
Nephelis oc toculata
17 7 Preservation of objects ... 245
I
101
Nitella
41 Proteus
119
Norfolk " b r o a d s "
28 Ptyxidium ovulum
JVotommata
161 |
37
Nuphar lutea
17 Quillwort
Nymplicea alba
17
Ramatra linearis
230
17
CEdogoniacetz
... 59 Ranunculus aquatilis
180
Oscillaria
61 Red-worms
Reedmace
33
29
Paludicella
146 Reeds and rushes
172
Pandorina morum
64 Revival of rotifers
fluitans
46
Paramecium aurelia
i l l Riccia
47
Parasites in vol vox
161 Riccia natans
166
Parasitic larvce
216 Rosy philodina
148
Penium
77 Rotifers
164, 165
Phantom larva
208 Rotifer vulgaris
Philodina roseola
166
20
Phragmites communis
28 Sagittal ia sagittifolia
52
Phryganea, species of
225 Saprolegnia
34
Phyllactidium
57 Scirpus lacustris
170
Pillwort, or pepper grass... 38 Skeleton wheel-bearer

PONDS AND DITCHES.

254

Spargamum, species of ... 33
Sphagnum, species of
42, 46
Spiders
187
Spirogyra
5°
Spirotcenia
78
Sponges, fresh water
105
Spongil/a, species of
105
Starwort
24
Statoblasts
135
Stauroneis phcenicenteron... 95
Stentor Mulleri
no
Stephanoceros
149
Still waters
7
Stylonichia
117
Sun animalcule
103
Surirella, species of
96
SynchcBta
161
Synedra, species of ... 95, 96
Tardigrades
Trachelitis
Trilobus pellucidus
Tubifex rivulorum
Typha, species of
Ulothrix

Page
Vaulter
202
Velia currens
231
Villarsia nymphceoides
18
Volvox globator
61
Vorticella, species of... 107, 242

Water-bears
Water-beetle
Water-crowfoot
Water-fleas
Waterlilies
Water milfoil
Water mites
Water-mosses
Water net
Water plantain
Water spiders
Water Villarsia
Water whorl-grass
Wheel animalcule
191
Whiptail
112 Whirligig beetle
, 183 Wolffia arrhiza
180
33 Zoospores
Zygnema
53 Zygogonium

191
227
16
193
17
24
189
42
65
19
185
18
32
164
169
229
28
52, 53, 74
51
52

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