m NORTH CAROLINA STATE UNIVERSITY LIBRARIES S02 174637 U This book is due on the date indicated below and is subject to an overdue fine as posted at the circulation desk. EXCEPTION: Date due will be earlier if this item is RECALLED. 150M/01 -92-941 680 PROBLEMS, PROJECTS, AND EXPERIMENTS IN BIOLOGY ATWOOD BY THE SAME AUTHOR CIVIC AND ECONOMIC BIOLOGY "This latest addition to civic biology offers a new viewpoint in science teaching, and in giving prom- inence to the practical phases of the science" — General Science Quarterly (Mass.) COMPARATIVE VERTEBRATE DISSECTION This volume is the result of many requests from teachers for a manual "different" from those now in use. The book prepares the student for a continua- tion of the study to its logical conclusion in uni- versity courses. P. BLAKISTON'S SON & CO. PHILADELPHIA PROBLEMS, PROJECTS, AND EXPERIMENTS IN BIOLOGY BY WM. H. ATWOOD, M. A., M. S. MILWAUKEE STATE NORMAL SCHOOL 55 ILLUSTRATIOxNS PHILADELPHIA P. BLAKISTON'S SON & CO 1012 WALNUT STREET ^ .c^ Copyright, 1923 by P. Blakistox's Son & Co. PRINTED IN U. S. A. . BY THE MAPLE PRESS YORK PA n> C. State Cof/eg FOREWORD TO TEACHERS AND STUDENTl The contents of this manual are arranged to correspond In sequence with the author's Civic and Economic Biology, but it has been assembled with the thought in mind thai it may be used with other texts. If copies of Civic and Economic Biology arc available as references, this manual should be adapted to any course in biology, either with or without a special text. With this in mind, referent to various biological works have been placed below the sectional headings. It is the author's hope that the references cited will be available to the students in the laboratory. Laboratory work is naturally so dependent upon conditions which obtain, both within the laboratory and in the environment of tin- school, that it is best to have a considerable variety of exercis suggested from which selections may be made. It is hardly to be expected that all of the exercises suggested here will be worked out, or that they will be taken up, in all cases, in the order given. They are all workable, and something of value may be learned from each. Experiments which often fail, or give indifferent results, have been eliminated. Those which have been selected should stimulate thought. A problem requires thought for its solution. Class spirit and cooperation are stimulated if student commits are appointed or elected to assist the instructor. Student- should feel that they are as reponsible for the success oi the course as the teacher. The membership of the committee- should be changed from time to time so that each student will serve in a variety oi activities. If the class is well organized, a diversity of work may go on at one time; but under unfavorable condition- it will be more necessary to keep all members working at the same problem at a given time. Variation in the content and method has been especially sought. Students soon lose interest in a drawing course, or a laboratory course in essay writing. Teachers also enjoy a course more it it can be made to varv in method and content from year to J 'W« J* ) vi FOREWORD TO TEACHERS AND STUDENTS There should be a difference between a problem, a project, and an experiment; but the difference is more in the point of view of the student and teacher than in the exercise itself. Do not make experiments of mere demonstrations. It is not necessary that all things be taught by the problem method. Simple things should be simply taught. The directions are stated very briefly. The student should be given an opportunity to make mistakes. They should have an educational value. Directions which are given in too great detail eliminate opportunity for initiative. Students should ask few questions of the teacher and should solve their own problems. Quizzes should be frequent and should cover all reports, topics, demonstrations, field trips, etc. A quiz is a review. Everything should be reviewed. Students are responsible in the quiz for the projects of others which have been presented to the class. Experi- ence has shown that students study better if quizzes are frequent and searching. Written work should be handed in daily, as it is ready, and that which fails to equal the standard of the course should be rewritten. Teachers and committees should return students' papers promptly. Advance preparation should be made for many laboratory problems and projects. Look ahead in the manual and make arrangements for such exercises. Seedlings require from two to three weeks to sprout and start their growth. Paramecia cultures should be started about two weeks before they are to be used. Some materials which can be collected in the fall for winter use should be carefully preserved. Reports and topics should be assigned in advance and should be ready when the study with w r hich they are connected is before the class. The illustrations have been selected with great care as to their teaching value and also for their scientific accuracy and artistic qualities. Good illustrations are a stimulus to the student. Those which have been borrowed are credited in the legends. It is the hope of the author that the use of this manual will ensure both enjoyment and efficiency to the courses in the biological sciences where it is used. Wm. H. At wood. TABLE OF CONTENTS Pace i ORGANIZATION , 2 INORGANIC MATTER 2 3. CHARACTERISTICS OF LIVING MATTER 4. ENVIRONMENT AND ADAPTATION 4 5. THE GOLDENROD, A TYPICAL PLANT 6. INSECT STUDY 6 7. THE CRAYFISH (CRAWFISH) id 8. WORK WITH ROOTS AND SOILS 14 9. PLANT STEMS AND FORESTRY 10. THE STRUCTURE AND WORK OF LEAVES 23 11. FOOD AND ITS USES 12. CHEMICAL FOOD TESTS 13. DIGESTION 36 14. RESPIRATION AND CIRCULATION 39 15. TROPISMS AND RESPONSES 41 16. STUDIES OF PROTOZOANS 45 17. LESSONS WITH ALG^, MOSSES, AND FERNS 4 7 18. THE LIFE HISTORY OF THE PINE TREE 19. THE PARTS AND FUNCTIONS OF THE FLOWER 50 20. CELL DIVISION ai. THE LIFE HISTORY OF FLOWERING PLANTS 22. FRUITS AND SEED DISTRIBUTION 23. STUDIES IN PLANT PROPAGATION 24. SEEDS AND SEED GERMINATION 6a 25. LIFE HISTORIES OF ANIMALS 26. THE FROG 27. STUDIES ON THE ECONOMIC IMPORTANT I <>l DOMLsri- CATED ANIMALS AND PLANTS 28. VARIATION AND HEREDITY AND THEIR APPLICATION I PLANT AND ANIMAL BREEDING 29. EUGENICS AND EUTHENICS vii Vlll TABLE OF CONTENTS Page 30. THE DOCTRINE OF EVOLUTION 78 31. BACTERIA, YEASTS, AND MOLDS 79 32. BACTERIA AND CONTAGIOUS DISEASES OF MAN 84 33. CONTAGIOUS DISEASES OF PLANTS 87 34. WEEDS 88 35. PARASITIC WORMS 89 36. INSECT PESTS 90 37. RATS AND MICE 94 38. FISH AND POND LIFE 95 39. THE PERCH (DISSECTION) 96 40. BTRDS 98 PROBLEMS, PROJECTS AND EXPERIMENTS IN BIOLOGY i. ORGANIZATION References Civic and Economic Biology, Atwood, Preface and Study i. Civic Biology, Hodge and Dawson, Chaps. I and IT. Elementary Biology, Gruenberg, Preface and Chap. I. Biology for Beginners, Moon, Chap. I. Hunter's Biologies, Preface and Chap. I. The Teaching of Biology, Lloyd and Bigelovv. Principles of Science Teaching, Twiss, Macmillan Co. The Teaching Botanist, Ganong, Macmillan Co. I. Soon after the beginning of the school year, it will he well to hold an election and choose committees to attend to the business of the class. The library committee should have charge of tin- books and the bookcase. A good system of cataloguing should be insti- tuted, and every book should always be in its place at the dose of the day. The archives committee should have charge of all paper- and reports which are produced by the members of the das The museum committee should have charge of the museum cases and should see that all specimens are kept in good order. The committee in charge of apparatus should see that the equipment which belongs to the department of biology is conserved and put away in u r ""d order. The supplies committee should purchase for the instructor such materials as are to be bought locally and should keep the materials used in the course in good order. The committee on ventilation and sanitation should assist the instructor in such matters as lighting, fresh air, heating, cleanliness, etc. There should he Min- or more committees in charge of the plants and animals which a kept alive in the department. Are there any other commitl which should be appointed? Remember that Loyalty t<> duty and a wholesome spirit of cooperation are the prime essentials which i 2 PROJECTS AND EXPERIMENTS IN BIOLOGY make for a successful course in biology. The class expects every one to do his duty promptly. 2. INORGANIC MATTER References Civic and Economic Biology, Atvvood, Study i. Introductory chapters of other biologies. 2. Exhibit of Kinds of Matter.— The supplies committee should arrange an exhibit of chemical elements, chemical compounds, and minerals. Place them in three groups and label each specimen. Make such remarks to the class as may seem appropriate, and have the names of the specimens learned by the students. Prepare another similar exhibit of carbohydrates, fats, and proteins. Understand that the chemical composition of living things and their products is much more complex than that of minerals. 3. Crystallization. — Heat about a half cupful of water to boiling and add as much copper sulphate as will dissolve in the boiling water. Pour the liquid into a dish and let it cool. Watch the formation of crystals of copper sulphate. Dissolve some more copper sulphate in warm water and put it away to evaporate slowly. The crystals which form in this way should be larger. Why? Try to get crystals of the following by this method: ammonium nitrate, sugar, salt, glucose, starch, glue, potassium sulphate, potassium chlorate, and potassium dichromate. Each student should not try all of the above mentioned materials, but if each takes one, results may be compared. Do they all form crystals? Are the crystals of each salt alike? 4. Draw diagrams of some of the crystals. 5. Irritability. — Pour a small amount of a solution of silver nitrate into each of four test tubes. To the first add some sodium chloride solution. To the second add some sodium bromide solution. To the third add some sodium iodide solution, and leave the fourth as it is. Place them in the sunlight. How long does it take to change the color? 6. Report. — Some student may prepare a topic on the subject, The Chemical Changes Produced by Light on Silver Salts. See a chemistry, or a book on photography. CHARACTERISTICS OF LIVING MATTER 3. CHARACTERISTICS OF LIVING MATTER See the same references as in the preceding se< tion. 7. Growth. — Committees or individuals may study some of the following phenomena of growth and report to the clas How rapidly do leaves come out of the hud? In what ways are various leaves and flowers folded in buds? Do stems grow in length after they are once ^_^___„_____ formed? How do they in- iff crease their diameters, by adding to the outside or throughout the entire stem? Do leaves reach a certain size and then stop growing? Is the color of young leaves lighter or darker than old ones? Which plants grow the more rapidly, vines or plants with heavy stems? 8. Plant some seeds and note the growth of the roots. Do they increase in diameter? Do they grow only at the tips, or throughout their entire length? In a young seedling, are the roots or the leaves the more extensive? 9. How long does it take the following animals to be- come fully grown: fly, potato beetle, snake, turtle, cow, sheep, dog, chicken, robin, man, elephant ' J How long does it take the eggs of the following bird- to hate li : robin. chicken, duck? Compare the proportions of the parts of a young dog with those an old one. How do they change as the puppy becomes a dog? 10. Irritability. — If a specimen of Mimosa is growing in the labora- tory, touch its leaves and note how they respond. It no plant is Fig. 1. — Diagram of a chamber to phototn>i>ism. {Fundamental Gager.) 4 PROJECTS AND EXPERIMENTS IN BIOLOGY available, plant some seeds and have one ready for observation later. Place a young, rapidly growing weed, or some other plant, in a dark box with light admitted through only one side. After a few davs note its response to light. Observe the leaves of the plants in the windows and other places. How are their leaves arranged in reference to the light? Can a committee find a compass plant and bring it into the labora- tory as an exhibit. Explain to the class just how it grew. Let a committee experiment with earthworms to find if they respond to light. Do they respond to a jar? To sound? Touch one with a drop of water, then with salt water, then with a weak acid. Compare results. Touch first the head and then the tail with a toothpick and determine which end is the more sensitive. Place one on a moist blotter on a dry board. Will it crawl off of the blot- ter? Is it sensitive to dry surfaces? Report all of these results to the class. Some of them may be repeated in the presence of the class. Other experiments on the responses of plants and animals will be performed later in the course. 4. ENVIRONMENT AND ADAPTATION References Civic and Economic Biology, Atwood, Studies 2, 3, and 4. Civic Biology, Hunter, Chaps. II and III. 11. Field Trip. — The class should be divided into troops of three to six students each for the study of the various features of the environment in the vicinity of the school. One group may study a meadow, another a brook, another a pond, and another a woods. Make out a plan of what you expect to study before you start. Never go on a field trip without a notebook. Keep a record of what you find. Note the conditions of light, heat, moisture, abundance of plants and animals, soil, and the kinds of life found in each region. Bring samples and specimens to the laboratory for exhibition and discussion on the day following the excursion. Write lists on the THE GOLDENROD - board of the kinds of plants and animals found in ea< li lo( alii y and compare. Do not wear your best clothing on field trips. I sped to gel your feet muddy. Those who visit a pond or brook should ha to secure the small animals which live there. Water-tight \ should be provided to bring home the catch. Bags and baskets will be convenient. 12. Project— Let each student of the class choose a plant or animal and make a special study of its relation to temperature, water. light, air, soil, food, and shelter. The results should be written up and filed with the archives committee. Sonic of the- m< interesting ones should be read to the class. 5. THE GOLDENROD, A TYPICAL PLANT References Civic and Economic Biology, Atwood, Study 5 and Fig. 1 76. Wild Flowers, Blanchan, Doubleday, Page & Co. 13. Field Trip. — Read Study 5 in Atwood 's Biology, and make arrangements to go on a field trip to study the goldenrod or some other typical plant. Where do they grow? What kind of soil? What arc tin- light and moisture conditions of their habitat? What other plant- u r row with them? Are they more or less vigorous than their competitoi Are they more or less numerous than all of the other kind- iA plants in their vicinity? How do they compare in this respect with any one kind? How do they rank in abundance as compared with each of the other kinds of plants growing with them? How tall is the highest plant which you can find? What gave it this advantage? Does it bear more seeds than the othei What is the average height of goldcnrods? Compare them with other plants in their environment in this respect. Note the color of the flowers. Estimate the Dumber ^\ individual blossoms in a large and an average sized flower cluster. 1 some have gone to seed, count the number of seeds to a flower and to a duster. Scatter some seeds in the wind and watch them -ail. !»«• they sail 6 PROJECTS AND EXPERIMENTS IN BIOLOGY as well as the dandelion seeds? What is the advantage in having the blossoms in a cluster? Note how tall the stems are. Are they branched? Why would it be poor economy to have them branched at the bottom? How are the leaves arranged on the stem? Where are the ones which are dying? Why do they die first? Note the shape of the leaves. Does each get relatively more light than it would if they were broad and large? Does this same principle hold for blades of grass? Find a plant which is growing in loose soil and dig it up. Find its underground stems and its roots. What is the color of each? Are there any scales on the stems? What are the scales morpholog- ically? Do you think much food could be stored underground? How many plants would have grown from the one which you dug out the next spring? What is the use of the underground stem? Capture as many of the various insects inhabiting the goldenrod as you can. There will be beetles, bees, flies, and butterflies. Assign them to one of these groups. Have a separate receptacle for each group and take them to the laboratory where students may find what their names are as a project. What were the insects doing on the goldenrod? Are any of them of any benefit to the plant? Bring some goldenrod and other plants to the class-room for reference during the quiz which follows the field trip. 6. INSECT STUDY References College Zoology, Hegner, Macmillan & Co. General Zoology, Pearse, Henry Holt & Co. Civic and Economic Biology, Atwood, Studies 6, 64, 65, and 66. 14. Laboratory Work.- -The grasshopper is the largest of the common insects, and it is of a generalized type of structure. These facts, together with its abundance, make it a favorite for laboratory study as a typical insect. If the natural history of the insect is to be studied, the bee is considered superior. See Atwood's Biology, Study 6, also pp. 411 and 412. Large lubber grasshoppers may be had from the dealers, or smaller ones may be caught locally. INSEC1 STUDY Make a sketch of the side view of the grasshopper to show the features mentioned below. The body of an insect is divided into three divisions —the head, thorax, and abdomen, bind the lai compound eyes. Examine them with a lens to the facet Can the grasshopper see in all directions at one time withoul movi his head? The three simple eyes will be seen with the aid of a lei One is in the middle of the face, and another before ea< h compound eye. They appear as small beads. The antennae are possessed of how many joints How great is their range of movement? Wd ^ ATAX obd omen • compound e^e ocellus | /pronotum j auditory or^an "tarsus Fig. 2. — External view of a grasshopper to show its parts. [ftet WaU Connecticut Geological and Natural History Survey. Bulletin No. '■ The mouth parts are shown here and in Figs. 328 and 329 in Atwood's Biology. Find them in your specimen and learn the names of their parts. They may be arranged as in Fig, 329 and drawn. The thorax is composed of three parts (somites The first i> called the collar. It is movable on the body. Note that it bears the first pair of legs. The second division bears a pair of wings and a pair of legs as does the third. The divisions ,,|' the thorax are called the prothorax, mesothorax, and metathorax. 8 PROJECTS AND EXPERIMENTS IN BIOLOGY Compare the two pairs of wings. Which pair does the most of the flying? How does the grasshopper make its sounds? Do you know how the katydid, cricket, and cicada make their sounds? Study the leg of an insect. The first two parts are small and difficult to make out. They are the coxa and trochanter. The femur is the largest part of the leg. It is followed by the slender tibia, and the foot is the tarsus. Compare the legs of the grasshopper with those of other insects. Draw an insects' leg and label the parts. The abdomen is composed of rings (somites). How many are there? The first ring is incom- plete below in the grasshopper and contains the ear. See Fig. 121 in Atwood's Biology. 15. Report. — How does the ear of the grass- hopper work? If a live specimen is available, its respiration should be observed. The abdomen will be seen to swell and contract as air is taken into the tracheal system and let out again. See Figs. 33 and 96 in Atwood's Biology. Count the spiracles along each side of the abdomen. You should be able to find- two on each side of the thorax also. An ovopositor consisting of two or more spines is usually found at the end of the abdomen of female insects. 16. Report. — How do grasshoppers lay their Fig. 3. — Mouth parts of a grass- hopper, m, Man- dible; max, max- illa; L, labium; p, palps. (Elements of Animal Biology, Holmes.) eggs 17. If it is desired to study the internal anatomy of an insect, a committee may be asked to find suitable directions in a manual and copy them on the board. 18. Exhibit. — The museum committee may prepare an exhibit to show one or more insects of each of the common orders of the class Insecta. Notes which state the differences which distinguish the orders may be made to accompany the exhibit. The notations will be somewhat like the following table: [NSECT STUDY Fig. 4. — The internal anatomy of the grasshopper. The regions of th are: hd, Head; th, thorax; and ab, abdomen. The regions of tin- tract are: tn, Mouth; oe, esophagus; p, pouch; g, gizzard; 1 s, stomach; i, ileum; c, colon; and r, rectum. Other parts arc: .;. Anteni b, brain; ce, cement gland; d, duct of salivary glands; t, ex tubuli h, heart; o, oviduct; ov, ovaries; sg, salivary glands; vg, ventral ganglia of m system; w, wall of body. (Elementary Zoology, Galloway.) Fig. 5. — Cross section of the body of the ap, First joint of leg; bw, body-wall which is made up muscles; c, gastric caeca; /*. heart; /. pa 1 ; of body-cavity; ph. 1-3, tracheal tubes; sg, salivary gland ventral | mentary Zoology, Galloway.) IO PROJECTS AND EXPERIMENTS IN BIOLOGY Aptera : >il\ ir fish; no wings, body covered with scales. Ephemerida: May-flies; delicate four winged flies, two or three setae project from the end of the body. Odonata: dragon-flies and damsel-flies; four winged, long bodied insects. Orthoptera: grasshoppers, crickets, roaches, katydids, walking-sticks, and mantids; chewing mouth parts, straight wings. Hemiptera: bugs, cicadas, scale insects; piercing mouth parts. Lepidoptera : butterflies and moths; large scaly wings. Diptera: flies and mosquitoes; only one pair of wings. Hymenoptera: ants, bees, wasps, and ichneumon-flies; wings hooked together. The best reference for this work is General Zoology, Pearse, Henry Holt and Co. 7. THE CRAYFISH (CRAWFISH) References Civic and Economic Biology, Atwood, pp. 30, 13S, and 142. General Zoology, Linville and Kelly, Ginn & Cc. Practical Zoology, Hegner, Macmillan Co. Biology for Beginners, Moon, Chap. XXII. Civic Biology, Hodge and Dawson, Chap. XXVI. New Essentials of Biology, Hunter, Chap. XVIII. The laboratory work on the crayfish is given at this place in the manual, but the needs of the course may require that it be studied elsewhere. No large amount of space was given to this form in Atwood 's Biology because it can be studied satisfactorily in the laboratory, and it is of little economic and civic value. Ho vever, it has long been a favorite for laboratory dissection. Crayfish may be taken from the ponds and brooks where they live by fastening a piece of fat meat on the end of a string and casting it into the water. When the animal seizes the meat, it may be drawn from the water before it has time to "think it over" and let loose of the bait. They may be had, alive or preserved, from the dealers. The lobster is better for dissection, because it is larger. 19. The live crayfish may be kept in shallow water in the labora- tory indefinitely. They should be fed pieces of meat and bread. Why must they be kept in shallow water? Must they be allowed an opportunity to come to the surface? Why do they come to the surface? How do they seize their food? How is it held while it is being eaten? How does the crayfish walk? Which legs push and which pull? Are the pinchers used in walking? How many legs are there? Do they all have claws on their ends? Compare the legs THE CRAYFISH j , with those of the grasshopper. Note how the feelers are used. How many are there? The smaller ones arc called antennules, and the larger are called antennae. Find the eyes. Can they be moved? Find the large fin-like structure at the end of the tail. Thro* crayfish in a vessel of deep water and learn how it swims. I >es4 ribe the process. Does the crayfish prefer to hide under something oc to remain out in the open? Take one out of the water and pla< e it on the desk. How does it retreat? How docs it make a defei when retreat is not possible? With a piece of glass tubing fon e some red ink or other colored solution into the water near the head of the crayfish. Note by this how the water circulates through the gill chambers on the sides of the body. Watch the swirnrnerets in their rhythmical movements under the abdomen (tail). The dead crayfish will be colored red if it is preserved in formalin. What are the natural colors of crayfish? Are they all of the same color? Are their colors protective? Note the two body divisions in the dead specimen. The head and thorax are combined in one piece, called the cephalothorax. The part commonly called the tail is the abdomen. The mouth parts are more numerous than in the insects. The first pair are hard and are called the mandibles. The second and third pair art- called the first and second maxillae respectively. The three pairs which follow are called maxillipeds. There are. then. >i\ pair- of appendages which have to do with eating, but the posterior pair- are not of so much importance as the anterior on< Tin- posterior pairs also help in passing water over the u r ill<. Remove the mouth parts and place them in a series on a sheet of paper. When they are arranged have them inspected. It they are all perfect, th< should be drawn and labeled. Not all students will succeed in get- ting all of the parts out entire. They should be removed with the greatest care with sharp pointed tweezers. Draw a cheliped, a leg, a swimmeret, ami the telson. The crayfish is a somited animal. Count the rings in theabdonu The telson may or may not be counted, a- you like. Are then- evidences of segmentation in the cephalothonu Dissect the animal by opening the -hell (carapace- on the back and cutting it away. The stomach is a lame sac in the head end 1 2 PROJECTS AND EXPERIMENTS IN BIOLOGY the body. Cut it open and find the "teeth" which it contains. What are they used for? Just back of the stomach is the heart. It is a mere sac with muscular walls. On the sides of the stomach and heart are the reproductive organs. Nearer the legs and also on the sides of the stomach are the halves of the pancreas. This is a large glandular organ which secretes digestive juices. The green glands are situated below the stomach on either side of the head. I The glands are not always green.) They are excretory and dis- charge their fluid through openings in the bases of the antennae. Trace the intestine through the abdomen and note the strong muscles through which it runs. Fk;. 6. — Internal anatomy of the crayfish, a 1 , a 2 , Antennae; br, brain; d.l., duct of liver or pancreas; e, eye; g, green gland with opening at g 1 ; h, heart; /, intestine; I, liver; m, mouth; ms, muscles; p, pericardium; r, rostrum; s, stom- ach; sa, sternal artery; v.n., ventral nerve cord. {From Hatschek and Cori.) Draw a diagram of the internal anatomy of the crayfish. Make the drawing very light at first and have it inspected before finishing it. Label it completely. It is sometimes advisable for students who have had little experience in drawing to use a stencil or some other device to get a perfect outline of the body in which to draw the visceral organs. The blood vessels need not be looked for unless the specimens have been injected. The nervous system will be found by removing the other structures in the cavity of the body and looking first in the head between the eyes where the brain may be seen. What is its color and shape? Show it to the instructor. Commissures run back from it to the ventral ganglia going on either side of the esopha- THE CRAYFISH gus. Carefully dissect the tissues of the floor of the cephalothi and as you do so, trace the nerve cord hack to the tail. Noti ; it is a double row of ganglia. Is there a double ganglion for ea< h somite? See figure 95 in Atwoods' Biology and note the nerve cord of the earthworm. The crayfish has the same tyjx grasshopper and all other arthropods. I Fig. 7. — Diagramatic cross section through the thora <;. Appendage; c, carapace; c.f., flap of the carapace overhanginj tive tract; g, gills; h, heart; /, liver or pan m, m', muscli ps. space around the heart (pericardium) ; r, reproductive bodies; ■>!, • I v.a., ventral artery; v. s., ventral blood sinus around the nei AfUt ! :ng. Elementary Zoology, Galloway.) The gills of the crayfish lie in a row along the sides of the cephalo- thorax without the body-cavity bu1 within the cover of the carapa< They have three different attachments and are in -< and three for each somite. Can you determine where the} attached and which somites have three u r ills and which The ear of the crayfish is to be found in t he base i >l 1 1 •■ nnule of each side. It is shown in V'\^. [ig of Atwood' B and i-> more properly called a statocyst. Why? Cut it open and examii the interior. The pit lure was made from the lobster. U differ from the statocyst of the crayfish? 14 PROJECTS AND EXPERIMENTS IN BIOLOGY 20. Project.- -Try to keep some crayfish alive in the laboratory. They should be in charge of a student or committee, and should be ivd twice a week or oftener. Do not permit stale food to remain in their water. Provide something for them to hide under. 8. WORK WITH ROOTS AND SOILS Reference Civic and Economic Biology, Atwood, Studies 7 and 8. 21. Supplies Committee Project. — Secure samples of various kinds of roots to show to the class. Try to get brace roots of corn; aerial roots of ivy; tap roots of weeds, turnip, radish, carrot, beet, parsnip, alfalfa; fascicled roots of dahlia, and sweet potato; and j>\ar vascular -smaii-ceiiea parenchyma large-celled parenchyma -nng of growth Fig. 8. — Diagramatic cross section of beet. {Botany of Crop Plants, Robbins.) fibrous roots of various grasses and grains. As each specimen is presented to the class such points of interest as are known may be mentioned. Drawings may be made of some of them. 22. Project.- -Two boys may secure a draw-scale and go out and pull up various weeds with it attached to their stems and note what force is necessary to remove them from their anchorages. A large scale will be necessary if you remove big weeds. Bring the weeds and the record before the class. 23. Laboratory Work. — Each student may be provided with sections of the carrot, beet, and other roots. Find the epidermis, ROOTS AND SOILS I 5 cortex, and stele. Note how the branch roots « ome off from the stele. Scrape some of the tissue of the carrot stem and examine under a compound microscope to find the various kinds of cells, especially the spirals of the sap ducts, of which the root is composed. Draw a cross section of the root and label all of the parts. 24. Plate Gardens. — Some of the students may prepare some glasi plates and pieces of blotter of the same size as the plates and plant small seeds on the surface of the blotter. Then place a glass plate on either side of the blotter and tie a string around them. Dip the plates and blotter in water and keep in a covered dish to prevent - cortex "H- cambium pah and wood Fig. q. — Diagramatic cross section of turnip, (Botany oj ( rup Plant R evaporation. As the seeds grow the root hairs are seen. Plant different kinds of seeds in each garden. Note. — Radish seeds arc very easily germinated and develop r.»<>t hair- which are of the best quality for observation. It' -prays of tin- wanderii cantia) are placed in water, they will develop excellent r.n.t hair- and tip- 25. Acid secretion of roots may be shown by !rtt : < spread their roots in soil over the surface of polished marble -lab- or blocks. After some weeks they should be taken up and the si cleaned, when a delicate etching may be seen on 1 he polished surl Another method is to prepare a fluid (thin) solution of gelatin and litmus. Add enough soda to make it slightly alkaline. Place it in a test tube and insert the roots of a seedling. Where the n i6 PROJECTS AND EXPERIMENTS IN BIOLOGY secrete acid the litmus will turn red. Care must be taken to avoid the growth of bacteria before the demonstration is complete. 26. Individual Project. — Some of the students may plant the seeds of squash or pumpkin in sand. When the seedlings are the size shown in Fig. 45, Atwood's Biology, they may be pulled up if the sand has been allowed to become nearly dry, and the root hairs will hold the particles of sand as shown in the figure. Show your results to the class. This may be tried with other kinds of seeds. What is the value of root hairs to the plant? 27. Osmosis Experiments. — Prepare an egg osmometer by making an opening in the top of an egg large enough to insert a glass tube of small diameter. Insert the tube and seal with paraffin or sealing wax. Now carefully chip away the shell from an area as large as a dime on the other end, but do not puncture the shell membrane. Emerse the egg in water in a beaker. It is best not to let the opening in the lower side touch show osmosis through a . . . , , membrane. Sugar solu- the bottom of the glass. tion is placed within the The above experiment may be modified thistle tube and water is , ^ 5JJ . . n placed in the large vessel. as shown in Gager s Fundamentals of Botany, {Experimental General Fig. 44. A further modification is to place Science, Clute.) . . . , . . . . . . the entire egg in a weak acid solution (about 4 or 5 per cent) as the shell is dissolved off the egg membrane becomes distended until the egg is nearly spherical. 28. The carrot osmometer is made by boring a hole in the top of a carrot (or beet) with an auger and fitting a rubber stopper in the opening. If the opening is filled with a strong sugar solution and the carrot is emersed in water good results should follow. Make more than one. See Atwood's Biology, Fig. 46. 29. Cell turgor may be demonstrated by placing slices of beet in strong salt water. Why do they become flabby. Place wilted slices in water. Why do they become turgid? 30. Individual Projects — Choose two plants which are easily wilted. Allow the soil in their pots to become dry. When they ROOTS AND SOILS i ; are willed, water one pot abundantly and cut the other plant • near its root and put it in a vase of water. Whit h revives the tn< rapidly? Of how much value are the roots and their root hail 31. Soils. — The supplies committee should secure samples sand, clay, humus, and such other kinds of soils as are available and prepare an exhibit for the class. Another cxhil.it may be made to show the kinds of rocks which produce -and, clay, and lime soils when they weather. 32. Demonstration.— Hygroscopic water may be shown bypla< ing some soil in the bottom of a test tube and holding it in a horizontal position over a flame so that the soil is heated. Moisture will collect on the cool sides of the top of the tube. Compare the amount of such water in sand and humus. Is it possible that some of the water which comes from the humus is due to chemical decomposition? 33. Experiment. — The value of a mulch in conserving soil moisture may be shown by working out the experiment shown in Fig. | Atwood's Biology. 34. Capillarity may be demonstrated for soils by placing various kinds in large glass tubes (gas lamp chimneys) which have been - up in pans. The soil will lie against the bottom of the pan. Pour water into the pans and watch it rise in the soil in the tube \\ hich kinds of soil allow water to pass up the most rapidly? 35. Percolation may be demonstrated with the same apparatus is used above, but the water is poured into the top of the tube in each case. Does it pass down equally fast in all soils. What soils will receive the most rain water? 36. Project. — The humus content of soils may be demonstrated by weighing out a small amount of dried soil on a delicate balan and heating it to redness until all of the carbon of the humus is burn* out. On weighing again the difference in weight will indicate wl proportion was composed of plant and animal remains, experiment may be performed by various -indent- a- ap ' and the results presented to the 1 la--. 37. Project.— The comparative ability of soils to hold wat may be demonstrated by the experiment shown in Fij in Atwood's Biology. Place a different kind ^\ -oil in each dish and 2 l8 PROJECTS AXD EXPERIMENTS IN BIOLOGY omit tin- sawdust. Do all soils dry out with the same rapidity? Show the results to the class. 38. Topic- The fixation of nitrogen in soils by the agency of bacteria. See Fig. 21. 39. Crop Rotation. — Consult references and learn what this means. What has clover and other legumes to do with it? What would be a good rotation for a potato farm? For a farmer who specializes in wheat? In corn? In cotton? Make a diagram of each of the above mentioned rotations on the board. Discuss them in class and let each student make a copy for his notebook when they have been corrected. This may be worked out as a class pro- ject. The date of the study in class should be set two days ahead and each student should be given references in the agriculture texts in the library. 40. The value of drainage may be shown by placing plants in each of two tin cans. Make holes in one and leave the other as it is. Water them both frequently but keep the can without holes in the bottom flooded. After some days note the difference in the two plants. How long does the one without drainage live? Are all plants affected the same? How does excess water damage roots? 9. PLANT STEMS AND FORESTRY References Experimental Botany, Payne, American Book Co. Civic and Economic Biology, At wood, Studies 9, 10, and 11. 41. Field Trip. — Go to a woods or a park and study trees. Learn to recognize them by the shape of their stems and branches. Com- pare the thickness and roughness of the bark. Note also its color. Compare the twigs as to size. Collect samples of twigs to show various kinds and arrangement of buds, and bring them to the laboratory. Place some of the buds which have been collected after the leaves have fallen, in water in the warm sunlight. They will open and may be studied as to their scales, scars, leaves and flowers. PLANT STEMS AND FORESTRY [9 42. Draw specimens of bucls and label them. Se< Fig 6,and 57 in Atwood's Biology. 43. Demonstration.- -The supplies committee should sei ure sp< mens of erect, climbing, prostrate, and underground stems and present them to the class with appropriate remarks as to where if are found, how they are related to the environment of the plant, and what special advantages each provides. coro —leaf bud growth scar scales / rjrowfn Fig. ii. — Spur of sour cherry to show (lower buds. Compare with P and 57 in Atwood's Biology. (Botany 0) ( 'rop Plants, Robbin 44. Notebook Work. Prepare a table listing the advanta and disadvantages of each special kind oi stem. 45. Project. — Plant specimens of bulbs, corms, tubers, and rhizomes. Give them into the charge of a committee and obs them from time to time throughout the coming months. 46. Draw cross sections of young stems and label the r< and rings of tissues which appear. Permanent slides may be had from dealers. These may be used with the microscope or lantern. 20 PROJECTS AND EXPERIMENTS IN BIOLOGY 47. Experiment. — Investigate the circulation of sap in stems by placing various kinds in red ink. They should be in good health Fig. 12. — Section of tulip bulb to show the structure of a typical bulb. B, Flower bud; F, stem; S, bud-scales. (Fundamentals of Botany, Gagcr.) Fig. 13. — Photomicrograph of a cross section of a young stem of Aristolochia sipho to show beginning of the formation of the cambium ring, a, Epidermis; b, collenchyma; c, parenchyma of cortex and starch sheath; d, sclerenchyma; c thin-walled parenchyma of the pericycle; /, medullary ray; g, phloem; h, xylcm; i, cambium; j, pith. (Plant Anatomy, Stevens.) and growing. The ink will pass up in their sap ducts making them more easily seen. In what part of stems does the sap flow up? PLANT STEMS AND FORESTRY 2 I Draw cross sections of stems to show the region where the sap flows upward. 48. Project.— Plant portions of stems of the willow, English ivy, and other plants with their top ends in the soil and the bottom ends up. If they are well cared for they will grow this way. \\ bat influence do you think gravity has on the direction of flow of sap? Fig. 14. — Photomicrograph of a cross section <•!" a four-year-old Aristolachia sipho. Note the annual rings ami the compressed medulla The labeling is as in the previous figure with tin- following additi cambium; k, cork; m, new medullary ray forming; n , from thi xylem has been formed from the cambium. {Plant .1 mitom;. - 49. Reports and Topics.- Will the library committee prepare a list of topics on trees and forestry which are suitable for written themes or reports? The archives committee will consult with the instructor when the topics selected arc written up and el which should he given to the (lass. 50. Demonstration. Show specimens of plane and quart) sawed oak and other woods to the class ami explain the grain 22 I'ROJKCTS AND KXPERIMENTS IN BIOLOGY ..I wood. It is due both to the annual rings and the medullary rays. 51. Project. — Find some stumps of trees which have been cut recently, measure their diameters, and count their rings. How fast do trees grow? Compare the speed of growth of hard and soft woods. Report your findings in class. Fig. 15. — Transverse section through a four-year-old stem of white pine. a, fork; b, cortex; c, phloem; d, cambium; e, xylem;/, secretion reservoir; g, pith; h, medullary ray. (Pharmaceutical Botany, Youngken.) 52. Demonstration. — The museum committee should prepare an exhibit of specimens of wood which are ring porous, diffuse porous, and of evergreens which have resin ducts instead of pores. If no specimens are in the laboratory, try to secure some. They will show their special features better if they are planed and polished in the department of manual training. II WES 53. Committee Investigation. Learn what trees are favored foi street planting in your city. Why are they favored? Make a list of our native trees which are good for city planting and .1 list which are not. Give reasons. Present the results of your inv< tion to the class. For the above information you should visit the city forester or the citv clerk. Fig. 16. — Photomicrograph of a cp tion of a corn stalk t<-> show '.he \ of an endogenous stem, a, Epidermis; f>, cortex an«l pericycle; c, fundamei (pith) tissue with vascular bundles interspersed in it. The large tul bundles are xylem, the small tubes arc phloem. {Plant Ana torn 10. THE STRUCTURE AND WORK OF LEAVES References Civic mid Economic Biology, Aiwood, Studies 1 2 and 1 Experimental Botany, Payne, American Book Co. Plant Anatomy, Stevens, I'. Blakiston's Son & Co. 54. Types of leaves may be studied by having each student bring as many kinds as he ran find to clas When colle< ted, they may be sorted into three groups those of the conifers, palmate, md pinnate leaves. Note the shape of the needles of the pine- and spruo I needles are flattened, spruce needle- are square in section, and pit WPEBTT . ( 24 • PROJECTS AND EXPERIMENTS IN BIOLOGY needles arc long. The foliage of the hemlock, arborvitae, juniper, and cypress should be studied so that it may be recognized at sight if these trees grow in your locality. The pinnate leaves may come from trees, shrubs, and herbs. Sort them into their various types. Do the same with the palmate leaves. 55. Draw some of the leaves which have been brought in and label them with the assistance of the figures in Study 12 of Atwood's Biology. 56. Stomates may be studied by carefully peeling the epidermis from the lower surface of various leaves and mounting in a drop of water under the compound microscope. An onion stem, the leaves of tulips and lilies, and the live- for-ever have an epidermis which is easily removed. Some leaves may be viewed as opaque objects, and if the light is just right, the stomates may be seen. Are there as many on the upper as on the lower sides of the leaves? Can you think of a reason for this variation? Compare leaves which stand erect with those which are held in a hori- zontal position on their stems. Draw some stomates as you see them under the microscope. See Atwood's Biology, Fig. 78. 57. Topics. — How do stomates open and close? Why do they do this? What gases and vapors f the Hve-for-ever pass in and out through stomates? Of what value to the plant is this interchange? 58. Notebook Work on Photosynthesis.— Con- sult the following biologies and write a description of photosynthesis: Atwood, Fig. 80; Hunter, p. 106; Moon, Fig. 26. Answer the following ques- tions. What organs of the plants perform this work? What energy is used? What materials? What are the waste products? What are the products of this action and what is done with them? Why is starch called a carbohydrate? Design a diagram to illustrate your topic. 59. Transpiration. — Split a cork lengthwise in two parts, and hollow out a groove in each half to fit the stem of a plant. Pull the with a portion of the epidermis peeled to show the method of remov- ing the epidermis to view the sto- mates under the microscope. {Fun- damentals of Bot- any, Gager.) LEAVES plant out of the soil with its roots in good condition. Wash them. Fit the halves of the cork around the plant stem near the n nd put the roots in a test tube of water which will hold them. I il tin- cork in the mouth of the tube. Now insert a fine glass tube in the side of the cork so that air may pass into the test tube, and thi seal the cork and plant in with chewing gum, paraffin, or vaselii Weigh the plant and tube carefully and phut- in the sunlight. Fig. 18. — A, Upper epidermis without stomates; B, I rmi» stomates of the fern Drynoria meyeniana. {Heredity and Evolution i Gager.) Weigh again from day to day. The only way in which the I tube can lose water is through the plant, as that which comes out through the glass tube is negligible. Make more than one of th< experiments and compare. 60. Projects.- Consult references and set up some of the many experiments which have been designed to illustrate transpiration. Which demonstration is the best? 61. Diffusion of gases may be illustrated by the instructor shown in the figure. 26 PROJECTS AND EXPERIMENTS IN BIOLOGY 62. Guttation drops may be obtained by using the split cork and test tube described in the experiment above. Place a large leaf in the tube, rolled up if necessary, and seal it in. The leaf should be of a plant which gives off much water. The geranium is not good for this demonstration. See Fig. 81 in Atwood's Biology. Try some other methods also. When does water come out of the water pores in leaves? Do all plants have them? Are guttation drops the same as dew? 63. Project. — Arrange for a committee to plant some seeds in the dark. Care for them well, and they will grow. Do they develop any chlorophyll? How long NH4CI Fk;. 19. — An experiment to show dif- fusion of gases. How does air enter and leave a leaf? (General Science, Brownell.) do they live without light? Report from time to time to the class. 64. Experiment. — Place some green leaves in boiling water for a minute or two. Then place them in alcohol. After a time they will be seen to have lost their chlorophyll. Remove them and note the color of the alcohol. Chloro- phyll is a green pigment composed of a protein containing iron in the "ferrous" condition. If the alcohol is allowed to evaporate the chlorophyll will remain. Is it still green? 65. Projects. — Make skeleton leaves. See Payne's Botany, p. 146. Make blue prints of leaves.—- See Payne's Botany, p. 146. 66. Demonstration. — Set up the apparatus shown in the illustra- tion and collect oxygen in the test tube which is placed over the funnel. Common ditch moss (Elodea) or some other plant which lives in water will do. This experiment does not work as easily as some manuals would lead the experimenter to believe. It must be in bright sunlight, and when the carbon dioxide in the water is all gone it must be given time to collect from the air, or it may be made from limestone and acid and bubbled in. How is this experiment related to photosynthesis? See Payne's Botany, p. 162. I.I. Wl - 67. Microscope Work. Chloroplasts may be seen in green cells with the compound microscope. Secure some spirogyra Se< I 184 in Atwood's Biology) or sonic ditch moss I and pla< under the microscope in a little water. I )<> riot gel any water on the stand of the microscope or on the lense-. Note that the < hlorophyl] is confined to definite bodies within the plant cell. They are bands in spirogyra, and rounded bodies in Elodea. If these plants are not avail- able, various other green plants will do. Draw what you see and label as completely as you can. 68. Teacher's Demonstrations. To Show that Plants Need Oxygen. Follow directions as given at the bottom of p. 96 in Atwood's Biology. To Show that Plants Need Carbon Dioxide. — Repeat as above but put in a dish of pure sodium hydroxide or lime water. The dishes used in these demonstrations should be wide across and shallow. Some plants will live a long time under the above conditions. 69. Demonstration.- Sap circulates through the veins of plant leaves. Prove this by placing various leaves and seedlings with leaves in red ink photosynth. PaUa so that it will be absorbed by the lea! stem or the roots of seedlings and sent out into tin- leavi N that the veins become red. A concentrated soluti< ink will be too strong. It should be diluted. It may take one or tw< complete this demonstration. 70. Experiment to Demonstrate the Presence of Starch in a Green Leaf.- Pluck a leaf from a geranium <>t' the kind which has white markings on it s leaves, and which ha- stood in bright sunlight for about two hour-. Place it in boiling water at om I- 1. • M' 28 PROJECTS AND EXPERIMENTS IN BIOLOGY Tnal il with alcohol as directed above in studying chlorophyll. This is to get the color out. When the leaf is no longer green, place it in a solution of iodine for an hour or more, if necessary. The blue color denotes starch and its absence in the places which had no chlorophyll indicates that it is produced in the green tissue only. ii. FOOD AND ITS USES References Civic and Economic Biology, Atwood, Studies 14, 15, and 16. .1 Civic Biology, Hunter, Chaps. XIX and XX. We have seen how plants secure their food by photosynthesis, and we will consider in the work which follows some of the food problems of animals. We should keep in mind the fact that plants make their food from water, carbon dioxide, and mineral salts; and that animals use the food which plants have elaborated not being able to make it themselves. 71. Problem.— How do molds get their food? Place some moist bread in a covered dish so that it will not dry out and keep it in the dark. Does mold need sunlight? Has it chlorophyll? Does it use the same foods as green plants? 72. Dissolve some glucose or corn sirup in water and add some yeast. Put it away in a warm place in the dark. Does the yeast grow? Compare it with a mold in its food-getting. 73. Notebook Work. — Write an article on the food-getting of green plants as compared with yeasts, molds, and bacteria. The archives committee will select a few of the best to be read to the class. 74. Euglena. — It may be possible to get some euglena from a pond. If not, they may be had from Powers & Powers, Station A, Lincoln, Nebraska, or from some other dealer. Observe them under the microscope. How do they move? Can they swim? If so, how? Note that they are green. This is due to chlorophyll. They live like a plant, and have the advantage of being able to go from place to place. FOOD AND ITS l> Draw several euglena in different positions. Can you show the nucleus, eye spot, and gullet? It will probabl) nol be possible to see the lash. The author has kept a culture of a green protozoan, the euglena, in an aquarium in the Laboratory for Try to make a culture of euglena. Place it in the chargi a committee. 75. Notebook Work. — Animals are divided into herbivorous or carnivorous groups according to whether they eat vegetable or animal food respectively. Some, as man eat both. They are called omnivorous. Make a table of the vertebrate animal- assign! them to one or the other of the three clas Bears and d« are carnivores in spite of the fact that they eat large quantitii vegetable food. Discuss all doubtful cases before placing them in the table. 76. Project. — Make several balanced aquaria and place each in charge of a student. Observe them from time to time a- the- phi: and animals grow. Do they all stay balanced? See At wood's Biology, Figs. 86, 87, and 356. See also Hunter, p. [66; Hodge and Dawson, p. 13, 299, 315. 77. Notebook Work. — Consult some of the following referent and make diagrams of the chemical cycles listed below: Atwood, Figs. 9, 82, and 86; Gruenberg, Chap. XIV j Moon, Chap. 1.III; and Hunter, Chap. XIV. Diagram the carbon cycle first, then the nitrogen cycle, and then the food cycle. Use a ruler and i.»m- pass in drawing your lines so they will be uniform and neat. If time permits, it will be well to write note- explaining each diagram. 78. Food Plants. — See p. 102, Atwood 's Biology, and make table of the common plants which are used a- food. In cadi we use the roots, stems, leaves, flowers, fruits, or seeds. \ each plant to its proper place in the table. It may be well 'k this table out on the board as a class proje< 1, after which it ma\ copied in the notebooks. 79. Caloric values of foods have been overstressed of late If it is desired to do such work, a reference may be consulted. At wood's Biology, p. 107. 3° PROJECTS AXD EXPERIMENTS IN BIOLOGY A//T/?OGf/V Or A//r> t I I I i/vftTiT r/y^r/OAf U i (YOOIU.£, S^ETO TO ANtMALS G/?£EN- -rA&W P / 1 L . /*7Aqt/fr£- Ml/Ait/S 4/ Fig. 21. — The nitrogen cycle as shown in the life of an alfalfa plant. {General Science, Brownell.) Fool) AND ITS I'M 80. Topic— Insectivorous plants capture insects and digest them. Pitcher-plants, sundew, and the Venus fly-trap are described and illustrated in Interesting Neighbors, Jenkins. P, Blakiston's Son 8 I Fig. 22. — The Venus fly-trap, the leaves of whirl) captu {Heredity and Evolution in Plant C tr.) Compare the food-getting ol these plants with other plants and animals. In what situations do they livi I their habitat lacking in essential plant foods? 3 2 PKOJECTS AND EXPERIMENTS IN BIOLOGY 12. CHEMICAL FOOD TESTS Reference Civic and Economic Biology, At wood, Studies 14, 15, and 16. The following tests may be made by each member of the class if laboratory facilities permit; or they may be performed as a demon- stratioD from the lecture table. Each should be written up carefully in the notebook. See Atwood, Study 15; Hunter, the last half of Chap. II; and Payne's Botany, pp. 19-29. 81. Carbon Test. — Place bits of cloth, wood, feathers, etc., in small test tubes containing small amounts of concentrated sulphuric acid. The acid decomposes organic compounds and extracts water leaving the carbon to color the contents of the tube black. It may be necessary to let some tubes stand for quite a while. 82. Starch Tests. — Starch is not soluble as it exists in plants, therefore it will be necessary to boil some starch in a test tube of PlG. 23. — Starch cells of a potato before and after being cooked. Describe what has happened. {General Science, Brownell.) water. Cool it. Add a few drops of a solution of iodine. The starch is changed to starch iodide which is blue. Heat it, the solu- tion should be clear. If it is cooled again, the blue color returns. Iodine may be dissolved in water if a few crystals of potassium iodide are dissolved first. This is better than an alcoholic solution. Test various foods for starch. Is there any starch in sugar? In corn sirup? In honey? In mucilage? Scrape a raw potato and place some of the pulp under a compound microscope. The starch grains have an appearance somewhat like Rye. Buckwheat r . T >> _ s -_L-_ Bean. Ah k< »\\ : Barley. Oat. T J g Maize. Rut:. - ' &i I ^> '■ Pica. Win \ 1 . Fig. 24. — Various types of starch grain een under th Analysis, I.c/J'tnann and Beam.) 34 PROJECTS AND EXPERIMENTS IN BIOLOGY an oyster shell. Grains of starch from different plants have a different appearance. Examine several kinds in water. Can you tell from what plant a sample of starch came by examining the grains? Can you tell if potato starch has been mixed with corn starch? 83. Glucose Test. — When a solution containing glucose is heated with Fehling's solution the copper in the test fluid is oxidized by the glucose, and yellow to deep orange copper oxide appears in the test tube as a precipitate. Fehling's solution may be made as follows: Dissolve 34.65 grams of copper sulphate in 500 cc. of water and put in a bottle. In another bottle containing 500 cc. of water dissolve 125 grams of sodium hydroxide and 173 grams of Rochelle salt (sodium-potassium tartrate). Keep the solutions separate until shortly before they are to be used when they are mixed in equal parts to form Fehling's solution. Heat a dilute mixture of glucose and Fehling's solution in a test tube. Note the beautiful deep orange to red color. Try this with various foods, especially cane sugar, starch, mucilage, and flour. Place some ground cracker, flour, or starch in water and add some diastase or saliva. After a few minutes test with Fehling's solu- tion. What is the action of these two ferments on starch? 84. Protein Tests. — Prepare some white of egg in water. 1. The heat test is made by placing some of the solution in a test tube and boiling. A cloudy appearance indicates the presence of a protein which coagulates when heated. 2. The xanthoproteic, or yellow test, is made by placing nitric acid on some egg white in the test tube and heating gently. It should turn yellow. Now pour out the excess liquid and add enough ammonium hydroxide to neutralize the acid. A deep orange color should appear. 3. The burning test is made by burning a piece of meat or a feather and noting the odor. 4. The sugar test is made by adding a drop of concentrated cane sugar solution to the protein solution in a test tube and then adding a drop or two of pure concentrated sulphuric acid, when a deep red color appears. CHEMICAL FOOD TKSTS (Millon's test and the biuret test give a red and a violet color respectively. They may be found described in Hawk's Physiolog ical Chemistry, and Payne's Botany. They are both very deli< tests.) Apply some of the tests described above to various kinds of foa 85. Fat and Oil Test.- Foods which contain much oil will mal grease spot on paper. It may be necessary to grind the material very fine and press it against the paper. A gentle heat may be of some aid. Be sure that the spot is not a water spo 1 by giving it time to dry or by warming it. If it is an oil spot it will May. Soudan III may be had from the dealers. It is a dye. Place it on the grease spot and then wash the spot with alcohol. N tin- color. 86. Water or Moisture Test— Place some of the material to In- tested in a test tube and hold in a horizontal position over a flame so as to heat the material in the bottom of tin- tube- without heating the top of the tube. If moisture is present, it will collect >>n tin- sides of the tube. If the material is strongly heated the moisture may result from the chemical decomposition of tin- substance which is tested. 87. Test for Mineral Matter. — This is sometimes called tin- ash test. Heat the material to be tested in a crucible until it i- red. Keep it so for a long time. If anything remains it is mineral matter which will not burn or pass off as a vapor. Free salts in a soluble condition may be- detected by soaking tin- material to be tested for a time in water and then altering the water and allowing it to evaporate, when they will be- Kit a- crystals. 88. Review. — How can you detect starch in pulverized sug Starch in glucose? Salt in meat? Starch in ice cream? Glu in candy? Starch in candy? Wool from cotton? Salt in butter? Limewater in milk to keep it sweet? Barley flour in wheat flour? Starch from flour? Glue from mucilage? [f a disput d><»ut any of these questions it should be tried out. that i- th< 1. 89. Milk Tests. Sour milk may be- tested for by placing a strip of blue litmus in it. If tin- litmus turn- red, tin- milk i- Another test is to put some soda in the milk. If it efferv* the milk is sour. Explain tin- chemical action. 1- sour milk us< PROJECTS AMI EXPERIMENTS IN BIOLOGY cooking? Explain. Smell and taste are also good methods of testing sour milk. 90. Butter-fat tests of milk are made by centrifuging the fat from the rest of the milk or dissolving out the fat in ether. The Babcock milk test is most frequently used, but the ether test is more accurate. Get State and Government bulletins from the agricultural departments which give directions for making the test. Also see Bowden's General Science, p. 574. The test may be made before the class as a demonstration. If we should give complete directions for making the test here, it would require too much space, as there are many difficulties to avoid. 91. The formaldehyde test is made by placing some milk in each of two beakers. To one add a small amount of formaldehyde and leave the other as it is. Place a drop or two of a solution of ferric chloride in some pure hydrochloric acid. Add twice as much of this acid to each of the beakers of milk as there is milk. Mix the milk and acid well by rotating the beakers. Place them both in boiling water for some minutes. The milk which contains formalde- hyde becomes lavender to purple in color. Why is formaldehyde added to milk? To determine this take two samples of fresh milk and add a few drops of formaldehyde to one and none to the other. Set them away and observe which becomes sour first. Formaldehyde is a dangerous poison, and must not be used in preserving milk. 13. DIGESTION References Civic and Economic Biology, Atwood, Study 16. Elementary Biology, Gruenberg, Chap. XIX. 92. Committee Project, — Dissect one or more frogs to show the digestive system. Spread the specimens under water in pans and show to the class. The organs may be drawn and labeled. Ward's, Rochester, N. Y. have a model of a frog which may be set up before the class and its organs drawn. Other preparations may be had of the specimens in glass jars with the organs dissected. The DIG] STION nasal cavity PALATE MOUTH CAVITY A* NASAL Pit'. OHAL PHAR\ I LARWvJEAL PHARYNX BILE AND PANCREATIC DUCTS RIGHT COLIC FLEXURE DUODENUM LEFT fOUC V*^9^T. . . v\\ FLEXURE XI VERMIFORM PROCESS Fig. 25. — Diagram of the alimentary canal Morri ,SS PROJECTS AND EXPERIMENTS IN BIOLOGY museum committee may make some preparations of various animals and preserve them in glass jars in formalin. 93. Notebook Work. — Make a drawing of the digestive organs of some animal, or of man; label the parts, and name the digestive juices which each organ supplies. 94. Consult Fig. 91 in Atwood's Biology; pp. 275 and 343 in Hunter's Biology; Figs. 28 and 32 in Gruenberg's Biology; Fig. 114 in Moon's Biology; or Figs. 178 and 165 in Smallwood's Biology and write a description of the similarities and differences in the digestive systems of the frog and man. 95. If it is desired to make a study of the teeth, consult Eddy's Experimental Physiology and Anatomy, p. 60. 96. Salivary digestion was illustrated in connection with the study of Fehling's solution as a test for glucose, which see if it is desired to make a further study of its action. Does it act in an acid medium? In an alkaline medium? 97. Exercise. — Commit to memory the table of digestive juices given on p. 112 of Atwood's Biology and write it as a test. 98. Notebook Work. — Write a description of the passage of digested food from the intestine to the blood system. How does it get through the walls of the intestine? Which foods go through the liver ? Which through the lymphatic system ? See Atwood's Biology, Fig. 93; Moon, Fig. 121; Hunter, p. 354; and Gruenberg, p. 87. 99. Digestion Experiment. — Pepsin may be had from drug stores or from dealers in biological supplies. Prepare some boiled egg. Mince the white very fine. Place some pepsin solution in four test tubes. To the first add nothing, to the second add a drop of dilute hydrochloric acid, to the third add several drops of dilute hydro- chloric acid, and to the fourth add two drops of an alkali (NaOH). Place some minced egg in each test tube and stand away in a warm place for one or two days. In which of the tubes has digestion taken place? Why did it not take place in all of the tubes? In which did it go on the most rapidly? This experiment may be performed by each of four or five students and the entire class may view the results if time and space are limited. Write it up completely in the notebooks and state which tube was the most representative of the actual conditions which exist in the stomach. RESPIRATION AND < lk< I LATION ioo. Pancreatin may be used in a similar manner to illu intestinal digestion. The only place when- faU in the intestine. If you wish to digest fats, use corn oil, oil, or olive oil. The pancreatin musl be fresh and of the besl quali or results will be disappointing. Ii may be made alkaline byaddi a little sodium carbonate. 101. An emulsion may be made to show to the i lass by mixinj light vegetable oil with a dilute alkali and shaking D be fat remain emulsified? For how long? Soap will form from tl emulsion if it is left to stand or is warmed. An understands the chemistry of soap-making is helpful in understanding the digestion of fats. 102. Absorption. — Our problem here is, why are foods digested? Use two diffusion shells such as are sold by the dealers in biological supplies. Suspend each in a vessel of water. PL >me starch which has been mixed with cold water in one and some glucose <»r honey which has been diluted slightly in the other. After some time test the water in the first vessel for starch. Test the water in the second vessel for glucose. Did the starch osmos< Did the glucose? Which digestive juices change starch into glu< Why is this necessary? 14. RESPIRATION AND CIRCULATION Reference Civic and Economic Biology, Atwood, Study 17. 103. Teacher's Demonstration. Secure some defibrinat un- clotted) blood from a butcher, or by killing a chicken, and put it ii bottle. Pass carbon dioxide through tin- blood rapidly from generator. Note that the blood becomes a deep purple in 1 Look at the veins in the wrist and compare. N >w pas oxygen through the blood. It become? a bright scarlet. I (plain h- carbon dioxide and oxygen are carried by the haemoglobin in t ; blood. Why is the blood which flows from a cul always r< Pass carbon monoxide gas through the blood and n becomes a carmine red m c< ' '• In dilute solutions it 4° PROJECTS AND EXPERIMENTS IN BIOLOGY /In bluish-red. Carbon monoxide has such a strong affinity for haemo- globin that it can not be replaced by oxygen as can the dioxide. Does this explain why it is a deadly poison? Can the presence of carbon monoxide be detected by its odor? Why is it dangerous to be in a closed room with a gasoline engine running? In the above demonstration, the carbon dioxide may be obtained by placing hydrochloric acid on lumps of limestone. The oxygen may be obtained from the air and may be pumped through with a bicycle pump. The carbon monoxide may be had by passing gas from the gas jet through the blood, or it may be made by placing concentrated sulphuric acid on crystals of oxalic acid in a generating flask. The technical words used in this study should be carefully spelled on the board, and the experiment written up in the notebook. 104. The function of the diaphragm in respiration may be shown as in the figure. A piece of dentist's rubber sheeting may be tied over the bottom of the vessel. Place a button in its center and fasten a string around the button and the rubber. A toy balloon may be placed on the inside of the glass vessel. Write an explanation of this demonstration. 105. Notebook Work. — From a model of the heart, from charts, from illustra- tions in texts (Atwood, Fig. 99), or from a pig's heart describe the circulation of the blood through the heart. The circulation of the blood of the earthworm may be described from Fig. 95, Atwood'' s Biology. A dissection to show these vessels may be made by some student as a project, but it is usually only a partial success as a class dissection. Put the dissected specimen in the museum case. 106. The operation of the tracheal system of an insect may be described from Figs. 33 and 96, Atwood' s Biology. 107. Red blood corpuscles may be studied under the microscope as directed in Eddy's Experimental Physiology and Anatomy, p. 72. Fig. 26. — Apparatus for an experiment to show the effect on the lungs of depressing the diaphragm. (Elements of Animal Biology, Holmes.) TROPISMS AND !■: I SPl ►] 41 108. The circulation of the blood in the frog's foot strated as directed in Eddy, ]>. 70. 109. The Air in the Lungs. Blow the breatl of cold glass or metal. \\ hal 1 olle< 1 - on the surfai e of the . metal? Blow gently on the hull) of a thermometer. Whal hapr* Blow slowly through a glass tube int.. a glass of fresh lin tcr. What causes the cloudy appearance of the limewati Wriu statement in your notebook telling what you have learned from th< tests. When a fire hums what are the produi I < >mpare with the statement which you have just written. no. Project. — Two hoys may weigh themselvi irately before athletic practice and again after. What became of the materials which were lost? How is the energy of exei irnisl in. Lung capacity may be determined by filling a la vessel, as a bottle, with water either before or after inverting it in another and larger vessel of water. Insert a large glass or rubl tube under the vessel. After taking a normal breath the air from the lungs should be blown into the inverted glass vessel. \ venient scale of measurement should be applied to the side ol tl vessel. Now fill the lungs full to capacity and repeat. Compare with others. Sterilize the end of the tube which you put in your mouth. In the average student's lungs there will remain about ic cubic inches of air after all has been expelled which can be «lri\ < out. What is your average lung capacity? What is your maximum capacity? 15. TROPISMS AND RESPONSES References Civic and Economic Biology, Atwood, Unit III. Experimental Botany, Payne, American Book l The Animal .\fin^_-.'-i vV'7 l r-1 :)■ T HEAT Fig. 28. — Diagram of a tank to show how animals seek optimum conditi which to live. and record the temperatures on the board. This demonstration should be started about two hours before it is to be shown to the class. There will be considerable difference in the results obtained with different kinds of animal-. The more a< tive they are th< ner they will respond. 117. Trial and error reactions may be observed 1>> watching paramecia under a microscope. Place some -» urn in the water win they are and note how they colled around it. Plao ry -mall crystal of salt in the drop where they are and note how the) acl in reference to it. The entire class may work at this if there are enouj microscopes. 118. Draw a diagram of a nerve cell and label all of tin pa How does the impulse enter the cell? What is its COUJ \\ does it pass out of the cell? 44 PROJECTS AND EXPERIMENTS IN BIOLOGY 119. Topic— What is the nature of the nervous impulse? Is it electrical? 1- it chemical? Does it take time to travel, or is it instantaneous? 120. Draw various types of antennae of crustaceans and insects from specimens. A hand lens may be necessary to see the joints of insects' antennae. See Figs. 115, 116, 117, 118, and 120, Atwood's Biology. 121. Draw a diagram of the human ear from some book or model. Label all of the parts carefully and be able to reproduce it, when asked, from memory. 122. Demonstration. — Consult a physics text and set up a pen- dulum to demonstrate the laws of amplitude, of length, of material of the bob. This may be written up in the notebook after it is given to the class. 123. Consult the physics text again and set up a sonometer to illustrate the four laws of strings. They are the law of length, of tension, of diameter, and of material of which the string is composed. Write this up also and state how sound is produced. If these experi- ments have been performed in the classes in general science, a review only should be given now. 124. Student's Demonstration. — Stand before the class and hold a reading glass before a cardboard screen so that it will form an image of the window, or some object out of doors. Consult a good physics text. What is an image? What ways are there of forming them? What is a virtual image? A real image? Which kind is formed on the retina of the eye? If the room can be partly darkened, an image of a burning candle may be made to fall on the screen. 125. Draw a diagram of the human eye in the notebook and label all of the parts. Be able to reproduce the drawing and the names of the parts, when called on to do so, from memory. 126. Draw a diagram of the brain of the frog from Ward's models of the brains of typical vertebrates (Ward's, Rochester, N. Y.). Label the parts carefully, and learn the names of the parts of the brain, and the cranial nerves. See Fig. 136 and the table on p. 160 of Atwood's Biology. See also Fig. 43 in this book. 127. Social Recitation. — It is usually valuable to devote one laboratory period to an interchange of ideas and experiences on PROTOZO \\S animal intelligence, as it has been observed by the members of I class. There may be evidences of superstition, im vation, faulty memory, etc. on the part of some studei 128. Debate. Resolved that the dog can and dees reason. I this debate your most conflicting arguments will (inter ai 1 the proposition, "What is reason?" 16. STUDIES OF PROTOZOANS References General Zoology ', Pearse, Henry 1 1« >I t and Co. General Zoology, Linville and Kelly, Ginn & Co. Practical Zoology, Hegncr, Macmillan Co. Life of Inland Waters, Ncedham and Lloyd, Comstock Pub. < The Protozoa of Iowa, Edmondson, Davenport Acad, of & i. Civic and Economic Biology, Atwood, Study 25. 129. The Ameba. — These animals may be raised in the laboratory. The committee in charge of cultures may L r <» to a pond Bn ik the ice if it is winter.) and secure some water weeds, particularly th< which are covered with a great deal of slime. Place them in some glass pans and let stand for some days, when amebas may be found on the sides of the glass and in the sediment at the bottom. !' will do no harm if the culture gets scum on it- surfai Mak< ral cultures, each different in some details from the other The ame on the sides of the glass should be taken off by rubbing the I along the glass and transferring the material which it coll< microscope slide. If any are found, they should be studied as they may be gone in a day or two. Note how they mo and avoid objects in their path. Can the nucleus be found? vacuole be found? How are the pseudopodia put out and . in? Draw an ameba in several shape- as it ■. Jong. If amebas can not be obtained by the method described had alive from the various dealers, and should l»< They may be had permanently mounted <>n mi< 130. Paramecia. These animals will be found, ith many other protozoans, in the cultures described aboi tam- ing amebas. The hay infusion culture is the si 4O PROJECTS AND EXPERIMENTS IN BIOLOGY should be made, and a little water from a pond or from the ameba cultures should be added to inoculate it. The hay should be chopped fine, and placed in water about two weeks before the protozoans are to be studied. A scum of bacteria will rise to the surface. This is the food on which the paramecia lives. Place some of the scum on a slide and note their movements. We have referred to the avoiding reaction before. Can their cilia be seen? Note whether they go backwards as much as forwards. How rigid is the shape of their bodies? Can the nucleus be found? The oral groove? A vacuole? Watch one gather food. If they go too fast to be seen well, they may be entangled in some fibers of cotton if it is placed on the slide, or as the water dries they will become less active. A thin solution of gelatin will be of value also. Run it under the cover glass. As the protozoans swim into it, their motion is impeded. 131. Other protozoans will be found in the cultures with the amebas and the paramecia. Observe them, try to learn their names, and make some sketches of some of them. You will find various worms and crustaceans also. For the identification of the forms which you find see The Protozoa 0} Iowa, Edmondson, Daven- port Academy of Sciences; and Life of Inland Waters, Needham and Lloyd, Comstock Pub. Co. The identification and enumeration of those found will make an interesting project for an individual or group. 132. Questions. — What is a balanced aquarium? Is a hay infusion balanced in this sense? Why does the culture die out? How long are the protozoans abundant in the culture? Would they become numerous again if more hay were added? How does a hay infusion differ from a balanced aquarium? 133. Division. — When the culture is at its best, you should be able to find specimens which are dividing. Look for them. They will seem to be double individuals. Are they just as active as the ones which are not dividing? Only a few people have seen the ameba divide, but hundreds of paramecia may be seen dividing in a good culture. They are about one half as large as others and are attached end to end. How long does it require to complete the process of division? See Figs. 144, 145, Atwood's Biology. ALCE, MASSES, AND ll RNS 134. Conjugation. — In tin- same culture where the growing rapidly you should be able to find a few individuals which are conjugating. These specimens are attached by their sides ;m«i can be distinguished easily from those which arc- dividin] 135. Draw diagrams of specimens which are dividing and als which are conjugating. A good description of the conjugation paramecia may be found in Hegner's College Zoology. 136. Notebook Work.-- Write a description of the most successful methods of making a culture for paramecia. How many days after preparing the culture did the paramecia appear? How long do they stay? How many days is the culture covered with scum? On what do the paramecia feed? Describe the process of locomotion. Describe any other interesting things which were seen in theculturt Consult references and describe division and conjugation. 137. Plasmodium malaria is the cause of chills and fevers. Atwood's Biology, p. 176 and various other texts and write a descrip- tion of its life history. Accompany your description with diagrams. 17. LESSONS WITH ALGJE, MOSSES, AND FERNS References Practical Botany, Bergen and Caldwell, Ginu & Co. Fundamentals of Botany, Gager, 1'. Blakis ton's Son I'ltf ■ 52 PROJECTS AND EXPERIMENTS IN BIOLOGY 20. CELL DIVISION References Civic and Economic Biology, At wood, Study 32. Text-book of Zoology, Galloway, P. Blakiston's Son & Co. Plant Anatomy, Stevens, P. Blakiston's Son & Co. Being Will Born, Guyer, Bobbs-Merrill Co. 161. Cell Growth. — By using the microscope, examine cells of yeast, pleurococcus, spirogyra or some other single celled plant. Are the cells of the same size? Do you think that the larger cells were once smaller than they are now? Do cells grow? - ! ' I • V B - i5\ m =j) D r '"'■■""' ■■' ) ■ ■ - - : . — ^ G H I Fig. 30. — Diagram to show cell division (mitosis) in plant cells. {Fundamentals of Botany, Gager.) 162. Cell Division. — Examine the same cells as above and note those which have divided. Why has the spirogyra cell division resulted in the production of a filament and the division in pleuro- coccus a group of cells. Are all divisions in the same direction? I I ."\\ i RING PLAN I - 163. Cell Budding.- Examine yeasl cells and note how tl multiply by budding. 164. Draw types of the specimens which have been studied. 165. Chromosome changes in cell division may be shown by using permanent mounts of the root tips of the onion <>r some lily. These slides may be had from the dealers. Find cells which illus- trate all of the stages of division shown in the illustration. The illustration in Atwood's Biology is of a typical animal cell. I shown here is of a typical plant cell. Plant cells have no centro- somes. Write a description of cell division describing all of tin- changes which take place in the chromosome. 21. THE LIFE HISTORY OF FLOWERING PLANTS References General Botany, Densmore, Ginn & Co. Civic and Economic Biology, At wood, Studies 32 and $$. 170. This study must be made from microscope slides or from lantern slides, unless the class and instructor are content to make it from illustrations in books. It is a difficult study for high school students, but it is valuable as completing the outline of the evolution of plants. It is interesting to know how the flowering plant came to be what it is. This study is also of value in understanding tin- subjects of heredity and plant breeding. If it wen- spring, it would be valuable to make a field trip and observe the great variety of flowering plants, and it should be understood that it includes and trees which do not have conspicuous flowers. Understand also that the sporophyte and the grains of pollen an- the only pha the life history of flowering plants which ran be observed naturally. All else must be especially prepared. Read Gager a:: gen and Davis for advanced references. Directions for the study of the microscope slides which may be at hand will have to be written up by the instrw tor a- ii varies in different schools. Some students may assist by copying the directions on the board. See Laboratory and Field I Densmore. 54 PROJECTS AND EXPERIMENTS IN BIOLOGY Fig. 31. — Types of pollen grains as seen under the microscope. A, Typha lati folia; B, corn; C, Ambrosia elalior; D, Philadelphia lily; E, pine; F, buttercup; G, blue beech; H, Althaea rosea, rose-mallow; i\ primrose. {Pharmaceutical Botany, Youngken.) FRUITS WD SI ID DISTRIB1 I I' '\ >. >. 171. Pollen gains may be viewed under the microscope 'II arc of a great variety of forms. See the illustration. If they w not germinated in sugar solution in a previous Study, this in- done now. The pollen tube is a male gametophyte. Sketch some pollen grains and later, some which have germinated. 22. FRUITS AND SEED DISTRIBUTION References Botany for Colleges, Ganong, Macmillan & Co. Practical Botany, Bergen and Caldwell, Ginn & Co. Civic and Economic Biology, At wood. Studies ,^4 and 35. Interesting Neighbors, Jenkins, P. Blakiston's Son & Co. Fortunately, most all fruits may be preserved easily in the museum either in the dried form or in formalin. The museum committee will get ready as many fruits and seeds as is 1 onvenient for the study. Write out the table, which appears in four columns on p. 233 of Atwood's Biology, in one column. \<»w write opposite its proper classification the name of each fruit which you have to study. 172. Draw various ones of the fruits which may be sele< ted. Label their parts carefully and note on the drawing to which cla they belong. Do not include any seeds in the drawings. They are to be studied later. Be able to state clearly the difference 1 tween fruits and seeds. Also, be careful not to ( lassify any fruit- seeds. 173. Make a table of the methods of distribution of fruits in nature. Now go over the fruits which you have Listed in the table classification and list them according to their methods of distribution. 174. Make a table of the method- of distribution of see N and fill it out as you did the one for the distribution <>\ fruits. which are carried by the wind may be released in t ; practical demons! ral ion of how they are a tit t ted by a 1 m renl ol air. After the study is made the museum committee will collect the fruits and seeds and save them for the next 1 lass. 56 PROJECTS AND EXPERIMENTS IN BIOLOGY 1 / / I \ / \ 0) v_r-- "T'P § ^> Q_ ^ ^-O o S o 5 o C O^- 1 o 312 s o o 8 o 8 o 3 In S] I I) DIS1 kll;r I [( each. How many kinds of apples do you I. now by sight? M list of those which you know. I ).» the same for other fruits, I >o you Fig. 35. — Wink't^l st ids which are distributed by the wind. F above — linden, ailanthus, :m• Plant grains of corn at various depths against the sides of a gla vessel, and when the ones which have germinated in the best order and way are ready show the vessel with its seedlings to the class. How deep should corn be planted? Should all seeds be planted at this depth? Why the difference? 25. LIFE HISTORIES OF ANIMALS References Civic and Economic Biology, At wood, Studies 39, 40, and 41. All of the zoologies and biologies deal with this subje< t . Secure the embryological models of amphioxus, frog, and chit k from the de il in biological supplies. 191. The Fish. — Developing eggs of various species of fish may be had from the U. S. Bureau of Fisheries or some of the statioi and from dealers in biological supplies. For reference Kell< and Doan's Zoology; and Civic Biology by Hodge and I >n, Chap. XXVII. 192. Draw a series of developing eggs to show the pr< from an egg to a fish. 193. The Frog. If frogs' eggs were collected and preserved in formalin the previous spring, they may be studied under the mien scope. Try to find two, four, and eight cell stages in tl of the egg. Eggs in various stages of development may be had from the dealers in Biological suppli< 194. Draw the stages of cleavage of the frog g whi< h you find. 66 PROJECTS AND EXPERIMENTS IN BIOLOGY 195. The tadpole may be studied from material which was pre- served from last spring's catch, purchased from dealers, or from charts. See Fig. 224 in Atwood's Biology. Before the frog's egg hatches the tadpole can be seen to move within the white of the egg. When it comes out, it has no mouth but clings to objects with its sucker. It is black and is covered with cilia. Find a stage with externa] gills. As these are withdrawn, the internal ones appear. Which legs appear first? How is the tail disposed of? What does the young tadpole eat? When does it first begin to breathe? When are frog's and toad's eggs laid? When do they develop into frogs and leave the water? 196. Draw a series of tadpoles to show the progress from an embryo to the fully formed frog from actual specimens or from models. 197. The Bird. — Excellent wax models of the stages of develop- ment of the chicken's egg may be had from the dealers. Eggs may be incubated in an incubator and the living embryos may be seen. Chicken, pigeon, and turtle embryos which have been mounted permanently on microscope slides may also be purchased. Consult the illustrations in Study 40 of Atwood's Biology. 198. Draw a series of chick embryos to show development from the egg to hatching. Label as completely as possible, but do not expect to know all about bird embryology in this brief study. If you get the general trend, it will be sufficient. 199. The Mammal. — It will be more profitable, in the majority of schools, to spend more time on the development of the chick and to leave out the study of mammalian embryos. Pig embryos are the most frequently studied. They may be had from the dealers, either entire or sectioned and mounted on microscope slides. It may be profitable to study, observe, or draw a series of wax models to show the development of the ear or another series to show the development of the eye. If this is done consult Figs. 122, 123, 132, 233, and 234 in Atwood's Biology. I III FROG 67 26. THE FROG References Civic and Economic Biology, Atw 1, Figs. 22, <>i, g a ,,| Study 39. General Zoology, Linville and Kelley, (Jinn & Co. New Essentials of Biology, Hunter, pp. 272-2- . Biology for Beginners, Moon, Chap. XXYIII. Comparative Vertebrate Dissection, At wood, P. Blakiston's Son Anatomy of the Frog, Ecker, Oxford. Laboratory Directions in Zoology, Guyer, U. of Wis. Pr< 200. The living frog should be examined first. I'luy may be kept in the laboratory indefinitely by feeding them twice a wick. The first exercise may be a demonstration of how to feed a frog. I'l. them in a dish with glass sides so the class may see what . on. They should be left here long enough to become quiet, and then if pieces of meat are dangled before their noses on a wire, they will take the meat readily. Put the meat on the wire -0 that it may be pulled off easily. Will a frog eat meat that is not moving? Will they take food which is not good for them? ho they -wallow all kinds of food? Are their abilities to taste well developed? Antl • especially attracted by certain colors? What do they do when they secure apiece of food that is a little too large to handle easilj Put one frog in the dark and one in the light. How are their shades of color effected? Note the spots and marking \ they protective? Learn to know the kinds of frogs by their markings. Note that the skin is moist. It is used a- a respiratory organ. Locomotion.— How does the frog walk, jump, and swim? pare the legs. How is each pair used? Compare their joints with those of man's. Locate the elbows, wrist>. knee-, and ankK Note that the frog has no tail. The head of the frog is po 1 of a very large mouth, 1 nostrils, and ears. Find these structures. Can '!><• fr< ik: Can it move its eves? Compare tin- upper and lower lid- The nictitating membrane is a third eyelid which is transparent Observe it. 08 PROJECTS AND EXPERIMENTS IN BIOLOGY internal nares teeth Breathing is accomplished by filling the throat with air and then swallowing it into the lungs. Observe a frog as it breathes. How is the air expelled? Can it breathe with its mouth open? An alliga- tor breathes much the same as a frog, but can do so with its mouth open. Can you explain? Hold the frog between the finger and thumb by placing them under its arm-pits. The frog usually croaks. Can it croak with its mouth closed? Of what value is the frog's ability to croak in nature? Can it croak underwater? Circulation of blood may be shown by placing a frog's foot under the microscope. Various ways of doing this have been devised. If you make this exhibit, do not injure the frog. The dead frog may be placed in a pan of water and cut open on the ventral side to remove some of the formalin in which it has been preserved, or if it is fresh we may study the inside of the mouth. Consult the figure and locate the parts which are named. The Eustachian tube may be traced to the ear chamber by inserting a probe. The lungs of a fresh specimen may be inflated by inserting a blow- pipe in the trachea. The skin is loose and may be removed easily. Note the blood vessels which enter the skin near the fore legs. What is their use? The body-cavity may be explored after a cut is made along its mid-line from the throat to the hip girdle. Find the heart. If the specimen is freshly killed it will be beating. The liver is the large dark red organ in the middle of the cavity. On the frog's left and under the liver is the stomach. Trace the intestine from the stomach to the pelvic region. Note its coils. Near its posterior end it is enlarged to form a rectum. At its terminus is a large sac which is the urinary bladder. esophagus Eustachian tube tongue Fig. 39. — The open mouth of the frog to show the structures within. {Drawn for this work by J. Thranow.) Tin: frog 60 The egg masses may have interfered with the observation of the intestine if the specimen was a female. The eL r L. r ~ are held in a la' bra] Fig. 40. — The arU'rirs of the fr- sac of the ovary until spring when they are laid. How large are they? What is their color? Remove the eggs and find the la r internal jugular ^ femoral sciatic F j 1 . -The veins of the coiled, white tubes which are the oviducts. Their wall- contain stored nutriment which is added to th( a- tiny are laid. I ach 7° PROJECTS AND EXPERIMENTS IN BIOLOGY egg is passed from the ovary into the cavity of the body, from where ii enters the open end of the oviduct to be passed to the cloaca. This is the place where the intestine and the oviducts meet. The kidneys may be seen by pushing the oviducts to one side. They are red -brown bodies. Each is drained by a duct to the cloaca. On the ventral surface of each kidney is a yellow colored, irregular fat body and an orange colored strip of tissue called the adrenal body. Find these bodies. What is known about their functions? The lungs are simple sacs with pitted walls in the chest cavity. They are nearer the back than the liver which covers them. iliohypogastric nerve — — crural nerve -— — 6Ciatic nervr 5t7 \ — — olfactory capsule . palatine ,5 - Jip^'jsN ^"~ """ - ophthalmic \ !k ev^'.'.'^v — eye 2jw5 ni'ti'.-;* %\ U\- maxillary WW 1 ^v _^~0^^ * maxillo-mandibular \V — tympanic membrane \ry — Gasserian ganglion JL-V — hyomandibular k^ — ^jy 7 •" ^ 1 — + -glossopharyngeal v< — ^\A \ 11 v jugal ganglion - — — sympathetic "V - vagus ganglion 43- —The nerves brain and cranial of the frog. Fig. 42. — The spinal nerves and Fig. sympathetic nervous system of the frog showing the brachial and pelvic plexuses. The blood vessels may be found and named by use of the figures. Remember that the blood of the frog passes through the heart twice in making a complete circuit of the body. (See Figs. 98 and 99 in Atwood's Biology.) If the specimens are injected, or are fresh, this will not be difficult. But it is not possible in high school classes if the specimens have been preserved without injection. THE PROG 71 Mesenteries arc thin sheets of tissue which hold the organs of the body-cavity in place Find them and name them after the organ which is suspended in each case. The spinal nerves and the sympathetic nervous system arc shown in the figure. Look in the cavity of the body, along the inner wall of the back, and find the white cords which are the nerves. Com- pare them with the figure. Can you find them all? Those which are associated at the level of the arm form the brachial plexus, and those which unite to send branches into the leg form the the sacral plexus. Each nerve trunk Leaves the spinal cord by two branches which unite to form a spinal nerve. See At wood's Biology, Fig. 138. The brain and cranial nerves are shown in the figure-. With a sharp pointed scissors the skull of the frog may be cut open from above by inserting a point in the back of the skull where the spinal cord leaves and cutting bit by bit until the roof of the skull i> occipital r- prooiic *¥—*■ baaiocclpit*!' — ■quaxMfcl Fig. 44. — Side view of the skull of the bullfrog. removed. The brain should be seen and its parts identified by refer- ring to Fig. 136 in Atwood's Biology. It may not be possible for students of high school grade to identify all of the cranial ner\ which are shown in the figure, but they should be found where they arise near the brain and traced outward as far as possible. The muscle system may be studied by referring to the figures in Comparative Vertebrate Dissection, Atwood, P. Blakis ton's Son & Co.; General Zoology Laboratory Directions, Sigerfoos, Minneapolis, Minn.; Anatomy of the Frog, Ecker, Oxford. The skeleton is divided into the axial and the appendicular parts. The axial consists of the skull and vertebral column. A view of the skull is shown here. If skeletons are available, the bones of the skull mav be identified. The bones of the vertebral 7 2 PROJECTS AND EXPERIMENTS IN BIOLOGY column are the vertebrae. Each consists of a centrum which is the main part of the bone and a neural arch which surrounds the nerve i ..id. At the sides are the transverse processes which terminate in short ribs. It may almost be said that frogs have no ribs. The last bone in the vertebral column is the urostyle. Account for its peculiar shape. The appendicular skeleton consists of the limbs and their support- ing bones. The shoulder girdle is a curved plate of bones and cartilage which supports the front legs. It is not closely attached to the axial skeleton. The humerus is the first bone of the front leg. The radius and ulna are united to form the bone of the fore- arm. How many wrist, hand, and finger bones are there? The pelvic girdle supports the hind legs. Is it attached to the vertebral column? The first bone in the leg is the femur. The tibia and fibula are united in the shank of the leg. The ankle is long and contains two long tarsal bones. How many toes are there? Draw such features of the anatomy of the frog as the instructor may direct. All students may not be asked to make the same drawings. 27. STUDIES ON THE ECONOMIC IMPORTANCE OF DOMES- TICATED ANIMALS AND PLANTS For a reference see Unit V, Atwood's Biology. The author has not been accustomed to do any laboratory work with this section of the work. It has been interesting to work up topics and reports, and devote a few minutes each day to the giving of them to the class; but their nature must depend upon the refer- ences which are available, their number, and upon the time which is given to this unit of the book. 201. Library Committee Work. — Prepare lists of reports on the subject matter of the first half of Unit V of Atwood's Biology which, in your judgment, can be made up from the reference material avai- lable in your library. Submit them to the instructor for approval and let the members of the class select such as they wish to work on. This should be done before this study is taken up in class. VARIATION AND HEREDITY 73 202. Exhibits.- Hie museum committee should prepare exhibits of such grains, fruits, vegetables, etc. as are available and as will be instructive to the class. 203. Government bulletins of the department of agriculture may be had for the asking. Write to the Editor in Chief of the Depart- ment of Publications, Department of Agriculture, Washington, D. C, and get your name on the monthly mailing list of announce- ments of new bulletins. Much valuable information bearing on these studies may be had from these bulletins. They should be placed in charge of the library committee. It is possible to get a catalogue of bulletins which have been published in the past and are still in print. 204. Class Projects. — Make a tabulation of the domesticated plants and list their wild ancestor, or ancestors, and the country from which they came. Repeat the above for the domestic animals. If time is short, a select list may be sufficient in both cases. 28. VARIATION AND HEREDITY AND THEIR APPLICATION TO PLANT AND ANIMAL BREEDING References Civic and Economic Biology, Atwood, Studies 46 and 47. Heredity and Evolution in Plants, Gager, Chaps. IV and V. Being Well Born, Guyer, Bobbs-Merrill Co. Genetics, Walter, Macmillan Co. Elementary Biology, Gruenberg, Part V. 205. Variation Study. — Refer to Fig. 256, Atwood's Biology and make a list of all of the ways in which the two ears of corn differ, the one from the other. When the lists are complete they should be compared in class. Note length, diameter, kernels in the row, size of kernels, rows of kernels, butts, tips, shape of ear, curved or straight, and any other variations which you may note. What might haw- been the cause of some of these variations? 206. Reports may be prepared on cases of discontinuous variations which are known in the literature of science. 74 PROJECTS AND EXPERIMENTS IN BIOLOGY 207. Tabulate all of the animals which you know to produce albino offspring on occasions. List the dates and places of occurrence. Make another tabic for the occurrence of black animals. 208. Exhibits. — Try to secure for exhibition purposes in the laboratory specimens of Andalusian fowls, white rats and mice, guinea pigs, and hybrid plants. 209. Chromosome Chart. — See p. 314 in Atwood's Biology and by referring to the chromosome inheritance chart write an explana- tion of how the laws of Mendel and the theory that the chromosome is the carrier of the determiners of heredity are in agreement. PARENTS SECOND GENERATION Fig. 45. — Chart to show how the chromosome theory of inheritance is in accord with Mendel's laws. The chromosomes which carry the determiners of black color are black in the figure, and those which carry white are white. 210. Exhibit. — If possible specimens of various breeds of corn, wheat, apples, squashes, etc. should be shown to the class. 211. Quetelet's Law. — This is the law of chance. It may be illustrated by taking ten pennies and throwing them up a thousand times and recording the number of heads and tails in a table with eleven columns; or five pennies may be chosen and recorded in a PLANT AND ANIMAL BREEDING 75 table with six columns. In this case it may be sufficient to throw them up about 500 times. Take your results to an adding machine and compare. Plot a curve of the results. Continuous variations follow this curve in their occurrence. This law may also be shown with the apparatus which is illustrated in Fig. 394, Fund a men tals 0} Botany, Gager. Secure ioo earthworms and count the rings in their bodies. Colic. I the data in a chart and plot the curve. Is it a Quetelet curve? Secure ioo ears of corn of the same variety and count the rows of kernels, or measure the lengths, or diameters. Suggest other problems or projects which might be worked out. Do you fully realize the universality of this law? 212. Board Work. — Write down the various types of discontinuous variations in a table form. Recall or give examples of the various cases of mutations of which you know or have read. Assign each to its proper place in the table. When this is done, the table may be copied in the notebook. 213. Trap Nests. — A report may be given to the class on the subject of increasing the production of eggs by trap-nesting the laying hens. 214. The Babcock Milk Test. — A demonstration of this test may be given here if it was not done in connection with the food tests. Of what value is milk testing in improving cows? 215. Corn testing and judging demonstrations may be carried out before the class. See Government Bulletins for directions. 216. A report may be given to the class on the life and work of Luther Burbank. 217. Prepare a list of the wild animals in your community which are hunted and trapped for their furs. Which ones will live and breed in captivity? What are the game laws which protect them? If our wild life continues to decrease as it now is, we will soon pro- duce nearly all of our furs from domesticated, furred animals. If there is a fox, skunk, or muskrat farm in the vicinity it may be possi- ble to make a study of it. 218. Animal Improvement Study. — Refer to Figs. 250 and 251 in Atwood's Biology and make a list of the changes which have taken place in the production of the zebu cattle from the wild banteng. 7 6 PROJECTS AND EXPERIMENTS IN BIOLOGY 29. EUGENICS AND EUTHENICS References Civic and Economic Biology, At wood, Studies 46, 47, 51, and 52. Civic Biology, Hunter, Chaps. XVII and XXIV. Civic Biology, Hodge and Dawson, Chap. XXX. Genetics, Walter, Macmillan Co. Being Well Born, Guyer, Bobbs-Merrill Co. Tin Next Generation, Jewett, Ginn & Co. 219. Reports on state laws on eugenics, marriage laws, population of the asylums of the state, tree ordinances, nature of adenoids, duties of the health department, results of school inspection for teeth, eyes, and other ailments needing attention, suggestions for improvement of the ventilation, lighting, and heating systems of schools, relative humidity, child labor laws in your state, value of pure water and milk, etc., are of great value. We can not hope to make much more progress in civic betterment along biological A oim A b\m □ MALE O FEMALE .... A - ALCOHOLIC !• FEEBLEMINDED Fig. 46. — Three marriages to show how feeblemindedness is inherited. De- scribe in writing what the results are as shown in the diagram. {General Science, Brownell.) lines until the general public has more information of these matters than it now has, and until it has a greater desire to profit by such knowledge. 220. Table of Inherited Defects. — Make a tabulation on the board of the defects which people have which are inherited. If there is doubt about it, write a question mark to so indicate. Copy the table in the notebook and file a copy with the archives committee. EUGENICS AND EUTHENICS 77 221. Research. — Consult the table on p. 306, Atwood's Biology and understand how inherited defects are charted. If you know of any people or animals having inherited defects, try to get some data concerning them and their relatives. When it is collected it should be charted as in the figure. In making such surveys be very careful to avoid giving offense to people who may be sensitive. 222. Family Survey. — Make an inheritance chart of the occur- rence of Mendelian characters in your family. Make the chart as inclusive of as many individuals as possible. Eye-color, hair-color, curly or straight hair, fatness, and musical ability are such character- as may be easily charted. 223. Questions. — Is feeble-mindedness dominant or recessive? Can normal children be born from feeble-minded parents? If feeble-mindedness is due to disease or injury, will it be inherited ? Is insanity inherited? May it be caused by injury? If there are no millions of people in the United States and 20 per cent of them have some inherited defect, how many such people have we? Make a list of human defects and classify them as to whether they are bad enough to be eliminated by segregating those who have, them or should no restrictions be placed upon them. Baldheadedness and fatness are of the kind which should not be restricted. Should one consider the relatives of the person whom one wishes to marry? Is a person to be blamed for being a defective? Therefore, should we not be charitable to them? 224. Shrub Study. — Make a trip through the city to study the shrubs which are used for improving the appearance of yards and boulevards. Make a list of them, and star the best ones. See the catalogues of nurserymen as references. 225. Landscape Garden Plans. — Have the local landscape gardner give the class a talk on the science and art of his profession. Make a diagram of your home and the shrubs and trees which surround it. Is there room for improvement ? Will there be some flower beds next summer? Have some of the plans put on the board and dis- cussed as to possible improvement by the class. 226. Notebook Work. — Answer (he questions which are asked in the studies on eugenics and euthenics in At wood's Biology, Studies 51 and 52. Read the following references and write an outline or 78 PROJECTS AND EXPERIMENTS IN BIOLOGY summary of each: The Kallikak Family by Goddard, the Zeros by Poellman, Noteworthy Families by Galton, The Heredity of Richard Roc by Jordan, and the Descendants of Jonathan Edwards by Winship. 30. THE DOCTRINE OF EVOLUTION References Civic and Economic Biology, Atwood, Unit VI. Heredity and Evolution in Plants, Gager, P. Blakiston's Son & Co. The Theory of Evolution, Scott, Macmillan & Co. 227. Field Trips. — Go to a stone quarry, gravel bed, the shore of the ocean, or one of the Great Lakes and study the fossils which are to be found there. Go to a museum and observe the fossils which are there. Various members of the class may be able to bring fossils to the class for observation. 228. Reports may be given on the ancestry of the horse, elephant, camel, birds, mammals, ancient and primitive man, plants of the carboniferous period. 229. Demonstration. — Compare the skeletons of various animals to demonstrate that all vertebrates are built on the same plan. What other systems may be used to show this? 230. Table of Vestiges. — Make a tabulation of the various vesti- gial structures of animals which you know and list their probable use in ancestors which had them in a perfect form. 231. Reports on the lives of some of the great men of biology may be prepared and given from time to time as they are ready. 232. Overproduction Computations. — If we start with a pair of flies in the spring, and the female lays 200 eggs, and the young develop and lay eggs again in 30 days, and the summer lasts five months, how many flies will there be at the end of summer? If a certain weed produces 3,000 seeds in a season, and all grow each year, how many weeds will there be in ten years? If each weed weighs ten pounds, how much will all of them weigh? If a pair of eagles produce two young each year and live to be 100 years old, and if breeding takes place the second year, how BACTERIA, YEASTS, AND MOLDS 79 many eagles will there be at the end of ioo years? If this problem is too long, it may be estimated. 233. Struggle for Existence Experiment.— Plant several kinds of seeds in a box or tray. Plant a great many seeds. Give the culture the best of care. What seedlings survive? Did they struggle? Is it not obvious that they can not all live? 234. Reports.— List the different kinds of the following animals and plants which man has produced by natural selection. Do not be discouraged if you can not give a complete list. Get as many pictures to show as you can. Varieties of dogs. Varieties of chickens. Varieties of doves. Varieties of apples. Reports of famous biological experiments and discoveries will be interesting and valuable. 31. BACTERIA, YEASTS, AND MOLDS References Civic and Economic Biology, Atwood, Studies 56 and 57. Practical Botany, Bergen and Caldwell, Chap. XI. 235. Bread mold may be grown on bread by moistening it and placing it in a warm, damp place for a day or two when it will be covered with the hyphae of the fungus; and in a day or two more, the black spore cases will appear. Growth tests for bread mold may be made as follows: Secure eight wide mouthed bottles or tumblers. Place a piece of bread which is wet in each vessel and treat each as follows: 1. Do nothing. This is the control. 2. Remove the bread from the glass. Clean the glass and dry it. Dry the bread completely and replace it in the glass. 3. Cover the piece of bread with dry salt. 4. Cover the bread with vinegar or some other acid as boracic. 5. Place enough sugar on the bread to cover it. Corn sirup may be substituted for the sugar. 8o PROJECTS AND EXPERIMENTS IN BIOLOGY 6. Place the glass containing the moistened bread in boiling water in a double cooker or a sterilizer. Keep covered after removing. 7. Place this one in a refrigerator. 8. Place on the bread a dilute solution of formalin. Place all but No. 7 in a warm place and keep each vessel covered to prevent evaporation and more infection. In order to make sure that each was infected with mold, it might be well to inoculate each piece at the start. The cultures should be examined at the end of four days and the results written in the notebook. Be sure to explain why mold failed to develop in the sterile cultures. 236. Microscopic Work. — Bacteria may be spread on microscope slides, dried, stained, and viewed with the high power. Yeasts are easily seen. They are very large cells. Place a drop of the culture in which they are growing on a microscope slide and view under the low and high power. What is the shape of the cells? Note how they grow by budding. Can you find a nucleus? A drop of iodine on the slide will enable you to avoid starch grains. How? Draw some yeast cells to show their shape, nuclei, and their method of growth and reproduction. 237. Project. — Refer to Atwood's Biology, Fig. 299 and make some wax models of various kinds of bacteria as suggested. 238. Molds. — From some of the cultures of bread mold which you have grown, you may secure material which can be viewed under the microscope. Find the hyphae, stolons, rhizoids, sporangio- phores, and spore cases (sporangia). Make a drawing showing these structures and label carefully. 239. Culture Medium.. — The best medium for the cultivation of bacteria is the beef extract-agar-bouillon. To make it, dissolve ten grams of each of the following materials in 200 cc. of water: Leibig's beef extract, salt (NaCl), and peptone. In 800 cc. of boiling water dissolve ten grams of agar-agar (or 100 grams of gelatin). The agar must be given considerable time in which to dissolve, and must be kept at a boiling temperature in a double cooker. Pour the first solution into the second and filter while hot through cotton. It should be clear. If it is not, it should be heated again and refiltered, BACTERIA, YKASTS, AND SCOLDS 81 Pour the hot culture medium into sterilized test tubes and Petri dishes. The dishes should be covered immediately and the test tubes should be plugged with sterilized cotton. Set these away to be inoculated in the following experiments. Note. — This solution should be made by the instructor or by a responsible committee. If the medium is to be used for bacteria, it should be made slightly alkaline by the addition of sodium carbonate; but if it is to be used for molds, it should be slightly acid. Determine the acidity or alkalinity after it is filtered by using litmus paper. Fig. 47. — Bread mold (Rhizopus nigricans) to show its habit of growth. A, Older plant with ripe spores; B, younger plant with unripe spores; myc, mycelium; sph, sporangiophore; sp, sporangium; si, stolon. {Fundamentals of Botany, Gagcr.) 240. Where may bacteria te found? — Expose the Petri dishes in some of the following ways. To the dust of the room while it is being swept. To dirt from under the finger nails. To a comb after passing it through the hair. Wash the hands in a small amount of water and place a drop of it on the culture. Scrape the teeth with a dry, sterile tooth brush and inoculate a culture with the scrapings. Get some dust from the road, from a window ledge, from a basement, and other places and inoculate cultures. Keep the cultures in a warm place and do not let them dry out. Watch them and report the growths as they take place. Do not remove the covers when examining Petri dishes. Compare the S2 PROJECTS AND EXPERIMENTS IN BIOLOGY growths in the different dishes. How can you tell molds from bacteria? Are there any differences in the kinds of molds and the kinds of bacteria? Do you fully understand how these fungi got into the Petri dishes? Are bacteria everywhere in the house and out of doors? Probably none of the bacteria which you have grown Fig. 48. — A plate culture of colonies of bacteria grown from a bit of dust from a cow stable. (Microbiology, Marshall.) are dangerous to man as producers of contagious diseases, but if you had secured your inoculating material from a sewer, spittoon, or scab it would be dangerous. 241. Pure cultures of bacteria may be made by thrusting a sterilized needle or platinum wire in a spot of bacteria in a Petri dish and then thrusting it in the culture medium which you have saved in a test tube. Be very careful to avoid letting any foreign bacteria BACTERIA, YEASTS, AND MOLDS 83 get into the tube when the inoculation is made. After a few days the tubes may be examined. If you were careful, there will be but one kind of bacteria in a test tube. Do you fully appreciate how careful one must be to avoid bacteria which cause decay or disea 242. Problem. — If the bacillus tuberculosis divides every half hour when it is growing rapidly, and you should become infected with it, how many germs would there be in your body at the end of ten hours? Twenty hours? One month! What prevents them from multiplying as fast as they might? 243. Project. — Secure several kinds of food and vegetables. Cut the vegetables in slices and mix the foods with water. Keep them warm and moist. The class should see them each day. Which foods are attacked the more readily? Are any resistant to decay? 244. Committee Field Trip. — Some members of the class may go into the woods and find shelf fungi growing on trees. Note whether the trees are alive or dead. On what kinds of trees are they found? Bring some of the speci- mens to the class and put them in the museum. Give a report of your trip to the class and file a record of it with the archives committee. 245. Museum Exhibit. — The museum committee will prepare an exhibit of the various kinds of fungi which may be in +U~ ™ tl u- u i_ e 1 FlG - 4 9- — FcrnuMUati.-n the cases. I hose which are harmful tube for the study of gas for- to our fruit trees are of great economic mation by yeasts and bacteria. _^ ... . ' , . , (From Pit field ajter Williams.) importance. Edible mushrooms which have been preserved in formalin may be seen now and a field trip planned for the spring, but more of them arc to be found in the fall. If there is a mushroom cellar in the city it may be possible to visit it. 246. Yeast plants may be grown in dilute solutions of sugar, glucose, honey, sirup, or dough. Some of the material may be put 84 PROJECTS AND EXPERIMENTS IN BIOLOGY in fermentation tubes, and some of them placed in a refrigerator and some in a warm place. Which shows the most gas at the top of the tube? Smell of the cultures. What is the gas which is produced? Some of it may be passed from a flask through a tube into some fresh limewater. How does this prove the gas to be carbon dioxide? 247. Reports. — How is grain alcohol made on a commercial basis? How is cider made? How is vinegar made? Read the reports to the class. 248. Questions. — Why does salt pork keep? Why does smoked meat keep? How does sugar preserve? How does vinegar pre- serve? Why do tomatoes keep better when canned than corn or pumpkin? Can you make pumpkin keep when canned in the kitchen? Will teeth which are kept perfectly clean decay? Which is better, a broom or a vacuum cleaner? 32. BACTERIA AND CONTAGIOUS DISEASES OF MAN References Civic and Economic Biology, Atvvood, Studies 58 and 59. Civic Biology. Hodge and Dawson, Chaps. XXI-XXIII. Civic Biology. Hunter, Chap. XI. New Essentials of Biology, Hunter, Chap. XXX. Practical Botany, Bergen and Caldwell, Ginn & Co. Do not experiment with bacteria which cause disease in man. It is dangerous. They may be studied from models, charts, and pictures. 249. Statistical Projects. — Consult bulletins of the departments of health — national, state, and city — and make charts showing the decrease in deaths from typhoid, yellow fever, tuberculosis, and smallpox in recent years. To what has this been due? 250. Make charts to show the increase in certain seasons of the year of pneumonia, malaria, typhoid fever, and summer complaint. What causes this seasonal fluctuation? 251. Collect statistics to show the value of vaccination for small- pox, and the use of antidiptheric serum. Do these figures prove that these practises are valuable? CiiXTAC.IOUS DISKASI'.S OF MAX 85 Collect statistics to show the decrease in deaths of infants in recent years? Docs the milk inspection and quarantine enforcement help in this matter? Collect figures which show that cancer is increasing. How do you account for this? 252. Topics may he prepared giving the symptoms, incubation periods, and methods of treatment for some of our common conta- gious diseases. 253. References for the above may be difficult to find. The journal of the American Medical Asso- ciation is valuable, as are other reliable magazines. You should not trust all books and periodicals for your infor- mation. There is much incorrect in- formation in the current literature on the subject of disease and health. 254. Life History of the Mosquito. — If it is now spring, the eggs and larvae of mosquitoes may be found in stagnant water. Let each member of the class search for them. Report all of the places where they are found. Place the wrigglers in screened aquaria in the laboratory and watch them develop. Specimens may be taken out and drawn in outline. Make a series to show how they look at different ages. Adult mosquitoes may be dried and placed on microscope slides, then covered with a drop of balsam, and a cover glass mav ■ FlG " 5 °~ . °. J pi pirns, t. Tracheal gills; r, be pressed down upon it. This prepa- respiratory tube. (Entomolo ration is not perfect but it will be of / '" /v '""- ) value in studying the parts of the mosquito under the microscope. Find the antennae of the males and females and compare. Note the long legs. Can mosquitoes stand on the surface of quiet water? Do you know any other creatures which can? How many wings has a mosquito? Why do they buzz? Onlv the females do this. 86 PROJECTS AND EXPERIMENTS IN BIOLOGY Find the probosis and distinguish its parts. See Studies 25 and 58 in At wood's Biology. Place some mosquito larvae in an aquarium with goldfish and minnows. (?) Make a list of the ways of fighting mosquitoes. Fig. 51. -Comparison of the pupae of Culex (at left) and Anopheles (at right)- enlarged. (From Howard.) Which methods can be used in your community? If you live in a district where there is no malaria, is it worth while to fight the mosquito? 255. Personal Survey. — See General Science, Bowden, p. 596 and make the survey which is outlined there. If you have made it last — — „ 7 ^r-, .„.„„-„„_ .- , , , ,, > •»:• ?• • i">»y>,l!»>/»»W>it Fig. 52. — Anopheles mosquito at left, culex at right, to show their characteristic attitudes when at rest. {Elements of Animal Biology, Holmes.) year, repeat it now and note any improvement which may appear. Be especially accurate in the examination of your skin, eyes, ears, nose, and mouth. You will not be required to show your report to the members of your class. CONTAGIOUS DISEASES OF PLANTS 87 33. CONTAGIOUS DISEASES OF PLANTS References Fund a menials of Botany, Gager, Chaps. XIX to XXI. Fungus Diseases of Plants, Duggar, Ginn and Co. M ycology and Plant Pathology, Harshberger, P. Blakiston's Son & Co. Chic and Economic Biology, Atwood, Studies 60 and 61. Principles of Botany, Bergen and Davis, Ginn and Co. Bulletins of the United States Department of Agriculture, and of the Slates. 256. Charts. — See Fig. 305 in Atwood's Biology and make similar charts to show the life histories of other fungi which cause diseases in plants. 257. Exhibits may be made of the specimens which are in the museum. Collect as much material showing plant diseases as you can. Some of it must be kept in formalin, but much of it can be dried. 258. Reports may be prepared and given on the more common plant diseases. Describe how they are caused. What parts of the plant are affected. How they are carried. How they pass the winter. How they are treated and cured or eliminated. 259. Table. — Make a table listing the common plant diseases, the plants which they injure, and the method of preventing or fighting them. Let each student work on a chart, exhibit, report, or table. 260. Lilac mildew has been a favorite for the study of a parasitic fungus for a long time. Gather the leaves of the lilac and dry them. View the spore cases under the microscope and draw them. How do the filaments of the fungus emerge from the leaf? There is a similar fungus on the leaves of willow which is good material for study. Consult a reference and learn the life history. SS PROJECTS AND EXPERIMENTS IN BIOLOGY 34. WEEDS References Practical Botany, Bergen and Caldwell, Ginn & Co., Chap. XXV. Civic and Economic Biology, At wood, Study 62. Civic Biology, Hodge and Dawson, Chap. VII. The departments cf agriculture of Minnesota, Michigan, Ohio, and Wisconsin issue excellent bulletins on weeds. There are several issued by the U. S. I department of Agriculture. 261 . Field Trip. — If it is now spring, go into the fields and find such weeds as you can. Learn their names and get as much of the following information from literature and by observation as possible. How large does the weed get? Where does it grow? What soil is best suited to it? Can it grow in water? Is it easily frozen? Does its root live over winter ? What crops does it damage the most ? Has it any other methods of reproduction than by seed? How are its seeds scattered? Does it produce many seeds? Is it poisonous? Does it have a bad taste or smell? Is it extensively eaten by animals or insects? Is it easily uprooted or trampled out? Can it grow well in the shade? Does it harbor any harmful insects? Does it produce burs, berries, or large seeds? Has it a blossom? What effect might the above have on the ability of the weed to maintain itself? It may be possible to collect the above in the form of a table for the common weeds of your community. 262. Survey. — The survey committee may look for poison ivy, barberry, poison sumach, poison hemlock, poison oak, jimson weed, and fennel. Can some of these weeds and shrubs be removed? Keep a record of where they were found and the next class will follow up the work of their eradication. 263. The following figures in Atwood's Biology are pictures of weeds. Which ones of them have you found? Figs. 10, 26, 28, 29, 40, 41, 43, 47, 63, 64, 106, 107, 108, 156, 163, 174, 176, 178, 180, 181, 182, 191, 192, 194, 195, 199, 202, 311, 312, 313, 314, 316, 317. 264. Weed Seed.— Examine a sample of clover seed which con- tains the seeds of weeds. Use a lens. Compare the weed seeds which you find with those shown in Fig. 317, Atwood's Biology. How many kinds have you found? What per cent of the seed was PARASITIC WORMS 89 weed seed? What is the law in your state in regard to weed seed in seed which is sold for planting? 35. PARASITIC WORMS References General Zoology, Pearse, Henry Holt & Co. Textbook of /.oology, Galloway, P. Blakiston's Son & Co. Civic and Economic Biology, At wood, Study 63. Civic Biology, Hodge and Dawson, Chap. XXIV. 265. The tapeworm may be observed in the laboratory by passing a preserved specimen around the class. Microscope slides on which are mounted proglottides to show their parts may be had from the dealers. These may be observed under the microscope and com- pared with Fig. 319 in Atwood's Biology and drawn. Label all features completely. Ward, Rochester, N. Y. makes an excellent model of a proglottid of the tapeworm. It may be drawn by the students. How do the eggs get out of the ovaries to the exterior? What is the function of the uterus? 266. Ascaris may be observed from bottles containing preserved specimens. Sometimes eggs may be found in the females. They may be seen under the microscope. 267. Trichina may be studied from microscope slides. They may be had from the dealers. If the slides are made from the llesh of the rat or pig which contains the larva?, the student should consult Fig. 321 in Atwood's Biology and make sketches of what he sees under the microscope. 268. The hook-worm may be studied from slides, but few schools are supplied with such material, and it is not easily obtained. 269. Topics. — Secure bulletins from the U. S. Public Health Service and report on such phases of the hook-worm problem as may seem advisable. 270. Diagrams of the life histories of various parasitic worms may be made by students. These mav be put in the notebooks or on the board. Each diagram should be accompanied by a descrip- tion. The texts by Pearse, Gallowav, and Hodge and Dawson are good references. go PROJECTS AND EXPERIMENTS IN BIOLOGY 36. INSECT PESTS References Civic and Economic Biology, Atwood, Studies 64-67. Civic Biology, Hodge and Dawson, Chaps. X-XY. Economic Zoology, Kellogg and Doan. Elementary Biology, Gruenberg, Chaps. LXXV and LXXIV. Biology for Beginners, Moon, Chaps. XXIII-XXV. Economic Entomology, Lochhead, P. Blakiston's Son & Co. Entomology, Folsom, P. Blakiston's Son & Co. Elementary Entomology, Sanderson and Jackson, Ginn & Co. Injurious Insects, O'Kane, Macmillan & Co. 271. Excursion. — If there is a greenhouse near the school, it may be profitable to make a trip to it to study their methods of controlling insect pests. 272. Exhibits. — The museum committee should place on exhibit such injurious insects as are in its possession. Write out a legend for each exhibit stating something of the life history, damage done, and methods of control. 273. Survey. — Let each student be on the watch for insects as they appear this spring. Capture them and bring them to the class. Recognize them as beetles, flies, butterflies, etc. and try to learn their individual names and what they live on. Keep a record of the earliest appearance of insects common to your community and file the record with the archives committee. 274. Topics and Reports. — Let each student prepare a paper on some harmful insect. Make a chart to go with the paper if you can. For an idea as to how to make such a chart, see Figs. 315,324,326, and 335 in Atwood's Biology and similar figures in the other references. 275. Tables. — Prepare a table of the sprays which are used as stomach poisons and state in the table what kinds of insects are fought with each spray. Make a similar table for sprays which are contact poisons. Make another table of stomach poisons which are not applied through a spraying nozzle. 276. Laboratory work should be done on an insect which has chewing or biting mouth parts and on one which has sucking mouth INSECT PESTS 91 parts. See Figs. 32, 328, 329, and 330 in Atwood's Biology and the figures of the grasshopper in Unit 6 of this manual. Insects having chewing mouth parts which are easily studied are caterpillars, grubworms, beetles, dragon flies, and grasshoppers. [nse< 1- having piercing and sucking mouth parts which may be studied arc squash bugs, assassin bugs, electric light bugs, cicadas, and some of the flii After carefully consulting the figures in reference books, each student I li h Fig. 53. Fig. 54. Fig. 53. — Mouth parts of the mosquito to show a type of piercing mouth parts, a, Antenna; e, compound eye; h, hypopharynx; /, labrum-epiphary nx ; li, labium; m, mandible; tnx, maxilla; />, maxillary palpus. [From Folsom, after Dimmock.) Fig. 54. — The head of the housefly. {From limns.) should make a study, with the aid of a lens, of the mouth parts of a chewing and a sucking insect. Make sketches of the mouth parts and label them carefully. Do you understand why stomach poisons do not kill bugs? If bugs do not eat the leaves of a plant, how do they do it damage? Which is the more primitive type of mouth? 92 PROJECTS AND EXPERIMENTS IN BIOLOGY In examining mouth parts of insects, the student should use a fine tweezers and a needle point. Those of the chewing insects may be removed and sketched apart from the head or they may be left on. It will be best to leave the mouth parts of sucking insects on the head and sketch them in that way. They should he separated for observation with great care or they will be broken. The needle point is best for this purpose. Thrust it between them near the head and gently work it down to the point of the beak parting the mouth parts as you do so. 277. Exhibit. — The supplies committee should make an exhibit of the various chemicals which are used in fighting insects. They may be put in glass bottles and set out for observation with such notes as may seem appropriate. Caution. — Some of the chemicals are very poisonous. 278. Review. — If the grasshopper was dissected in a previous study, it should be reviewed now; but if not, it will be well to turn to the directions there and make a careful study of the structure of the grasshopper considered as a typical insect. 279. News Item. — Flies are being bred in our city at the rate of one million every twenty-four hours. The committee on civic surveys of the biology class of the high school reports finding a manure heap on River Avenue which is pro- ducing a million flies every day. We wonder if all of the citizens of Blank have been getting their share of these flies. A statistician on the committee reports that there are 104 flies for each family in the city, and several times that figure for each grocery store per day. We hasten to inform the curious that it will be necessary to start at once if they desire to see this marvel of insect breeding, for the manure is being removed today. We regret to announce the destruction of so beautiful a fly paradise, but the school physician held a conference with its owner with the result that it was sold for fertilizer at a satisfactory profit. The above news item is a gem of biological literature. It con- demns no one, is somewhat humorous, and lets those who have manure piles know indirectly that they must be removed. There should be considerable manure for sale the day following the publica- tion of such an article. Is it necessary to publish such an article in the press of your city? When the fly season opens, there should be no manure piles. Such piles do little harm in the winter, but when spring comes the flies which have wintered over in them in the form of maggots and pupae begin to come out, and other flies lay their eggs there. Appoint a committee to make a survey. INSECT PESTS 93 280. Fly Breeding Project.— Secure some fly eggs or young larvae and some manure. Place them in a glass jar and observe their development from day to day. I Mace them in the care of some student who will see that the culture is kept properly until the flies develop. Keep a record of the length of the stages of development. Does food or temperature affect the length of the stages? 281. Laboratory Study. — With the aid of a lens and the compound microscope the fly should be carefully examined. Dip each fly in a solution of formalin before handling it to kill any germs which may be on it. The wings are gauzy and covered with hairs. Note the veins which keep them stiff. The head is possessed of two large compound eyes. Find the bristle-like antennae. The mouth parts are adapted for lapping up fluids. Can you identify the mandibles, maxillae, and labium? The body is divided into a head, thorax, and abdomen. The thorax is composed of three fused somites. Each somite bears a leg. Note the hairs on the legs. Are they well adapted to carrying bacteria? Place a fly's foot under the compound microscope and view it. Find the two hooks, the pad, and note the hairs. The abdomen is composed of somites which are easily distinguished. How many are there? Note the hairs. Is the fly a good carrier of germs? If time permits, sketches of vari- ous parts of the fly may be made. 283. Fly Trap Exhibit. — A committee may be appointed to secure some fly traps, or they may be made. Exhibit them to the class. See Hodge and Dawson's Biology, Chap. X. 284. Fly poison may be made by placing a little sugar or honey in a saucer of water and adding a small amount of formalin. It may be well to place a slip of paper in the dish for the flies to light on. All water must be removed from the room. Flies require large quantities of water and are fond of water containing a little formalin. If there are flies in the laboratory, this experiment may be tried; but there must be no water for them to get at, other than the poison. 285. Arachnids. -Examine specimens of spiders, centipeds, and millipeds and make out the tables on pp. 424 and 432 of Atwood's Biology. 94 PROJECTS AND EXPERIMENTS IN BIOLOGY 286. Reports may be given on the life histories and methods of control of various arachnid pests. Government bulletins will be found to be the best references. 287. Spider webs may be studied as projects. How are they made? What are they used for? How many kinds are there? A few minutes of the recitation hour may be devoted to an exchange of information and ideas on spider webs. 37. RATS AND MICE References Civic and Economic Biology, Atwood, Study 68. Civic Biology, Hodge and Dawson, Chap. XVII. Bulletins of the U. S. Department of Agriculture. 288. David Lantz estimates that a rat does two dollars worth of damage every year of its life. How much wheat would it eat to amount to this figure? Corn? Flour? Each student will make a list of the ways in which rats have been known personally to destroy property. Bring the lists to class. Compare and average them. It may be well to collect the averages in a table. 289. Bubonic Plague. — Consult references and make a diagram of the life history of bubonic plague. 290. Survey. — A survey committee should collect some infor- mation on the rat problem in your city. Where are they the most abundant? Are there any open sewers? Can a movement be started and carried out to have the sewers covered? Are there any garbage dumps in the city? Is it possible to have the garbage burned? Are any of the merchants or manufacturers suffering loss by rats? In making surveys, you should always be courteous and diplomatic. 291. Problem. — If a rat brings forth ten young to a litter, and breeds four times in a year, how many rats will there be at the end of five years? FISH AND POND LIFE 95 38. FISH AND POND LIFE References Fish Culture in Ponds and other Waters, Meehan, Macmillan & Co. Civic and Economic Biology, Atwood, Study 69. Civic Biology, Hodge and Dawson, Chap. XXVI I. Biology for Beginners, Moon, Chap. XX VII. General Zoology, Pearse, Henry Holt & Co. Life of Inland Waters, Xeedham and Lloyd, Comstock Pub. Co. 292. Excursion. — If there is a pond, lake, or stream in the vicinity, an excursion should be made to it. Dip nets, glass jars, pails, etc. should be taken along. What animals do you find in the water? Is the water clear, running, muddy, or stagnant? What is the condition of the bottom? What is the source of supply of the body of water which you are visiting? What kinds of insects are present? What kinds of molluscs? What kinds of plants? What kinds of crustaceans? List them. Catch as many of the animals which live in the pond as you can. Place them in aquaria in the laboratory and study them. What ones are eaten by fish? Which ones eat others? What is the source of all food in water? Make a list of the fishes which are known to inhabit the body of water. Do you know what each feeds on? W 7 hat might be done to increase the number of fish which could be taken from the pond each year? Discuss the questions raised above when you meet in class the next day. 293. Aquaria. — Review the work done with aquaria last fall. Are any of the aquaria in the same condition in which they were left last fall? What changes have taken place? Review the chemi- cal cycles in ponds and aquaria. Understand the relationships of plants and animals in water. What kinds of fish have you been able to keep in the laboratory? 96 PROJECTS AND EXPERIMENTS IN BIOLOGY 39. THE PERCH (DISSECTION) References Comparative Vertebrate Dissection, At wood, P. Blakiston's Son & Co. Laboratory Directions in Elementary Zoology, Guyer, U. of Wis. Press. General Zoology, Linville and kelley, Ginn & Co. Civic and Economic Biology, At wood, Study 69. 294. Study a Live Fish in Water. — How does it pass water over the gills? How does it swim? Are all of the fins used? Note the tins. The one at the tail is the caudal. Those along the back are t he dorsal fins. Those under the tail are the anal fins. Those which arc paired are the pectoral fins near the head, and the pelvic fins along the sides of the body farther back. Find the nostrils. What are they used for? Find the eyes. Are they movable? Feed the fish. How do they find the food? Study the scales. How are they arranged? Are they all of the same size? Note how they lap over the ones behind them. Find the lateral line which is a line from above the eye along the side of the body to the tail. It is a line of sense organs. Draw the fish which you have observed. Label all of its parts carefully. 295. Dissection of Perch. — Specimens with the ventral wall of the body cut away may be kept in formalin from year to year and used in this study for examination, or fresh specimens may be dissected. Make a cut along the mid-line of the body and carry it forward to the pectoral girdle and back to the anus. Now cut away the sides oi the abdominal walls. This exposes the visceral organs of the perch. Push a probe into the mouth and find where it enters the stomach. Note the shape of this organ. Find the pyloric appen- dages at the place where the stomach and intestine meet. How many are there? What is their function? The liver is the dark red organ forward from the stomach. How many lobes has it? Can you find the green gall bladder? Trace the coiled intestine through the fat which surrounds it to its opening to the outside. How many coils are there? Can you find the pancreas and spleen? What are the functions of these organs? The pancreas is in a very simple form in the perch. THE PERCH 97 The reproductive organs are situated along the intestine and vary greatly in size with the season of the year. Trace their openings to the exterior. The air bladder is the silvery sac in the dorsal part of the body-cavity. What is its shape? How is it attached? The kidneys are situated between the bladder and the backbone. They are of a dark red-brown color. What is their extent? lateralis system' ophthalmic maxillary \ 'mandibular hyomandibular Fig. 55. — The brain and ten cranial nerves of the perch as seen from side view. {Comparative Vertebrate Dissection, Atwood.) The heart is situated between the gills in the thick triangular area. Cut into it and observe the heart. Find the atrium (auricle) and the ventricle. It will be difficult for a student of high school grade to make out the blood vessels without injection, but they are charted in Figs. 98 and 99 in Atwood's Biology. Understand how the blood traverses the body of a fish and compare it with that of man and the frog. The brain and cranial nerves of the perch are shown in the illustra- tion. Cut away the roof of the skull and remove the fatty material 98 PROJECTS VXD EXPERIMENTS IX BIOLOGY which surrounds the brain. The most anterior lobes comprise the cerebrum, the second pair are the optic lobes, and the third unpaired lobe is the cerebellum. Try to find the cranial nerves which are shown in the illustration. You may not be able to find them all. The muscles of the perch are of the segmented type along the sides of the body. They are an evidence of the fact that vertebrated animal- are segmented as is the earthworm, but these evidences are much less evident in the higher forms. Strip a piece of skin from the side of the body and tail and observe the muscles. For refer- ences on the anatomy of the perch consult Comparative Vertebrate Dissection, Atwood, P. Blakiston's Son & Co. and General Zoology, Linville and Kelly, Ginn & Co. Draw such parts of the anatomy of the perch as your instructor may direct. 40. BIRDS References Civic and Economic Biology, Atwood, Study 70. alimentary Biology, Gruenberg, Chap. LXXVII. Civic Biology, Hodge and Dawson, Chaps. IV and V. .Y< w Essentials of Biology, Hunter, pp. 286-302. Biology for Beginners, Moon, Chaps. XXXI and XXXIT. Bird Xeighbors, Blanchan, Doubleday Page & Co. 296. Laboratory Work. — The following study may be made from a live bird or from a mounted specimen. Distinguish the following regions: head, neck, body, and tail. The bill is peculiar to birds. Does it contain any teeth? Find the nostrils. Note their shape and position. Are they covered with feathers? Find the eyes. Are they possessed of lids? What is the color of the eyes? What is the shape of the pupil? Find the ears. Is there an external ear? How is the ear covered? The neck and body are covered with feathers which are so arranged as to shed the rain and to offer as little resistance to flight as possible. How are the wings folded? How many joints are there? The long feathers are firmly set in the flesh of the wing. Note how they overlap when the wing is spread. Examine a large feather. The part which was in the flesh is the quill. The stiff central portion BIRDS 99 is the rachis. The barbs run out from the rachis and possess barbules which lock them together. How many joints are there in the legs? How much of the leg is covered with feathers? Note how the scales are arranged. How many toes are there? On what part of the foot does the bird walk? Are the feet webbed? What are the toe nails fitted for? The tail of a bird is short, but it may contain long feathers. Com- pare them with those of the wings. Is the tail broad or pointed. What are the uses of birds' tails? Draw a bird from side view in outline and label its parts. 297. Migration Chart. — Make a tabulation of the dates of arrival of the migratory birds which pass through your section of the country. Let each student be on the watch for birds and record those which he sees. Post the list in the school and compare lists from year to year. 298. Field Study. — Go into the woods and fields on Saturday in groups of less than ten. If there are too many in a group, the birds will be frightened away. Have notebooks with you and record the names of the birds which you see. These trips should be started before the leaves come out, because the birds are more easily seen then. When the birds begin to build their nests, the process of nest building should be observed. In what situation does each bird build? What materials go into the nest? How are thev fast- ened together? Do both birds assist in building? When are the eggs laid? What is their color? Do both birds incubate them? What are the young like? Do both birds feed them? What do they feed them? A blind may be made and a watcher placed in it to make a daily record of the food given to the nestlings. The watcher should be relieved every hour. Are the birds which you have watched beneficial? Do owls hunt all night? It will not be necessary to watch the song birds after dark. Aside from nest building the songs and colors of birds are the most interesting. Learn to know them by their colors and songs. Note differences in males and females. What differences may be noted in young and old birds? It is difficult to see the color of a bird when it is between you and the sun, or when it is in the bright light. Colors show best in quiet woods. IOO PROJECTS AND EXPERIMENTS IN BIOLOGY Watch a sparrow's nest while the young are being feed. You may be surprised at the large number of insects which are fed to the young. Sparrows do much good and some harm. 299. Bird Calendar. — List all of the birds of the community as summer residents, winter residents, permanent residents, and migrants. Give the dates of arrival and departure. This calendar should be started by the first class and corrected and amplified from year to year. It should be placed in charge of the archives committee. 300. Survey. — A tabulation may be made of the shrubs in the community which bear fruits which are eaten by birds. What can be done to increase the number of such shrubs? Will this have a tendency to increase the number of birds in the community? 301. Bird Boxes. — Arrange with the manual training department to make some bird boxes. Have an exhibit of them. When they are set up, they should be put out of the way of cats. • . - INDEX Absorption, 39 Acid secretion, 14 Adaptation, 4 Aerial roots, 14 Ailanthus, 59 Air, 5 Albinos, 74 Alcohol, 26, 84 Alfalfa, 30 Algae, 47-49 Alkali, 38 Alligator, 68 Ameba, 45 Ammonium nitrate, 2 Andalusian fowls, 74 Animal intelligence, 45 Antidiphtheric serum, 84 Apparatus, 1 Apple 56, 60, 74, 79 Apt era, 10 Aquaria, 29, 46, 86, 95 Arachnids, 93 Arborvitae, 24 Archives, 1 A ristolochia, 20-2 1 Ascaris, 89 Avoiding reaction, 46 Babcock test, 36, 75 Bacteria, 28, 79-86 Balanced aquarium, 46 Banteng, 75 Barberry, 88 Barley, 35 Bean, 63 Bears, 29 Bees, 6 Beet, 14, 16 Beetle, 3, 6 Begonia, 60 Berries, 57 Bird boxes, 100 calendar, 100 Birds, 57, 66, 78, 98-100 Biuret test, 35 Blood, 40 corpuscles, 40 Brace roots, 14 Brain of frog, 44, 70, 71 of perch, 97, 98 Bread mold, 79, 81 Brook, 4 Bryophyllum, 60 Bubonic plague, 94 Buds, 18-23 Bulbs, 19, 60 B urban k, 75 Butter, 35 Butterflies, 6 Calendars, 51 Calories, 29 Camel, 78 Cancer, 85 Candy, 35 Capillarity, 17 Carbohydrate, 2, 24 Carbon cycle, 29 dioxide, 26, 27 28, 29, 39 monoxide, 39 test, 32 Carrot, 14 osmometer, 16 Cats, 100 Cell, 52-53 budding, 5 j division, 52-53 growth, 5a 101 102 INDEX Cellj turgor, 16 Centipeds, 93 Chemical compound, 2 cycles, 29 Cherry, 19, 57 Chicken 3, 66, 79 Chlorophyll, 26, 28, 48 Chloroplasts, 27, 47 Chromosomes, 53, 74 Cider, 84 Circulation, 39-41, 68 Clay, 17 Cleavage, 65 Clematis, 59 Clover, 88 Conjugation, 47 Committee, 1 Compass plant, 4 Cones of pines, 50 Contact poisons, 90 Contagious diseases, 84-87 Copper oxide, 34 sulphate, 2 Corms, 19, 60 Corn, 18, 62, 63, 64, 65, 73, 74, 94 judging, 75 oil, 39 s,talk, 23 testing, 75 Cotton, 18, 35 Cottonseed oil, 39 Cottonwood, 60 Cow, 3 Crawfish, 10-14 Crayfish, 10-14 Crop rotation, 18 Crustaceans, 44 Crystallization, 2 Culture medium, 80 Dahlia, 60 Diastase, 34 Diaphragm, 40 Diffusion, 25, 26 Digestion, 36-39 Digestive juices, 38 system, 36, 37, 38 Diptera, 10 Ditch moss, 26 Dog, 3, 29, 45, 79 Domesticated animals, 72-73 plants, 72-73 Dough, 83 Dove, 79 Drainage, 18 Duck, 3 Eugenics, 76-78 Eagle, 78 Ear, 13, 44 Earthworm, 4, 40, 42 Eggs, 65, 69 Element, 2 Elephant, 3, 78 Elm, 59 Elodea, 26, 27 Embryos, 66 Emulsion, 39 Energy of exercise, 41 English ivy, 21 Environment, 4 Ephemerida, 10 Euglena, 28 Euthenics, 76-78 Evolution, 78-79 Excursions, 4, 5, 18, 49, 77, 78, 83, 88, 9°> 95> 99 Fascicled roots, 14 Fat, 2, 39 tests, 35 Feeble-mindedness, 77 Fehling's solution, 34, 38 Fennel, 88 Fern, 25, 47-49 Fermentation tube, 83 Ferric chloride, 36 Fibrous roots, 14 INDEX I03 Field trips, 4, 5, 18, 49, 77, 78, 83, 88, 90, 95, 99 Fire, 41 Fish, 65, 95 Flies, 3, 6, 78, 91, 92, 93 Fly larvae, 93 poison, 93 traps, 93 Flour, 35 Flower calendar, 51 Flowering plants, 53-55 Flowers 5, 50-51 Food, 5, 28-36, 64 cycle, 29 tests, 32 Forestry, 21 Formaldehyde test, 36 Formalin, 80 Fossils, 78 Fox, 75 Fungi, 83 Furs, 75 Frog, 36, 41, 43, 65, 67-72 Fruits, 55-59 Game laws, 75 Geotropism, 41, 64 Geranium, 26, 60 Gleocapsa, 47 Glucose, 2, 28, 34, 35, 38, 39, 65, 83 tests, 34 Glue, 2, 35 Goldenrod, 5-6 Goldfish, 86 Grafting, 60-61 Grass, 5 Grasshopper, 6-10, 92 Growth 3, 52 Guinea pigs, 74 Guttation, 26 Hay infusion, 45 Heart, 40, 68, 97 Heat test, 34 Heliotropism, 42 Hemipicra, 10 Hemlock, 24 Heredity, 53, 73~75 Honey, 39, 83 Hook-worm, 89 Horse, 78 Human eye, 44 Humus, 17 Hybrids, 74 Hydrochloric acid, 36, 38 Hydrotropism, 42, 64 Hygroscopic water, 17 Hymenoptera, 10 Ice cream, 35 Images, 44 Inflorescence, 51 Inheritance chart, 76, 77 Inherited defects, 76, 77 Insectivorous plants, 31 Insect mouth parts, 90 Insect pests, 90-94 Insects, 6, 40, 44, 90-94 Iodine, 32 Iron, 26 Irritability, 2, 3 Jimson weed, 88 Juniper, 24 Law of chance, 74 Leaves, 5, 23-28, 49, 5°, 60 blue prints of, 26 of conifers, 25 of pines, 50 palmate, 23 pinnate, 23 Lepidoptera, 10 Library, 1 Light, 5 Lilac mildew, 87 Lilies, 24, 53 Limestone, 17, 26 104 INDEX Limewater, 35, 41, 84 Linden, 59 Litmus, 16, 35 Live-for-ever, 24, 60 Lumber, 50 Lungs, 41 Lung capacity, 41 Lymphatic system, 38 Malaria, 84, 86 Mammal, 66, 78 Man, 3, 37 Manure, 30 M;iple, 59 Matter, 2 Meadow, 4 Mendel, 74 Mice, 74, 94 Migration chart, 99 Milk, 35 tests, 35-36 Millipeds, 93 Millon's test, 35 Mimosa, 3, 42 Mineral matter, 35 Minerals, 2 Mitosis, 52 Mosquito, 85, 91 Moisture test, 35 Molds, 28, 60, 79-84 Mosses, 47-49 Mucilage, 35 Mulch, 17 Mushrooms, 83 Muskrat, 75 Nectar, 50 Nerve cell, 43 Nervous impulse, 43, 44 Nitrogen, 18, 29, 30 cycle, 29, 30 Odonata, 10 Oil tests, 35 Onion, 24, 53 Orthoptera, 10 Osmosis, 16, 39 Overproduction, 78 Oxygen, 26, 27, 39 Pancreatin, 39 Paramecia, 43, 45 Parasitic worms, 89 Park, 18 Pea seed, 63 Pendulum, 44 Pepsin, 38 Perch, 96-98 Percolation, 17 Perfume, 50 Personal survey, 86 Petri dishes, 82 Photosynthesis, 24,28 Phototropism, 42, 64 Pigeon, 66 Pine tree, 23, 49-50 Pitcher-plant, 31 Plane sawed oak, 21 Plant diseases, 87 propagation, 60-62 Plasmodium malaria, 47 Plate gardens, 15 Pleurococcus, 47, 48, 52 Pneumonia, 84 Pumpkin, 16, 84 Pure cultures, 82 Poison hemlock, 88 ivy, 88 oak, 88 sumach, 88 Pollen, 51 grains, 54, 55 Pollination, 51 Pond, 4 life, 95 Potassium chlorate, 2 dichromate, 2 iodide, 32 INDEX I05 Potassium sulphate, 2 Potato, 3, 18, 60 Protein, 2 tests, 34 Protozoans, 45-47 Quarter sawed oak, 21 Quetlet's law, 74 Raspberry, 58 Rats, 74, 94 Reason, 45 Respiration, 68, 39-41 Responses, 41-45 Rhizomes, 19, 60 Robin, 3 Rochelle salt, 34 Rocks, 17 Root hairs, 14, 16, 17 Roots, 3, 6, 14, 17, 18, 27, 60, 63 Saliva, 34 Salivary digestion, 38 Salt, 2, 35, 43, 64, 79 Sand, 17 Sanitation, 1 Sap, 20, 27 Seed germination, 62-65 Seedlings, 27, 62-65 Seeds, 60, 62-65 Sensitive plant, 3, 42 Sewers, 94 Sheep, 3 Shelter, 5 Shrubs, 77, 100 Silver nitrate, 2 Sirup, 83 Skeleton leaves, 26 Skeletons, 78 Skunk, 75 Smallpox, 84 Snake, 3 Soaps, 39 Soda, 35 Sodium bromide, 2 chloride, 2 hydroxide, 27, 34 iodide, 2 Soil, 5, 14 Sonometer, 44 Soudan III, 35 Sour milk, 35 Sparrow's nest, 100 Spiders, 93 Spider webs, 94 Spirogyra, 48, 52 Spores, 60 Sprays, 90 Spruce, 23 Squashes, 16, 74 Squash seed, 63 Starch, 2, 27, 32, 35, 39 grains, 32, 33 iodide, 32 tests, 32 Stem, 5, 18-23, 60 Stomach, 38 Stomach poisons, 90 Stomates, 24 Strawberry, 58 Sugar, 2, 16,35,55, 79,83,84 Sundew, 31 Sunlight, 2, 5, 28 Tadpole, 66 Tapeworm, 89 Tap roots, 14 Teeth, 38, 84 Temperature, 5 Thermometer, 41 Thermotropism, 43 Thigmotropism, 42 Tomatoes, S4 Tracheal system, 40 Transpiration, 24, 25 Trap nests, 75 Tree calendar, 51 Trees, 18, 21 PROPERTY i/v 1 06 N. C State C Tree stumps, 22 Trial and error, 43 Trichina, 89 Tropisms, 41-45 Tuberculosis, 84 Tubers, 19, 60 Tulips, 20, 24 Turtle, 3, 66 Typhoid fever, 84 Ulothrix, 48 * Vaccination, 84 Variation, 73-75 Vaucheria, 48 Ventilation, 1 Venus fly-traps, 31 Vestiges, 78 Vinegar, 79, 84 INDEX Walking fern, 60 Water, 5 test, ss Weeds, 4, 14, 78, 88-89 Weed seed, 88 Wheat, 35, 74, 94 White pine, 22 Wild animals, 75 Willow, 21, 60 Wood, 50 Woods, 4, 18 Wool, 35 Worms, 89 Xanthoproteic test, 34 Yeast, 28, 79-84 Yellow fever ; 84 Zebu cattle, 75 871 B5« K/01/00 41245 10 St if s I V