TEXAS AGRICULTURAL EXPERIMENT STATION AGRICULTURAL AND ME CHANICAL COLLEGE OF TEXAS W. B. BIZZELL, President BULLETIN NO. 257 DECEMBER, 1919 DIVISION OF ENTOMOLOGY THE COTTON OR MELON LOUSE_ LIFE HISTORY STUDIES B. YOUNGBLOOD, DIRECTOR common STATION, BRAZOS COUNTY, TEXAS STATION STAFFT _ A DMINISTRATION B Youucspooo, M. S., Director A. B. CONNER, B. S.. Vice Director J. M. Jones, A. M., Assistant Director CHAS. A. Fizuuzn. Chief Clerk A S. WARE, Secretary . . . . . . . . . . . . . . . . . . . . . Executive Assistant Cmnuzs Sosoux, Technical Assistant VETERINARY SCIENCE *M. FRANCIS, D. V. M., Chief H. Scnumr. D. V. S.. Veterinarian D. H. BENNETT, V. M. D., Veterinarian CHEMISTRY G S. FRAPS. Ph. D., Chief; State Chemist S. E. Asnvrw. M. S., Assistant Chemist S. LOMANITZ, B. S.. Assistant Chemist F B. ScmLLn-c. B. S., Assistant Chemist J B Surm. B. S., Assistant Chemist HO RTICULTURE H. NESS, M. S. Chief W. S. Horcmuss. Horticulturist ANIMAL INDUSTRY J. M. Jones, A. M., Chief; Sheep and Goat Investigations IJ. C. BURNS. B. S., Animal Husbandman in Charge of Ree] Cattle Investigations (on leave) M Sn Rwuon. B . Poultryman .l B McNuLTY. B S, Dairyman O. E.'IVICC()\NFLL, B. S.. Animal Husband- man in Charge of Swine Investigations Ba wan, B. S., Assistant Afllmtll Hus- ENTOMOLOGY M - C» TMovAnv. Ph. D., Chief; sum Ento- mologist H. J. Remnmw, B. S., Entomologist H. B. PARKS, B. S., Apiculturist ——-, Assistant Entomologist AGRONOMY A. B. Cowman, B. S., Chief A. H. Lemma, B. S., Agronomist E. W. Graven, B. S., Agronomist H. H. LAUDE, M. S., Agronomist PLANT PATHOLOGY AND PHYSIOLOGY J. J. TAUBENBAUS, Ph. D., Chief FEED CONTROL SERVICE F. D. FULLY n, M. S., Chief J AXES SULLIVAN, Executive Secretary FORESTRY E. O. SIECKE, B. S.. Chief; State Forester Pl ANT BREEDING E. P. PIuMBsn-r, Ph. D., Chief FARM AND RANCH ECONOMICS H M. Euow, M. A., Chief SOIL SURVEY "W. T. CARTER, Jn., B. S., Chief J. F. S-rnouo, Soil Surveyor T. M. BUSHNELL, B. S., Soil Surveyor W B. FRANCIS, B. S., Soil Surveyor ‘bandman SUBSTATIONS ho. l. Beeville, Bee County No. 8. Lubbock, Lubbock County R. E. KARPER, B. S.. Superintendent I. E. Cowurr, M. S., Superintendent No. 2. Troup, Smith County W. S. Horcmuss, Superintendent Angleton, Brazoria County No. 3. REYNOLDS, M. S., Superintendent E. B. No. 4. Beaumont, Jeflerson County A. H. PRINCE. B. S.. Superintendent No. 5. Temple, Bell County D. T. KILLOUGH. B. S., Superintendent No. 6. Denton, Denton County _ C. H. MCDOWELL, B. S., Superintendent No. 7. Spur, Dickens County _ R. E. DICKSON, B. S., Superintendent s As of December 1, 1919. D. I.. JONES. Scientific Assistant G. M. RoyvE, Forest Nurseryman and Ir- rigationist No. 9. Pecos, Reeves County J. W. JACKSON, B. S.. Superintendent No. l0. (Feeding and Breeding fiubstntlon), College Station, Brazos County -—————-———-—, Superintendent E. Gun-IRON, Scientific Assistant No. 11. Nacogdoches, Nacogdoches County G. T. McNEsS. Superintendent **No. 12. Chillicothe, Hardeman County A. B. Cnou, B. S.. Su erinlendenl V. E. Herman. B. S., cientific Assistant No. l4. Sonora, Sutton-Edwards Counties E. M. Pea-ens, B. S., Superintendent In cooperation with School of Agriculture, A. d: M. College of Texas *In cooperation with the School of Veterinary Medicine, A. & M. College of Texas. "In cooperation with the United States Department of Agriculture. CONTENTS. P101: Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 7 Distribution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Scientific Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . I . . . . . . . . 11 Allied Species . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 12 Common Names . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Economic’ Importance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Food Plants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 14 Feeding Habits . . . . . . . . . . . . . . . . . . .y . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Methods of Study . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Life History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 16 Description of Forms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 17 Number of Generations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 Age at Which Females Reproduce . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Reproduction Period . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Total Young Produced . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 Average Number of Young Daily . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 Longevity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3'7 Rate of Increase . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 3'7 Effect of Temperature on Development . . . . . . . . . . . . . . . . . . . . . . . 37 Viviparous Development. . . .p . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3'7 Seasonal History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 3'7 1916 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 Insectary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 Field . . . . . . . . . . . . . . . . . . ." . = . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 Insectary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 40 1917 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 Field . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 Migration Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 41 Cotton . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 Watermelon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 Musknielon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 Cucumber . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 ' Okra . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 Cowpea . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 44 Squash . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 Pumpkin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 Gourd . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 i4 CONTENTS. PAGE Hibernation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 46 Alternate Host Plants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46 Annual Life History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 46 Relation of Ants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 46 Natural Enemies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 48 Parasite . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 48 Predacious Enemies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 48 Lady Beetles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 48 Syrphid Flies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 49 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 49 Literature Cited. . . ._ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 Bibliography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 99°F’? ILLUSTRATIONS. Generation Series Studies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. i PLATES. PAGE‘ Type of Life History Rearing Cage.» . . . . . . . . . . . . . . . . . . . . .. 16- Insectary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 38 Seasonal History Cage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40' Cage SheIterQ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 42' FIGURES. World Distribution of the Louse . . . . . . . . . . . . . . . . . . . . . . . . . .. 8» Chronological Distribution of the Louse in the United States. . 10‘- ‘ 3r [Blank Page in Original Bulletin] BULLETIN N0. 257. DECEMBER, 1919. THE COTTQN OR MELON rouse LIFE HISTORY STUDIES BY *F. B. PADDOCK, M. S. INTITRODUCTION. For over a quarter of a century the people of this State have had to contend with the ravages of the cotton or melon l.ouse. When the insect was first discovered in Texas it was a pest of melons, and it has always caused much damage to this class of crops. Years later a plant louse was found on the cotton in many localities in the State, but it was a few years afterward, before it was known definitely that the plant louse ~of melons was the same species as the one attacking cotton. Even to- day there is much confusion among the growers concerning the identity of these plant lice. The importance of this pest cannot be overdrawn when it is realized ‘that every person who plants cotton may have to reckon with the rav- ages of this pest; that large plantings of melons and allied plants are soften totally destroyed by the pest; and that every home garden is men- aced by it. The injury caused by this insect is not always charged to it but often to the weather. The great loss which has been suffered by the presence of this pest is hard to appreciate and can hardly be esti- mated in terms of dollars. ' Work was started on the study of this insect in March, 1916. The detail work on the life history was completed by May of 1917. Acknowl- edgment is hereby made of the assistance given by O. K. Courtney, for- merly Assistant Entomologist, during the summer of 1916. Since Oc- tober of 1916 much valuable assistance has been rendered by H. J. Rein- hard, Entomologist, in all phases of the work on this insect, and due credit is given at this time. The work has consisted of life history studies to determine the num- =ber of generations that may occur in this locality, in a period of twelve months; of migration tests to secure information on host plants; and of a study of insect relations. Collections have been made at many points within the State as well as some in other States. Seasonal notes have been made wherever possible. HISTORY. In 1854, Glover(1) in making a report of a trip to Columbia, South Carolina, says: “The much-dreaded cotton-louse was not found very *Resigned September 15, 1919. TEXAS AGRICULTURAL EXPERIMENT STATION. “EEQEQMERREQ was,» 4 REE?” Tun COTTON on MELoN Lonsn. 9 abundantly at this late season.” From this remark We are led to believe that this insect had come t0 be a recognized pest of cotton at that date. In another place he says, “Yet I have seen old stands in Georgia with their young shoots completely covered with this pest as late as Novem- ber.” From these records it is impossible to say When this "insect first appeared in the United States and in exactly What locality. The insect first attracted attention as a pest of cot-ton. It Was not until 1882, when Ashmead(6) described his citruill/i, that this insect Was known as a pest of melons in Florida and also in Georgia. This latter locality was one of the first to suffer from the insect as a cotton pest. In 1881 the same insect Was found to be a cotton pest. The following year the same insect proved very destructive to cucum- bers in Illinois, although it was not described until 1883 by Forbes(8) as cu-cumeris. In 1880 this insect was reported from Florida as injurious- to oranges and in the same year it was also reported from New Jersey as a pest of melons. It was also reported from Brazil that year as oc- curring on cotton. The following year it Was recorded in Tennessee on melon vines. In 1.882, Ashmead(7) in redescribing his C’. citrifolii includes material of goss-ypii, from oranges in Florida, as a pest of that plant. This mistake was made WhGII gossypii was considered as a dimor- phic form of citrifolii. In 1883 the insect was reported again on melons from Florida and also on melons and cucumbers from Kansas. The following year it was found on oranges in California. In 1890 it was first reported from Massachusetts and Nebraska; melons and cucumbers being the hosts in each State. It was in this year that the species was reported on oranges in Australia. The insect was first reported from Arizona and Missis— sippi in 1891, on melons and cucumbers in both States. The first report from Texas was in 1892, when the insect was taken on melons at Laredo; the following year it was taken on melons at Rockport. In 1892 the insect was reported on oranges from the West Indies and was taken again in 18941 from oranges. It was in this year that the insect was found on cotton in several localities in Mexico. Following this date the pest has become established in almost every State upon some one or more of its many hosts. In 1907 it was first reported on cotton from the Hawaiian Islands and recently it has been found on melons and cucumbers from Sweden. DISTRIBUTION. The insect was first discovered on cotton‘ in Georgia and South Caro- lina. Later it was reported on melons from Florida. ' Soon afterwards the species was reported on melons from New Jersey and one year later from Tennessee, on the same host. At this early date, and before the pest was established widely in the United States, it was reported on cotton from Brazil. Soon it was reported from Kansas, and a year later its presence in California was recorded. Closely following these records were reports of the presence of this insect in Nebraska and Massachusetts. During the same year the presence of the species was» noted on oranges in Australia. In 1892 the insect was found on oranges v in the West Indies, and was recorded again in 1894 on the same host". It was not until 1907 that the insect was recorded from Hawaii, 1O 1‘EX;XS AGBIGULTURAL EXPERIMENT STATION. dwfivbm wwficb ma» E 320A m5» .3 nofiznmppwwfl fimomwowvcohsO d ogwwm E ma? , \y ~mQ E . on? O mm? . | .9 uma MMQ u $ m ii . . . ..... n- Q3 wMQ ma Q . Tun COTTON OR MELoN LoUsE. 11 " ' i/Ibut at that time it was found on several of the islands and on a variety fof hosts. Fig. 1 shows the present known. World distribution of this species, ;gtogether with the dates of the first recorded occurrence in each locality, §as well as the host upon which it was first found. i, In Fig. 2 isshown the chronological distribution of this insect in fthe United States with hosts of the early records of occurrence. In tTexas, the louse is present wherever cotton, melons, and the other host [plants are grown. ' SCIENTIFIC NALIE. This species was first mentioned by Gloverfl) in 1854 when he says, ;?“The cotton-louse made its appearance again during the cold, damp weather of November.” The location of which he spoke is assumed to ibe Columbia, South Carolina, and at this time he classified the insect ias “Aphis P.” No description was made of the species other than, “the adult insects are said to be about one-tenth of an inch in length, often of a dark green color, sometimes black.” I-le figured both apterous and alate forms in two views. Mention was made of the presence of this insect in Georgia, where it evidently had been a serious pest for years as it was familiar to the cotton growers. The following year Glover(2i) again mentioned the “cotton louse” in his article on Cotton Insects, as ‘fl-Aphis ?,” but no further information was given than was contained in the first article. g Mention of this insect was not made again until 1876 when Glover( 3) makes a note of its presence and refers to the account of the pest made in 1855. At that time the specific name of gos-sypii was first applied to the species although no further description was given than that con- ‘ta-ined in his paper on the insect. In the following year Thomas(4¢) _in his list of aphids found in the United States, records Aphids gossymi without author and refers to the account by Glover(2). Thomas described the species as “green or yellow, thorax striped with black.” Cotton was given as the host. In 1880, Ashmead( 5) described a plant louse from orange as S. citrifolii which has been considered by many writers as a synonym of A. gossyplzli. It is now considered, however, that citr/ifolii is a distinct species. In another paper during the same year, Ashmead(6) described a species of aphid from watermelons in Florida and Georgia as A. citru-lli. This species is now considered a synonym of gossypii. In 1882 Ashmead('7) redescribed citrifolili, and it is now assumed that some of the material probably was gossypii. Another species described at that time as new, is now considered to be Rh opalosiphum, persica-e Sulzer. In 1883 F0rbes(8) described and figured a species of aphid as Aphis ‘cucumeris which infested cucumbers, watermelons, and muskmelons. His description of the forms is as follows: “Winged female: Head black, with red or black eyes, the latter usually with a red tubercle behind. Thorax sometimes jet black through- out, sometimes with the prothorax yellowish. Abdomen yellowish-green with black edges, and with blackish margins to segments. Legs yellow, with coxae and distal parts of tibiae and femora dusky or black. Cor- nicles cylindrical, black; tail yellowish, rostrum yellow, with black tip. The antennae are six jointed (apparently seven), with a setaceous tip 12 . TEXAS AGRICULTURAL ‘EXPERIMENT STATION. tl1ree times as long as the basal part of the joint. The sixth jo' the longest, the third next, the fourth and fifth nearly equal. All- cept the basal joints are marked with inibricated transverse ridges. wings are mo-re than twice as long as the abdomen, hyaline, with sti and veins dusky yellowish. The tail extends beyond the tip of body. Width of thorax .022- inch, of abdomen .08 inch, of head. inch. Length of body .054 inch, of antennae .052 inch, of cornicles. inch.” a “Pupa: Head and prothorax, base and tip of antennae dusky, Q‘ dark red, sides of mesothorax and metathorax white, wing pads bl’ abdomen brownish yellow except posteriorly, where it is green. 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QMDQNQQQEQH. uoucfinoUlwowAom noiaponumv A 03am. 29 THE COTTON on MELQN LOUSE. e2“. d :55 d . u. mm ma H. . H . . . . w w N Q N . . m3 2. Q. .... m . w % O O w .. mw. OO Ox w .. . . . . w. w O w . ww. S. mO m w mO . . . .. w. m N O O . . m.ww. mm OO .N m... 3 E w d. _ a Q . WE E ww . .4 :E< w . . . .mw w ow w O O . . ww ow. NO . .5 . . . Ow N O w . . m.ww. OO w . . mm“ m. w . . TH... W w m. . N...“ w... Wm O . ON m...» ww Nm . . . w. N O O Q Nw. Nm NO wN w w % Om O w O . w.w. NO NO ON i . w w O w . Ow. Nm wO mN Nw wN m... m O ww m O w wO Ow Ow. wN N... E Q. N _ _ o m2 E. 5 mm m Om wN Ow. . . .. N w N O m NO OO OO NN w. . . . wk w m O m ww. wO ww .wN . . . . w m 1 O .. . . mO Om ww. ON Mm w. MM . w... M w... mm M“ w.” a . . . . ww Ow. Om NO . O N m O O m Om Ow mw. w.w m m... om K . m. a. N m o o m w» mm. “a m: m Ow Ow Ow m M... N O ww. Om NO mw m Ow Ow OO . . . . .. Ow Ow O w Ow. Nm ww ww OO mw mw. . .. . . . w. Ow N w m mw. OO NO Ow wO ww Ow. . ......Ow m. w O mww. hO NO Nw mmm wm wk . . . .. mw O w O D Ow. OO NO ww wO Ow Ow. . . O O m N O mOO wO Ow. . Ow Ow mN 5 . m m w m m O m» Om OO . .O Om Z Om . . w N O w m ww. Nm wO Iw E Nw Nw. . . . w. O N m . m Ow. NO wO . .w. ww mN mO . m w w N m Nw. wm wO . .O m Om mN wm . O N N w OO mw wO . m m wm Ow OO . m. m w O . . . Om w.w mO . .w Mm m N m w Q Om wm w.O . O . .. o is s s 4.. w . . . % w N N m.ww. wm OO _.w $2 . . . w w O Ow. mO OO . ON mm ON Ow. . . N m. N w mw mO wOw . . %N in wOw ...24...2T..2 w w w... w w“ w m w w w. w w ..._i...2_...2 l. m m m. m m m u. m. W w. m. m 2.5 hfiuinzww opsfifiomEow. .w.o==$:oU|wow._ow cowfifincoU .w ~28. 30 TEXAS AGRICULTURAL EXPERIMENT STATION. 3% d 15.5 .m m . F. mm w» m . . . o m» m. Q sm mam. mm w“. fi m Q o w“. ww wx 6m mm om ow . . . 2 w m o m» mm mm . hm mw i m.» . 2 w m o m» 8 ww ..wm .mw mfi m» . 2 I m o . m. mm S mm .mm m mw 3 m“. . m m C w . o ww wm mw .mm mww wm C. I m . o 5 mm E Am m? wm. E ... w w . fl . m6» mm 2 Iom mkw mw w“. . m w . _ ... m w.» E mw Xi m mm mm. m» . . 2 m H Q w» ww 9.. . M: mo mw E . . . 2 w . . m o m. m.» E Hm .2 9?. .3 R. . m w v . m H 2a wm. E T3 mm mm w» . h w _ 2 mm R. ...? m .9“. .5 3. . . . o . . . w ~ m. mm m“. .3 mmm mm mh .. . w m o Q . m. 9. mm w» . .2 m .8 hw ww . . w .. . m fi o m M6 3 E. .m~ . - . . m . . . w o . . . Mm WM Mm . .. my. a M o 5% m W» a mm mm m» . w O w m o 9mm ww $ . Um mw m: we m m w w m o m .3 F. E . w .3 mm w» . > w m Q a 9% E E :> m mw C Ma .. . m I _ o m mm ww w“. .w_m_~.~a< 9 9 9 g P: C. C. C: n: g 532 .52 i .532 we m. m m mm M _ W W. W W Qaow/l .52 _ Raw/H n. ... u. u. u. u. u. u. u. P dfiwQ 0 _ _ %SUMESE . . vii-WSQEQP wonefinoUulwwivw comfifionow A 01.1w? THE COTTON OR MELON LOUSE. 31 ‘flTlcN Jun Feb Mar Apr y Aug Oct Nov Dec / Qiiitl: n n u u! n u a u u u \l Q '=~l=l=n=:===z Figure 3. Succession of Generations in Cotton or Melon Louse n 32 TEXAS AGRICULTURAL EXPERIMENT STATION. Number of Generations. On March 25, 1916, a study was started on the number of successive generations of this species, and this work was continued for exactly one year without a break. For this work cotton was used for the host; and it is well that this selection was made, for the species will not persist well on any other host for an entire year. The cotton plant will with- stand more unfavorable conditions than any of the other hosts, and the infestation was maintained with ease on cotton in the insectary for months when the host was not present in the fields, that is, from Novem- ber to April. _ No sex forms ever appeared on the plants in the cages. In only one generation, the third, did an alate female develop in the cage. The generation series given in Table I is of the first born individ- uals, and consequently it gives only the maximum number of genera- ' tions that may occur in the period of twelve months. There will nat- urally be a variation in the number of generations, even in the same locality, from year to year, as climatic conditions vary. These experi- ments were conducted out of doors during the period that was free from killing frosts,—March 15 to November 1. During the remainder of the year the cages were maintained _in the insectary. The conditions of temperature and humidity were recorded by the hygro-thermograph. In the period of exactly one year, fifty-seven generations were born. In this same period, fifty-one generations completed their life cycle. Table 2. Line of Generation =1 w '-~ .2 e 2° s E 3g _ ‘SQ 2 9‘ a >1 Q23 Date of Date of 131-: >1 3; Date of Q S Date of Flrst Age, Last 3E T, 2 >1 >< h Death 7;, 3 Birth Born Days Young 3.5: +8 s; a g a - ~15 8 CG {-1 <2‘ F Mar. 25. . . . . A ril 3. . . 9 April 23. . . 2O 75 3.7 + 12 April 24. 3O April Aiiril15... 12 May 3... 18 62 3.4+ 4 May 4 31 Aprll15. . . . . April 251‘. . 10 May 2. . . 7 17 2.4+ 3 May 3. 18 A r1125...“ ay 5... 10 May 23... 18 51 2.8+ 4 May 24. 29 ay . . . . . ay 12 May 26. . 14 46 3.2+ 4 May 27. 22 ay 12. May 21 10 June 1. . 11 4O 3.6+ 4 June 2. 21 May 27. .. .. June 8 July 3. . 29 146 - 5.0 9 July 4. 38 May 21. . . . . May 27 6 June 26. . 30 117 3.9+ 8 June 27. 37 June 4... . . June g - gupe 23- - 13? 1g Jllpe 2g 21 June 8.....June13 11y -- - 11y - June 13... . . June 17* 4 June 23. . 6 O 5.0 7 June 24. 11* June 1s. June 22 4 July s.. 1e 7e 4.1+ 1o July 9 21 June 22..... June 29 7 July 8.. 9 24 2.7+ 5 July 9. 24 June 29... .. July 6 7 July 22.. 16 49 3.0 10 July 23. 26 July . . . .. July 11 5 July 22. . 11 51 4.6" 8 July 23. 17 July 1l..... July 16 5 July 27. . 11 59 5.3-- 9 July 28 17 July 1e..... July 2o 4 Aug. 15.. 2e 13s 5.3" 11 Aug. 1e 31 July 20..... July 25 5 Aug. 1.. 7 45 6.4—- 10 Aug. 3. 13 July 25. . . . . July 29 4 Aug 17. . 19 71 3.6+ 12 Aug. 18. 24 July 29, _ _ _ _ Aug 5 Aug 20. . 17 75 4.4 -l- 1O Aug. 21. 23 Aug. 3. Aug 8 5 Sept 1.. 24 85 3.5" 11 Sept. 2 3O Aug. s. Aug 15 7 Sept 4.. 2o 72 3.6» 10 Sept. 5. 2s Aug. 15. . . .. Aug 18 3 Sept 12. . 25 84 3.4" 6 Sept. 13. 29 Aug. 18. . . . . Aug 3O 12 Sept 18. . 19 o4 2.3-- 4 Sept. 19. 31 Aug. so. . Sept 5 2 sfpt 22.. g3 g3 -— é gem. 2g». Se t. 5.....Set 9 ct .. .." Ct- - seiit. 9..... seiit 1s 4 om; 23.. 41 94 2.2-- 5 Oct. 24. 45 Sept 13..... Sept 18 5 Oct 26.. 38 132 3.4" 9 Nov. 6. 54 Sept. 18. . . . . Sept 24 6 Nov 1. . 37 129 3.4" 9 Nov. 7. 5O Sept. 24. . . . . Oct. 1O Nov 3. . 3O 96 3.2" 6 Nov. 12. 49 Oct Oct. 10 6 Oct 30.. 20 89 4.4-- 10 Nov. 11. 38 Oct 10. . . . . Oct 15 5 Nov 12. . 28 99 3.5 —— 1O Nov. 25. 46 Oct. 15..... Oct 21 6 Nov 8.. 18 8O 3.3" IO Nov. 29. 45 Oct. 21. Oct 30 9 Nov 10.. 11 72 6.5" 1O Nov. 30. 40 THE COTTON 0R MiiLoN LOUSE. o Table 2.—Line of Generations—Continued. In H-i .5 a 2° a 3= *-’ :1 o. E >.9. gm o >> aw Date of Date of "Q"U >1 {'5}, g5 Date of Q 5 Date of First Age, Last OE. -—- <° >, ... Death - ° B. h L, q} L4 N H <1 i! irth Born Days Young 0.0 +-= w =° N u, --> Q 65“ é £9 2 °~ i“ Ont 30. . . . . Nov 4* 4 Nov. 7. . 44 14 13 Nov. 8. 9* Nov Nov 11 7 Dec. 5.. 24 116 4.5+ Dec. 11. 37 Nov 11. . . . . Nov 2O 9 Dec. 6. . 16 98 6.1 + 10 Dec. 25 43 Nov. 20. . . .. Nov 28 8 Dec. 15. . 17 76 4.4+ 11 Dec. 29 39 Nov. 28. . . . . Dec 6 Dec. 27. . 23 8 3.4+ 10 Jan. 3 36 Dec 4... . . Dec 13 9 Jan. 11. . 29 126 4.3+ 1O Jan. 29 56 Dec 13..... Dec 1 8 Jan. 8.. 18 68 3.7+_ 11 Jan. 11 29 Dec 21... .. Dec 26* 5 Jan 6. . 11 69 5.9 + 12 Jan. 17* Dec 26. . . . . Jan 1* 6 Jan 20. . 18 103 5.7 + 20 Jan. 21 26* Jan. Jan. 6 Jan 9.. 27 105 3.8+ 10 Jan. 31 30 Jan. . . . .. Jan. 17* 10 Feb. 8. . 22 9 4.4+ 10 Feb. 10 34* Jan 17. . . . . Jan 24 7 Feb 15. . 22 97 4.4+ 10 Feb. 18 31 Jan 24. . . .. Jan 28 4 Feb 10. . 13 53 4.0 6 Feb. 13. Jan 28. . . . . Feb 4* 7 Feb 15. . 11 52 4.7 + 9 Feb. 17. 20* Feb Feb 9 5 Mar 1.. 20 95 3.7+ 11 Mar. 3 27 Feb 9... .. Feb 16 7 Mar 8. . 20 97 4.8+ 12 Mar. 11 30 Feb 16. . . .. Feb 20 4 Mar 14. . 22 88 4.0 11 Mar. 18. 30 Feb 20. . . . . Feb 26 6 Mar. 25. . . 27 53 1.8 + 7 Mar. 27. 35 Feb 26..... Mar 3 5 April 6... 29 114 3.4+ 10 April 7... 40 Mar. 3. . . . . Mar 6 Mar. . . . 20 86 4.3 + 15 April 13. .. 41 Mar Mar 16 7 April 16... 31 114 3.5+ 11 April 18... 40 Mar. 16. . . . . Mar 4 8 April 20. .. 27 154 5.6 + 11 April 27. .. 42 Mar. 24. . . . . Mar 30* 6 April 8. . . 9 63 7.0 8 April 9. . . 16* Mar. 30. . . . . April 8 9 April 25. . . 17 90 5.2 + 7 April 26. . . 27 April 8. . . . . April 16 8 April 26. . . 10 86 8.6 + 11 April 27. . . 19 April 16. . . . . April 22* 6 April 25. . . 3 36 12.0 13 April 26. . . 10* April 22. . . . . April 26* 4 April 27. . . 1 4 4.0 3 April 28. . . 6* ‘t-Alate female. *—Incomplete record. Table 3.-—Age at which Females begin Reproducing. _ Period, Mean Mean Date of Birth Date of First Born Days Temp. - Hum. 1916 . Mar 25 . . . . . . . . . . . . . .- . . . . . . April ‘3 . . . . . . . . . . . . . . . . 73 0 50.1 April 3 . . . . . . . . . . . . . . . . . . . . April 15 . . . . . . . . . . . . . . . . 12 77.4 54.2 April 15 . . . . . . . . . . . . . . . . . . . . April 25 . . . . . . . . . . . . . . . . 10 84.4 52.8 April 25 . . . . . . . . . . . . . . . . . . . . May . . . . . . . . . . . . . . . . 10 79.4 53. 3 May- 5 . . . . . . . . . . . . . . . . . . .. May 12 . . . . . . . . . . . . . . .. 91.0 58.7 May 12 . . . . . . . . . . . . . . . . . . . . May 21 . . . . . . . . . . . . . . .. 10 77.8 50.3 May 21 . . . . . . . . . . . . . . . . . . . . May 27 A . . . . . . . . . . . . 6 94.2 68.7 ay 27 . . . . . . . . . . . . . . . . . . .. June . . . . . . . . . . . . . . .. 8 78.0 44.8 June 4 . . . . . . . . . . . . . . . . . . .. June . . . . . . . . . . . . . . .. 4 87.3 47.6 June 8 . . . . . . . . . . . . . . . . . . .. June 13 . . . . . . . . . . . . . . .. 5 85.5 53.1 June 13 . . . . . . . . . . . . . . . . . . . . June 7 . . . . . . . . . . . . . . .. 4 83.5 54.3 June 18 . . . . . . . . . . . . . . . . . . . . June 22 . . . . . . . . . . . . . . .. 4 83.7 52.0 June 22 . . . . . . . . . . . . . . . . . . .. June 29 . . . . . . . . . . . . . . .. 7 89.1 50.3 June 9 . . . . . . . . . . . . . . . . . . .. J y 6 . . . . . . . . . . . . . . .. 7 87.0 59.3 July 6 . . . . . . . . . . . . . . . . . . .. July 11 . . . . . . . . . . . . . . .. 5 89.7 59.2 July 11 . . . . . . . . . . . . . . . . . . .. July 16 . . . . . . . . . . . . . . .. 5 90.1 64.1 July 16 . . . . . . . . . . . . . . . . . . . . July 20 . . . . . . . . . . . . . . .. 4 91.0 61.3 July 20 . . . . . . . . . . . . . . . . . . .. July 25 . . . . . . . . . . . . . . .. 5 89.4 64 9 July 25 . . . . . . . . . . . . . . . . . . .. July 29 . . . . . . . . . . . . . . .. 4 85.2 71 6 July 29 . . . . . . . . . . . . . . . . . . . . Aug . . . . . . . . . . . . . . .. 5 84.6 69.2 Aug. 3 . . . . . . . . . . . . . . . . . . .. Aug 8 . . . . . . . . . . . . . . .. 5 _86.1 75.3 Aug. 8 . . . . . . . . . . . . . . . . . . . . Aug 15 . . . . . . . . . . . . . . .. 7 85.5 69. 1 Aug. 15 . . . . . . . . . . . . . . . . . . . . Aug 18 . . . . . . . . . . . . . . . . 3 84. 1 71.3 Aug. 18 . . . . . . . . . . . . . . . . . . . . Aug 30 . . . . . . . . . . . . . . .. 12 84.4 68.3 Aug. 30 . . . . . . . . . . . . . . . . . . .. Sept 5 . . . . . . . . . . . . . . .. 6 85.3 69.6 Sept. 5 . . . . . . . . . . . . . . . . . . .. Sept 9 . . . . . . . . . . . . . . .. 4 86.8 68.6 Sept. 9 . . . . . . . . . . . . . . . . . . .. Sept 13 . . . . . . . . . . . . . . .. 4 86.6 71.5 Sept. 13 . . . . . . . . . . . . . . . . . . .. Sept 18 . . . . . . . . . . . . . . .. 5 82.0 65.7 Sept. 18 . . . . . . . . . . . . . . . . . . . . Sept 24 . . . . . . . . . . . . . . .. 6 77.5 62.0 Sept. 24 . . . . . . . . . . . . . . . . . . .. Oct 4 . . . . . . . . . . . . . . .. 1O 90.7 57.9 Oct 4 . . . . . . . . . . . . . . . . . . .. Oct 10 . . . . . . . . . . . . . . .. 6 80.1 68.2 Oct 10 . . . . . . . . . . . . . . . . . . . . Oct 15 . . . . . . . . . . . . . . .. 5 77.6 69.4 Oct 15 . . . . . . . . . . . . . . . . . . .. Oct 21 . . . . . . . . . . . . . . .. 6 70. 1 76.2 Oct 21 . . . . . . . . . . . . . . . . . . . . Oct 30 . . . . . . . . . . . . . . .. 9 59.5 65.1 Oct. 30 . . . . . . . . . . . . . . . . . . . . Nov . . . . . . . . . . . . . . . . 5 69.0 64.5 Nov 4 . . . . . . . . . . . . . . . . . . .. Nov 11 . . . . . . . . . . . . . . .. 7 70.7 67.1 34 Texas AGRICULTURAL EXPERIMENT STATION. Table 3.—-Age at which Females begin Reproducing—Continued. _ _ Period, Mean Mean Date of Birth Date of First Born Days Temp. Hum, 1916 Nov. 11 . . . . . . . . . . . . . . . . . . .. Nov. 20 . . . . . . . . . . . . . . .. 9 53.4 67.6 Nov. 20 . . . . . . . . . . . . . . . . . . . . Nov. 28 . . . . . . . . . . . . . . . . 8 56.0 72.7 Nov. 28 . . . . . . . . . . . . . . . . . . .. Dec. 4 . . . . . . . . . . . . . . . . 6 63.7 65,2 Dec. 4 . . . . . . . . . . . . . . . . . . .. Dec. 13 . . . . . . . . . . . . . . .. 9 58.8 60.7 Dec. 13 . . . . . . . . . . . . . . . . . . . . Dec. 21 . . . . . . . . . . . . . . .. 8 52.2 64.5 Dec. 21 . . . . . . . . . . . . . . . . . . .. Dec. 26 . . . . . . . . . . . . . . .. 5 47.8 62.5 Dec. 26 . . . . . . . . . . . . . . . . . . .. Jan. 1 . . . . . . . . . . . . . . .. 6 59.4 62.8 1917 an. 1 . . . . . . . . . . . . . . Jan. 7 . . . . . . . . . . . . . . .. 6 63.6 72.7 Jan. 7 . . . . . . . . . . . . . . . . . . .. Jan. 17 . . . . . . . . . . . . . . .. 10 59.0 54.0 -Jan. 17 . . . . . . . . . . . . . . . . . . .. Jan. 24 . . . . . . . . . . . . . . .. 7 70.4 53.9 Jan. 24 . . . . . . . . . . . . . . . . . . .. Jan. 28 . . . . . . . . . . . . . . .. 4 75.2 48.0 Jan. 28 . . . . . . . . . . . . . . . . . . .. Feb. 4 . . . . . . . . . . . . . . .. 7 74.3 48.5 Feb. 4 . . . . . . . . . . . . . . . . . . . . Feb. . . . . . . . . . . . . . . .. 5 71.7 44.0 Feb. 9 . . . . . . . . . . . . . . . . . . . . Feb. 16 . . . . . . . . . . . . . . .. 7 59.8 48.4 Feb. 16 . . . . . . . . . . . . . . . . . . . . Feb. 20 . . . . . . . . . . . . . . .. 4 78.7 48.6 Feb. 20 . . . . . . . . . . . . . . . . . . .. Feb 26 . . . . . . . . . . . . . . .. 6 82.7 41.1 Feb. 26 . . . . . . . . . . . . . . . . . . .. Mar . . . . . . . . . . . . . . .. 5 77.6 51.6 Mar. 3 . . . . . . . . . . . . . . . . . . .. Mar 9 . . . . . . . . . . . . . . .. 6 67.2 51.0 Mar. 9 . . . . . . . . . . . . . . . . . . . . Mar 16 . . . . . . . . . . . . . . .. 7 73.7 73.3 Mar. 16 . . . . . . . . . . . . . . . . . . .. Mar 24 . . . . . . . . . . . . . . .. - 8 61.1 50.0 Mar. 24 . . . . . . . . . . . . . . . . . . . . Mar . . . . . . . . . . . . . . . . 6 70.8 37.8 Mar. 30 . . . . . . . . . . . . . . . . . . .. April 8 . . . . . . . . . . . . . . . . 9 70.9 47.3 ‘ April 8 . . . . . . . . . . . . . . . . . . .. April16 . . . . . . . . . . . . . . .. 8 63.4 53.0 April 16 . . . . . . . . . . . . . . . . . . . . April 22 . . . . . . . . . . . . . . . . 6 69.3 59.7 April 22 . . . . . . . . . . . . . . . . . . . . Apr1l26 . . . . . . . . . . . . . . . . 4 70. 8 46.3 Age art Which Females Reproduce. 1n Table 3 aregiven the records showing the age of each female ob- served when the first young was produced. This period varies with tem- perature and humidity conditions. In the table are given the mean temperature and the mean humidity for the period. A single high or a single low temperature may eiTect the duration of this period. The shortest period of three days occurred August 15 to 18, 1916, with a mean temperature of 84.1 degree F. and a mean humidity of 71.3 per cent. The period 0t four days occurred in ten generations with a mean temperature of 82.9 degrees F., and a mean humidity of 56.9 per cent. The longest period of 12 day's occurred from April 3 to 15, 1916, with a mean temperature of 77.4 degrees F. and a mean humidity of 54.2 per cent, and again from August 18 to 30, 1916, with a mean temperature of 84.4 degrees F. and a mean humidity of 68.3 per cent. Reproductive Period. Climatic conditions exert as great an influence upon the length of the reproductive period as they do upon the other details of the aphid life history. The records made on this phase of the life history are shown in Table 4. The shortest period shown, 9 days, with a mean temperature of 85.9 degrees F. and a mean humidity of 59.6 per cent, is somewhat abnormal as the female reproduced only twenty young. The next short- est period, 11 days, occurred four times when the full period was ob- served. The mean temperature during these perio-ds was 84.0 degrees F., and the mean humidity was 60.2 per cent. The average total young of these generations was 58.2, which is slightly below the average num- ber of young produced. The longest reproductive period, 41 days, oc- curred from September 13 to October 23, 1916, with a mean temper- THE CoTroN OR AIELoX LOUSE. attire of 73.6 degrees F, and a nieairhuiniclity of 65.1 per cent. The total young produced by this generation was 94. The average repro- duction period of all females observed in this Work was 21.4 days. Table 4.—Reproductive Period and Young Produced. Repro- i Date of Date of ductive Mean Mean Gener- Total Average First Born Last Young Period, Temp. Hum. ation Young Per Days Day April 3 . . . . . . .. April 23 . . . . . . .. 20 69.5 51.5 1 75 3.7 April 15 . . . . . . .. May . . . . . . .. 18 75.0 47.5 2 62 3.4 April 25 . . . . . . .. May 2 . . . . . . .. 7T 73.3 47.0 3 17 2.4 May 5 . . . . . . .. May 23 . . . . . . .. 18 82.8 51.8 4 51 2.8 May 12 . . . . . . .. May 26 . . . . . . .. 14 78.0 53.9 5 46 3.2 May 21 . . . . . . .. June 1 . . . . . . .. 11 82.6 54.6 6 40 3.6 une 4 . . . . . . .. July.- 3 . . . . . . .. 29 88.2 51.9 7 146 5.0 May 27 . . . . . . .. June 6 . . . . . . .. 30 85.2 51.4 8 117 3.9 une 8 . . . . . . .. June 25 . . . . . . .. 17 83.9 53.8 9 75 4.4 June 13 . . . . . . .. July 2 . . . . . . .. 19 86. 1 52.4 10 101 5.3 June 17 . . . . . . .. June 23 . . . . . . .. 6* 84.6 52.1 11 3O 5.0 June 22 . . . . . . .. July . . . . . . .. 16 87.2 55. 5 12 76 4.7 June 29 . . . . . . .. July . . . . . . .. 58.9 59.6 13 24 2.7 July 6 . . . . . . .. July 22 . . . . .., 16 90.3 62.0 14 49 3.0 July 11 . . . . . . .. July 2 . . . . . . .. 11 90.1 63.3 15 51 4.6 July 16 . . . . . . .. Julyi27 . . . . . . .. 11 89.4 64.2 16 59 5.3 July 20 . . . . . . .. Aug. . . . . . . .. 26 78.9 64.0 17 138 5.3 July 25 . . . . . . .. Aug. 1 . . . . . . .. 7 84.5 71.2 18 45 6.4 July 29 . . . . . . .. Aug. 17 . . . . . . .. 19 76.4 65.8 19 71 3.6 Aug 3 . . . . . . . . Aug. 20 . . . . . . .. 17 75.4 62.4 20 75 4.4 Aug . . . . . . .. Sept. . . . . . . .. 24 77.5 63.5 21 85 3.5 Aug 15 . . . . . . .. ept. . . . . . . .. 20 84. 5 69.2 22 72 3.6 Aug 18 . . . . . . .. Sept. 12 . . . . . . .. 25 85.2 69.2 23 84 3.4 Aug 30 . . . . . . .. ept. 18 . . . . . . .. 19 89.9 65.3 24 54 2.3 Sept 5 . . . . . . . . Sept. 25 . . . . . . . . 20 82.7 66. 6 25 62 3. 1 Se!) . . . . . . . . Oct. . . . . . . . . 28 79.4 63.3 26 80 2.2 Sept 13 . . . . . . .. Oct. 23 . . . . . . .. 41 73.6 65. 1 27 94 2.2 Se t 18 . . . . . . .. Oct. 26 . . . . . . .. 38 70.3 63.5 28 132 3.4 S pt 24 . . . . . . .. Nov. 1 . . . . . . .. 37 73.6 68.0 29 129 3.4 4 . . . . . . .. Nov. 3 . . . . . . .. 30 73.0 69.1 30 96 3.2 Oct 1O . . . . . . .. Oct. 30 . . . . . . .. 20 70.1 71.4 31 89 4.4 Oct 15 . . . . . . .. Nov. 12 . . . . . . .. 28 66.0 65.7 32 99 3.5 Oct 21 . . . . . . .. Nov. . . . . . . .. 18 67.3 64.8 33 80 3.3 Oct 3 . . . . . . .. Nov. 10 . . . . . . .. 11 65.4 60.7 34 72 6.5 /Nov 4 . . . . . . .. Nov. 7 . . . . . . .. 3* 71.0 63.3 35 44 14.0 Nov 11 Dec. 5 . . . . . . .. 24 57.7 68.9 36 16 4. 5 Nov 20 . . . . . . .. Dec. 6 . . . . . . .. 16 61.0 70.0 37 98 6.1 Nov 28 . . . . . . .. Dec 15 . . . . . . .. 17 60.2 67.7 38 76 4.4 Dec . . . . . . .. Dec 27 . . . . . . .. 23 54.4 64. 6 39 80 3.4 Dec 13 . . . . . . .. Jan 11 . . . . . . .. 29 56.6 45.0 40 126 4.3 Dec 21 . . . . . . .. Jan. 8 . . . . . . .. 18 57.3 65.7 41 68 3.7 Dec 26 . . . . . . .. Jan. 6 . . . . . . .. 11* 68.0 68.8 42 69 5.9 1917 an 1 . . . . . . .. Jan. 20 . . . . . . .. 18* 58 9 66.0 43 103 5 7 Jan 7 . . . . . . .. Jan. 29 . . . . . . .. 7 64 8 58.2 44 105 3 8 Jan 17 . . . . . . .. Feb. . . . . . . .. 22* 72 4 46.8 45 99 4 4 Jan 24 . . . . . . .. Feb. 15 . . . . . . .. 22 74 7 45.2 46 97 4 4 Jan 28 . . . . . . .. Feb. 10 . . . . . . .. 13 73 6 42.5 47 53 4 0 Feb 4 . . . . . . .. Feb. 15 . . . . . . .. 11* 74 7 46.1 48 52 4 7 Feb 9 . . . . . . .. Mar. 1 . . . . . . .. 20 79 9 46.6 49 75 3 7 Feb 16 . . . . . . .. Mar. 8 . . . . . . .. 20 76 5 45.4" 50 97 4 8 Feb 20 . . . . . . .. Mar. 14 . . . . . . .. 22 75 3 50.0 51 88 4 0 Feb 26 . . . . . . . . Mar. 2 . . . . . . .. 27 65 8 50.9 52 53 1 8 Mar 3 . . . . . . .. April 6 . . . . . . .. 29 87 1 56.6 53 114 l 3 4 Mar 9 . . . . . . . . Mar. . . . . . . . . 20 72 4 48.1 54 86 4 3 Mar 16 . . . . . . .. April 16 . . . . . . .. 31 69 3 47.7 55 114 3 5 Mar 24 . . . . . . . . April 20 . . . . . . . . 27 68 7 43.8 56 154 5 6 Mar. 30 . . . . . . . . April 8 . . . . . . . . 9* 70.9 47.2 57 63 7 0 April 8 . . . . . . . . April 25 . . . . . . . . 17 66.7 53.6 58 90 i 5 2 April 16 . . . . . . . . April 26 . . . . . . . . 10 69.9 54.3 59 86 ‘ 8 6 April 22 . . . . . . . . April 25 . . . . . . . . 3* 70.1 43. 5 60 36 1 2 April 26 . . . . . . .. April 27 . . . . . . .. 1* 74.5 56.5 61 . 4 f 4 0 $4 l T—Ala' e ‘emale. *—-Incomplete record. 36 TEXAS AGRICULTURAL EXPERIMENT STATION. Total Young Produced. The number of young produced varies greatly with the generation. The greatest number of young produced by one female was 154, over a period of 29 days. The mean temperature of this period was 68.7 de- grees F., and the mean humidity was 43.8 per cent. The least number of young produced by a single female was 24, during a period of 9 days. The mean temperature of this period was 85.9 degrees F., and the mean humidity was 59.6 per cent. It cannot be said that the total number of young produced is less with lower temperatures, for examples taken from the table show that there is no correlation. For instance, the seventeenth generation produced with a mean temperature of 78.9 de- grees 138 young, while the succeeding generation produced, with a mean temperature of 84.5 degrees F., only 45 young. Again, in the twenty- seventh and twenty-eighth generations the number of young produced was high, with a mean temperature of 70.3 and 73.6 degrees F., respec- tively. In the, fifteenth and sixteenth generations the number of young produced was very low, but the mean temperature was 90.7 and 89.4 de- grees F., respectively. Furthermore, the high temperatures do not reduce the number of young produced. The average number of young pro- duced by a female, of the individuals observed in this Work, was 84.4. Average Alzmtber of Yottng Daily. As shown in Table 4, the average number of young produced is not apparently controlled by any of the factors recorded. There is no cor- relation of this number with the total young produced or the length of the reproductive period. For instance, in the sixteenth and seven- teenth generations the average young produced daily is the same; whereas the total young produced approach both extremes. Again the least average did not occur with the shortest period of reproduction or the smallest total young produced. The average number of young produced daily, according to months, show smaller numbers in August, September, and in May. Here again there is an absence of any positive correlation of this number with the other factors recorded. These results are shown in Table 5. Table 5.-—Average Young Produced Daily. Mean Mean ’ Month Young Temperature Humldity 1916 April . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 3.0 73.3 48.3 ay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.7 79.2 52.9 June . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 4.4 85.7 51.4 July . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 4.7 89.5 62.0 August . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2.8 85.3 76.8 September . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.3 78. 8 67. 3 October . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 4.3 72.6 67.7 November . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4. 4 60. 7 68. 1 December . . . . . . . . . . . . . . . . . . . . . . . . . _ . . . . . . . . . . 5.6 55 8 63.9 1917 January . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4. 6 66 60. February . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4. 5 76.8 43 8 March . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 3.7 79.3 49 1 April . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3. 9 68. 52 THE COTTON 0R MELON LOUsE. 37 Longevity. In Table 2 is shown the length of each generation observed’. The longest period. consumed by a single generation was 56 days, from De- cember ll, 1916_, to January 29, 191.7’. The shortest period was 13 days, from July 20, 191b, to August 3, 1916. The number of young produced by this generation was the least of any of the apterous females. The average longevity of adult life of all the generations observed was 32.1 ays. Rate 0f Increase. A reference to the average number of young produced, the average reproductive period, and the average longevity, will enable one to gain an idea of how readily this species may increase. The average period of maturity was 6.5 days, and an average number of 84.4 young were produced over an average period of 21.4 days. ' Efiect of Temperature on De/velopmenlt. This species is susceptible to the effects of temperature during all stages of its life history. The effects of the low temperatures could not be determined for this species, as it has been done for other series, for during the coldest portions of the yrear the generation-series work was conducted in the insectary. During the spring and the fall months, when daily temperatures fluctuate, there was a corresponding change in the daily young produced. Also, low temperatures during a twenty- four hour period had. more effect on the daily young produced than did the high temperature of the same period. In the cages of the generation-series experiments, temperature did not affect the development of alate females. As only one alate female de- veloped in the series, it is impossible to dis-cuss the factors influencing the development of such forms. During the warmest period of the year the development of all stages is retarded. It is very evident that the maximum temperature condi- tions are not the optimum conditions for the life activities. The period ‘ of extereme high temperature usually extends throughout the months of August and September. Reference to Table I will show that during this period the reproduction was less than during the preceding or suc- ceeding months. VIVIPAROUS DEVELOPMENT. The normal form of reproduction in the cotton or melon louse in Texas is asexual throughout the entire year. At no time in cage studies or field observations, has a sex form of this insect been observed. Field observations were made on this plant louse within the extreme bounda- ries of. the State. It is interesting that the sex forms of this species have never been found at any latitude in the United States. SEASONAL HISTORY. Detailed records were made on this insect at College Station during a period of two years. The experimental garden. contained all the com- mon host plantsiof this louse, and during the second season the common \- 38 “Perms AGRICULTURAL EXPERIMENT STATION. host plants were planted at successive dates. These studies were sup~ plemented with field cages. During the later spring of 1916 the host. plants were grown 1n the insectary, and these were left t0 natural in- festation by released plant lice from the cages. Again, in the fall and ear y winter all these host plants were available in the insectary for natural infestation. 1916. Insectaojy: As early as January 11 lice were noticed 0n seedling cot- ton which had but the second pair of leaves. This infestation was just starting; so most of the lice present were winged females. At this time some old watermelon vineswere very heavily infested. This was un- usual as there had been no heat in the insectary up to within a short time previous to this date. The xvinged females were present in great numbers on the watermelon. At this date seedling cucumbers were in- Rested; the lice being on the growing tip and second leaves. This in- festation was Well established at that time. The infestation had just started on squash seedlings. A few days later an artificial transfer of lice’ from the heavy infestation on watermelon to cotton was attempted. For this purpose both the winged and the Wingless forms were used, but t-ne lice refused to colonize in both cases. During the remainder of January and throughout February the in- festation increased on cotton. The old watermelon vines were killed and on March 9 seedling plants were again available. However, these were not infested with lice. Muskmelon seedlings were also available at this time, but they were not infested. Cucumber plants which were growing adjacent to the melons were heavily infested. At this time a row of young okra plants was heavily infested. Two weeks later the lice were very abundant on all cotton in the insectary. This infestation was made up of a large proportion of winged individuals. At this time an infestation was well established on water- melon seedlings but the muskmelon seedlings adjoining were not in- fested. The o-kra infestation continued very heavy. A large squash plant some distance from cotton was very heavily infested, and the plant died in a few days. At the end of the next week the infestation on cotton had decreased slightly. On watermelon the infestation had increased, and the plants were about killed. The infestation was still very heavy on okra, but these plants seemed to be able to withstand the attack of a large num- ber of lice. At this time lice were first observed in small numbers on cowpeas. On one eggplant three Wingless lice were observed, but no young were found on this host at any time. In four days there were no lice on this host. One Wingless and two winged lice were found on a sweet pepper plant. Two young ones were found on the following day, and these matured and reproduced. A week later the infestation was dwell established. However, most of the lice developed into the winged form and left the plant. Lice were observed on gourd, but the young present at this time did not mature and reproduce. The observations in the insectary were closed on April 1. time the infestation on all hosts was decreasing, which fact was prob- At this . ably due to the poor growing condition of most of the plants. It was. almost two months later when observations were begun in the field. fireqoasu] ‘II 913M [Blank Page in Original Bulletin] THE OorToN on lNIELoN LOUSE. 39 During this interval the lice were not observed on any Weeds in the vicinity of the field or insectary. F icld : On May 2-1 lice were first observed on cotton that was from six to ten inches high. The infestation was Well scattered and con- sisted of Wingless lice. At this seaso-n the Winged lice develop in a larger proportion than later; so that many plants are infested at about the same time. No lice Were observed on watermelons Which Were growing adjacent to the cotton. The muskmelons were also not in- fested at this date. On the cucumbers the infestation Was just start- ing. No infestation Was found on okra, cowpea,.squash, and pumpkin at this date, although these host plants were growing very close to the infested plants. v On the following day the infestation on cotton had increased mate- rially. Still there Was no infestation on watermelon and muskmelon. On cucumber the lice were not increasing. On one plant o-f okra there were a few immature lice. The infestation continued to spread on cotton in the experimental garden. In the field the lice were just appearing on cotton on May 26 at which time the winged are abundant. The ‘first lice were observed on watermelon on this date. This plant was only twelve feet from the first infested cotton. The infestation on cucumber did not increase at this time. , Five days later the infestation on cotton had increased so that the small leaves near the top of the plants were almost covered. The winged lice observed on watermelon previously’ did not start an infestation on this host. The infestation on cucumber was slight and well scattered. On okra the lice were Well scattered and were not increasing rapidly. Lice were found on squash for the first time, on May 31, although this host had been growing in the adjoining row to cotton. Lice were present also on pumpkin for the first time. Although infestation continued to increase on cotton, it remained Well scattered on the plants over the field. A large proportion of winged lice existed through the infestation. On June 2 there were no lice on ivatermelon, muskmelon, or cucumber. At this time the okra was be- coming heavily infested. On squash and pumpkin the lice increased, but were well scattered over the plants. From June 5 the lice decreased on all-the cotton in the cages, garden, and field. The same was true on Watermelon, muskmelon, and cucum- ber. During this time the lice increased on okra, squash, and pumpkin. By the middle of June there were but few lice on. cotton, and they were well scattered over the field. At this time the infestation on okra was decreasing, as was the case, on squash and pumpkins. Throughout the latter part of June the light scattered infestation persisted on cotton. During this period a few scattered lice were found on watermelon, musk- melon, and cucumber. The light scattered infestation persisted on squash and pumpkin. During the first half of July the infestation increased slightly on cotton with a very large proportion of winged lice, which was probably to carry much of the infestation to another host plant. During this period a few lice persisted on watermelon, but a large proportion of them were the winged form. On muskmelons the infestation increased 40 TEXAS AGRICULTURAL. EXPERIMENT STATION. during this period to such an extent that a few plants were killed. Con- siderable damage was done t0 the cucumber plants by the increased in- festation during this period. The infestation on okra was very light but persisted throughout this period. Lice were found on cowpeas for the first time during this period. This infestation was light and Well scattered. The infestation on squash and pumpkin was very heavy, but was well scattered and consistent. A light infestation of lice persisted on cotton throughout the last half of July. During this period the proportion of winged lice was very large. No lice were found on watermelon during this period, but many muskmelon vines were killed by the severe infestation. The in- festation was heavy on cucumbers during this period. On squash and pumpkin the infestation gradually decreased. During the first part of August the infestation on cotton increased slightly. The same was true on Watermelon, muskmelon, and cucumber during this period and the plants died about the middle of August. Also the squash and pumpkin plants died, though not from the attack of the lice. Observations during the first half of September showed a few lice on cotton in the field, and in the garden young cotton was more heavily infested than old cotton. At this time there were not many winged lice. The light scattered infestation persisted during the latter part of the month. During the month of October the infestation increased considerably, but it decreased during the first half of November. On _ November 18 a temperature of 28 degrees F. was recorded. Lice were found on the cotton on November 15, but from that date the lice dis- appeared rapidly from the field. At this time most of the lice developed into winged adults. Where cotton ground had been fall-plowed, the lice were found frequently on the exposed tips of the plants, and they persisted on these tips throughout November. On December 8 an ex- amination was made in the field where the cotton stalks were allowed to remain standing. A few lice were found in the lower axils of the plant, in which location they were somewhat protected from the weather. There were some seedling plants in this field, and such plants were often infested with lice. Insectary: In the early fall plantings were made in the insectary of the host plants of this louse. On November '7 lice were found on the young cotton plants that were just forming the second leaves. The watermelon plants were heavily infested with lice at this time, and a ' large proportion of winged lice developed. Young muskmelon plants were killed at this time by the severe infestation of lice. Cucumber plants were infested as early as the middle of October. This infesta- tion increased veryrapidly and all the plants were killed by November ‘T’. Young plants coming up atthis time were heavily infested. The okra was attacked heavily as soon as it came up. The infestation on squash and pumpkin started in October and did not increase rapidly until November '7. Oowpeas were planted next to squash, but the infestation on this host did not begin until the squash was heavily infested. A slight infestation occurred at this time on sweet peppers. TDuring the latter part of November the infestation increased on cotton, and many winged lice developed. By this time the watermelon, Plate III. Seasonal History Cage. (Texas Bulletin 227.) [Blank Page in Original Bulletin] THE OoTroN on‘ hfELoN LoUsE. 41 y fuskmelon, and cucumber plants were killed by the severe infestation. }u okra plants were heavily infested at this time. Squash and i, pkin plants were killed and seedlings Were very heavily attacked this time. Oowpeas were generally infested at this time. The lice g re well colonized on sweet pepper at this time. I 1917. pfFieiZd: On May 23, just one day earlier than last year, lice were sent on cotton in the field. At this time the plants Were very small; "I most cases the second pair of leaves were only developing. The in- i tation was Well scattered over the plants and consisted of Winged lice I d colonies of young. On Watermelon, niuskmelon, and cucumber the j: estation was starting at this date. The large plants were infested, ereas seedlings were not. On this date okra was found heavily in- ted, the lice of the second generation reproducing on seedling plants; ; ash and pumpkin plants was found to be light although general. .-A week later the infestation on cotton was reduced, and a large pro- ‘rtion of the lice present were Winged. The infestation was much avier on the replant cotton. On watermelon, muskmelon, and cucum- ir the lice had almost disappeared since the last date of observation, t the infestation on okra had increased. The infestation just per- p» ted on squash and pumpkin during this period. During June the infestation on cotton decreased so that by June 25 7 lice were found on this host. During the month no lice were found '_~: watermelon, muskmelon, and cucumber. The infestation during this nth decreased on okra and most of the lice were Wingless. No lice re found on cowpea during this entire season. The lice disappeared" tirely on squash and pumpkin during June. At no time were lice ‘erved on eggplant, although it was grown adjacent to the other host nts. ..,iSummar~v: The habits of this plant louse were quite similar during f two- seasons of observation. The infestation started on cotton at ctically the same date and increased for two to three weeks; then it i, reased and persisted throughout the summer. With the coming of ‘fol weather in the fall the-infestation increased for a period and de- iased before the occurrence of the first frost. The infestation on the lcurbits started soon after that of cotton, and the plants died before i excessive heat of the summer. Okra was heavily infested during a.» early summer and a light infestation persisted throughout the sum- During the fall this infestation ‘increased. On squash and pump- ‘l the lice increased slowly and persisted until the extreme heat of mer. There was no fall infestation on these _hosts.. The louse is found on cotton in the field from May 24 toDecember 8. On ' 3 a‘ the lice were present from hla-y 24 to October 1. The infestation ‘cueurbits has been of short duration,-the months of June and July. MIGRATION TESTS. n order that more information might be secured concerning the life tory, alternate food plants, and hibernation of this plant louse, m1- ' infestation was well started. The infestation on three sizes of a s12‘ TEXAS AGRICULTURALIIXPERIMENT STATION. l‘ work the dark form is olive green, and the light form is lemon yell A » gration tests were made. These were conducted in the insectary .1 seedling plants in the usual type of cage. -In all cases the winged ’ were transferred; this form being the usual migrant. The transfer " considered successful if the winged l.ice produced young which mat and reproduced on the new host. In many instances young were p duced by the, winged lice, but for one reason or another such yo s? failed to mature on a host. In the past, the presence of a louse ,1», plant was considered sufficient evidence that this plant was a host. has led to a verylengthy’ list of host plants for several species of i, and such lists are misleading. In this work many times the winged 1' would remain on a plant a day or two before leaving it, without j, ducing any young. With the above mentioned standard of a host p many were included in a list of hosts for this insect. The color va i tion is mentioned in this work, but the full significance of this p, aomena is not fully understood at this. time. For many years _ color variation has been noted, and in the first part of the account 1n, tion was made of the definite existence of the lice color forms. In Cotton. The transfer of lice from cotton was easily successful at any time’; the year, either the dark or the light form. The life history procee without interruption whenever this transfer was made. , During January, 1916, eight transfers of the dark form were pf from watermelon in the insectary. These transfers were all repea y and slight infestation resulted on cotton, although a very large pro, tion of. winged lice developed. In January, 1917, three trials‘ "3 made of this transfer, and a light infestation resulted in one w,‘ On May 18, 1917, a transfer was made of the light form but no yo were produced. \ In January, 1916, two tiransfers were made of the dark form, but young were produced. In October, 191.6, four transfers werema and no young lice were produced. In June, 191.7, a transfer was q of the light form, which did not succeed. _ During January and. March, 1916, five transfers were made of dark form from. cucumber, and no young resulted from any trans, In October a transfer was again made of this form, and a colonizai resulted. In March, 1917, four transfers were made of the dark f0 '1 but no young were produced. In April, 191.7, two transfers of light form were made, but these were not successful. ' if Transfers were made from okra with both forms, and coloniza " resulted in every case, regardless of the time of the year. On c0" ‘only the light form was ever produced. Transfers were made from f, host in_ March and April, 1916, and colonization resulted. Only _. transfer was made from squash. This was with the light. form although young were produced, they never developed. In Decem 1916, a transfer was made of the light form, from pumpkin, n‘ resulted in a colonization. In March, 1917, two transfers were n = of the dark form. In one case colonization resulted. Transfers " made from begonia, of both forms, during the winter, and coloniza ' resulted in every case. 33m H4. Ommm m??? AHmNNm mass: $3 [Blank Page in Original Bulletin] THE CoTToN on lVIELoN LoUsE. 4.3 l/Va-termraion. Transfers were made with both forms from watermelons, and coloni- zation resulted in every’ case, even throughout the Winter in the inseotary. During May, 1916, four transfers of the light form were made from cotton, but no jyoung were produced. This transfer was repeated again in l\larch, 1917, with the same results. During February, 1916, six transfers were made of the dark form from cotton, but no young were produced. During March, 1917, seven more transfers were made of the dark form from cotton, and again no young were produced. Migration may take place at any time from muskmelon and cucumber with either form. Only the dark form was transferred from okra in October, 1916, and hilarch, 1917. Three tests were made, but no young were produced. Only one transfer was made of the light form from cowpea, but no young were produced. During April, 1917, two transfers of light form from squash were made. Colonization resulted in both cases. Both forms Were transferred from pumpkin, but the light form did not colonize. Muskmelort. During the fall of 1916 eight transfers were made of the light form from (zotton, but colonization did not take place in a single instance. -In the spring of 191'?’ four transfers were made of the dark form and’ three of the light form, but no young were produced. Colonization oc- curred in all the transfers from Watermelon at any season. Both forms Were transferred from cucumber, and colonization took place. Only the dark form was transferred from okra, but no young were produced in 4 the four transfers made. Only the light form was transferred from cowpea, and in one case a slight infestation did occur. From squash and pumpkin only the light form was transferred, but colonization took place. Citcumbers. During May, 1916, five transfers were made of the light form from cotton, but there was no colonization in any case. During October seven transfers were made of the light form again, and no young were produced. The dark forms from cotton were transferred eight times during the month of March, 1917, and no infestation resulted. Only the dark form of Watermelon and muskmelon was transferred, but col- onization took place at all times. Transfers of either form from cu- cumber would colonize at all times of the year in the insectary. The dark form was transferred from okra in October, 1916, and colonization - took place. On May 10, 1917, the light form of squash was transferred, and lice colonized on cucumber. From pumpkin the light form was transferred, and. a severe infestation resulted on cucumber. During June, 1916, two transfers were made of the light form of cowpea, but no young were produced. Okra. Both the light and dark forms were transferred from cotton, and colonization resulted in any season. In October, 1916, the dark form of watermelon was transferred, and the lice colonized; but when the 4-1 TEXAS AGRICULTURAL EXPERIMENT STATION. light form was transferred in June, 1917, no young were produced. In November two transfers of the dark form were made from muskmelon, and no lice were produced; but an infestation did result from a transfer of this form in June, 1917. At the same time the light form did not produce. young when transferred. From cucumber the light form was transferred in November, 1916, but no young Were produced. In December, 1916, the dark form was transferred, and young lice were produced, but they‘ did not develop. However, the lice did colonize when the dark form was transferred in March, 1917. The one transfer of light form from cowpea in June, 1916, resulted in an infestation. From squash one transfer was made in May, 1917, of the light form which resulted in an infestation. The dark form of pumpkin was transferred in March, 1917, and young were produced. Cowpea. Transfers were made at all seasons of both forms from cotton which always resulted in a. heavy infestation. The dark form of watermelon was transferred in October, 1916, and a slight infestation occurred, but no young were produced when the transfer was made of the light form in June, 1917. ' During October, 1916, four transfers were made of the dark form from muskmelon, but no young were produced. A few young licc were produced when a transfer of the dark form of cucumber was made, but no young were produced. A slight infestation resulted when the light form was transferred in June, 1.917. Only the dark form of okra was transferred four times in October, 1916, and three times in March, 1917, but no young were produced. A light infestation resulted when the light form was transferred from squash in May, 1917. In December,’1916, no- youngwere produced when the light form was transferred from pumpkin, but in May, 1917, a slight infestation re- sulted. In lVlarch, 1917, the dark form was transferred, and an in- festation was produced. Sgizash. During September, 1916, a transfer from cotton was made with the i‘ light form, which resulted in a severe infestation. The same was true when the dark form was transferred in March, 1917. _The dark form from watermelon was transferred during all seasons, and an infestation resulted each time. No young were produced when the light form was transferred fro-m muskmelon, but when the dark form was transferred an infestation resulted. Only the dark form was transferred from cu- cumber during October, 191.6, and March, 1917, but each produced an infestation. The dark form from okra did not establish on squash, but when the light form was used an infestation resulted. The light form from cowpea was transferred four times during November, 1916, but no young were produced. Both forms from. pumpkin established when- ever transferred. ‘ Pumpkin. Only the light form was transferred from cotton and in each case _ an infestation resulted. Both the dark and the light forms from water- melon established when transferred. From muskmelon both the light THE CorroN OR MELoN LoUsE. 45 and the dark forms were transferred, and in all cases infestation was larodurzed. A normal infestation was produced when the dark form was transferred from cucumber in March, 1916, and when the light form WHS used in Tune, 1917. Only the light form from cowpea established itself When transferred in November, 1916. All transfers from squash established themselves at any time. Gourd. - The light form of cotton was transferred in September, 1916, four times; and young lice were produced, but they did not mature. In December, 191.6, the dark form was transferred from cotton. Again, young lice were produced, but they did not mature. In March, 19.17, the dark form was transferred from watermelon, which transfer re- sulted in an infestation. The dark form Was transferred from cucum- ber in March, 1917', and established on gourd. From okra the dark form was transferred four times, and no lice were produced. An in- festation resulted when the dark form was transferred from pumpkin. No artificial migration from any source was successful on eggplant, sweet pepper. nasturtium, garden bean, or soy bean. Summary. From the above notes on artificial migration tests it is possible to- make some deductions which will be of service in the consideration of the possible life history of this insect. It appears very doubtful whether the lice migrate to cotton from watermelon, from muskmelon, or from cucumber. Migration will take place from cowpea and okra at any time. Migration from squash and pumpkin may take place. Begonias may serve as a winter host for this species to infest the fields in the‘ spring. There is no migration to watermelon, from cotton, from okra, or from cowpea. Migration among the cucurbits is free at all times.. From squash and pumpkin migration may occur. To muskmelon there+ is no migration from cotton and okra, and it is doubtful from cowpea.. The migration from squash and pumpkin is not of common occurrence. To cucumber there is no migration from cotton or cowpea, but some from okra, from squash, and from pumpkin. To okra the lice will migrate from all the hosts with the possible exception of cucumber. To cowpea the lice will migrate from cotton, watermelon, okra, squash, and? pumpkin. Only the light form from muskmelon and cucumber will’ establish on cowpea. There is no migration from cowpea to squash, but from all the other hosts the lice will establish themselves. To pumpkin the lice will establish from all the hosts except okra. There is no mi-- gration to the gourd from cotton and okra, but the lice will establish from watermelon, cucumber, and pumpkin. There is a free migration between cotton and okra at all times, but iore restricted between cowpea and cotton. There is a. free migration between cotton and okra and the cucurbits. There is a possible mi- gration between cotton and squash, between cotton and pumpkin, and between these plants and the (iucurbits. 46 TEXAS AGRICULTURAL EXPERIMENT STATION. HIBEBNATION. From the field observations made at College Station it is evident that this plant louse feeds on cotton very late in the winter. In December young apterous lice were found in the fields, which fact would indicate that the insect can withstand rather 10w temperatures. However, the infestation is decidedly reduced after killing frosts in the fall. In the southern part of the State, where cotton is growing in the fields through- out the winter, this insect will readily pass that portion_of the year in the field. During the winter the periods of life history are merely lengthened. ALTERNATE HOST PLANTS. A review of the seasonal notes will show that there is a part of the year during which this insect is not found upon any cultivated host plant. In both years the lice were first observed in the field about May 24;, which is nearly as early as the plants are of sufficient size to attack. The general infestation in the field continues until the first killing frost, October 15 to 26, at College Station. A slight infestation has been observed until December 8. This louse has not been observed to col- onize on any plant o-ther than the cultivated plants as listed. ANNUAL LIFE HISTORY. From what has just been said it is evident that the life history of this insect in all sections of the State is still a perplexing problem. T-he louse usually appears in the field as soon as cotton is developing the second or third pair of leaves. If cucurbits are available at this date, they also are attacked, although in most sections these plants are not infested until a few weeks later than cotton. The migration tests show that the louse will go from cotton to cucurbits, or from them to cotton. The infestation o-n cotton increases during the month of June, and then decreases during July and August. The same is true of the infestation on okra. On the cucurbits the infestation increases with greater rapidity and continues until the plants are killed. The louse is present on cucurbits growing in this locality. During September and the first half of October the infestation gradually increases, but after the first killing frost the lice leave the cotton very rapidly. RELATION OF ANTS. The relation of aphids to ants has been recognized for many years. As early as 1883 J ones(14) called attention to the fact that three species of ants were commonly attending cotton lice. Only one of these species was identified by him as M yrmica malesm. In 1910 Marsh(15) records a very close relationship between this aphid and FOTNV/iCCI, cinereorufibar- bis Forel. Recently Horton(16) has given an account of his extended observations on the relation of the Argentine ant, I ridomyrmea: humilis Mayn, to this plant louse. In the present work, ants attending the lice were first observed in the insectary on March 9, 1916. At that time the host plants growing in the benches were heavily infested with lice. A careful examination THE CoTToNoR MELoN LoUsE. 47 showed that several colonies of ants were Well established in the soil; and apparently the ants were just beginning their scouting operations at this time, for they were observed on several of the host plants, al- though‘ lice Were not present on all. However, the ants were most numerous where the lice were most abundant, on cotton and on okra. 1 On March 23 an ant in its travel over a cotton plant Was observed detect an egg of a syrphid. Immediately the ant became excited almost instantly began tearing the egg, Which came loose from the eaf before the shell was broken. With its load, the ant started ‘down he stalk‘ to the ground and to its nest, Which was seven feet from the lant. After going about six inches from the plant the egg was laid own, apparently so the ant could. rest. During the journey to the nest any antswere passed, some of which stopped to inspect the load, but one made any attempt to relieve the first ant. .1 base of a heavily infested squash plant there Was a colony of ants. ,hese ants seemed to confine their travel to the plants in the imme- “ate vicinity of their nest. Four feet away was another nest, but the E ts from this nest never worked close to the other. Two adult lice Were observed crawling on the ground close to the base of a squash nt. Many ants passed these lice but with no more concern than to around them and on their way to the plant. When lice Were placed ‘w to the hole of the nest, the ants seemed concerned only with get- f4 around the lice and on with their errand. In the field the ants were found attending the lice as soon as they _re established on the p-lants May 24,-1916. Three species of ants re present at that time. - They Were determined by Dr. W. M. Wheeler Dorymyrmea: pyram-ic-zzs Reg. sub. sp. flcwus Mac Cook; Solenopsis mineia Fabr. sub. sp. myloni Mac Cook; Dorymyrmeé: pyramicus Vi; sub. sp. bmmrzeuvs Forel. When first observed the ants Were work- 1_ almost wholly on cotton. On this host the louse infestation was '= advanced, and the ants were observed to visit the nectaries on the er sides of the leaves. No ants were found on any of the cucurbit okra where the plants became heavily infested, the ants became i erous. hroughout the fall the ants were present whenever lice were found ‘cotton. A large cage was maintained at thisseason for the study he relation of ants to the lice. No ant nests were established within cage, but visits were made to the cage from nests fifteen feet dis- i The nests were generally in soil that had not been cultivated a. the season, between the cotton plants in the rows. Throughout period of observation no ant was seen to» care for a louse in any i Lice of all stages were seen on the ground at different times, when not on the plant they were quickly passed up by the ants. On ,m_ber 22, 1916, small colonies of lice were found by following the el of ants. The only attention given to the lice was to» obtain the y dew. At this season the few lice present in the fields were always , attended by the ants. h following spring many of the ant nests that had been observed l: fall were dug up carefully. This was done just before cotton ; By April 1 colonies of ants were quitenumerous in the benches. At i Vnts that were being grown for the host plants adjacent to the cotton. ' ~18 TEXAS AGRICULTURAL EXPERIMENT STATION. i as the eggs of predacious enemies are destroyed. The ants are not f was planted. In no instance Was it possible to- detect any plant lo in any stage being cared for in the ants’ nests‘. If From what has been observed concerning the relation of ants to i plant, it would appear that the ants are able to collect great quanti». of honey dew and that they may afford protection to the lice in so’ pendent upon the lice as they secure much food from the nectaries, the cotton. The lice are not dependent upon the ants as they becf_ established previously. i r i - NATURAL ENEMIES- This plant louse is subject to the attacks of several enemies. Fi notes show that the combined attacks of these enemies may result? almost. wiping out an infestation of lice. The value of these enemies hard to appreciate, for much of their ‘work is often unnoticed. a " PARASITES. .Ly.s/ipi1leZ.-ezs iflStd-CétLlj/‘GS Cress. 1 This parasite has been found in large numbers Wherever this louse was found. In fact, the parasite is known in literature as y melon louse parasite. It does, however, feed extensively upon ot common plant lice, some of which are closely associated with the co" or melon louse. The original description of this parasite Was given Bulletin 180 of this Experiment Station. r- Parasites were first observed in the field on May 25, 1916, which the next day after the-first lice were observed‘ on cotton. The num o-f parasites increased steadiy, and bv June 5 the lice present heavily parasitized. The following Week 95 per cent of the lice in cages Were parasitized. The adult parasites were very numerous all the cotton in the field. Soon it was hard to find an adult lo that was not parasitized. Bv June 15 most of the parasites i’ emerged from the lice. From this (late the numbers of lice Were gre ‘reduced. On June 2'7 all the mature lice in the cages were parasiti 1 From this time on the infestation on cotton in the field was very lig During thelast week in September a few p-arasites were again obse in the cotton field. During the cool weather of October the did not increase very much and finally disappeared from the field j November l. » PREDACIOUS ENEMIES. These enemies are of very considerable importance in the na i factors of control of this plant louse. These enemies are not so pered in their activity by climatic conditions as are the parasites. i predacious enemies are present every year and are present during; greater portion of the year than are parasites. Lady Beetles. The most important of the predacious enemies are the lady or coccinelids. In both the immature and the adult stages these r; THE COTTON on MELoN LoUsE. t 49 feed on plant lice. Seldom, however, do the beetles become abundant enough to exterminate the lice. i Three species of coccinelids have been commonly observed in the studies on this plant louse. In order of im- portance they are Megilla maoulata. DeG., Hippodamia. convergeious Guer, and Ooccinella munda. Say. Syrphid Flies. These enemies ofthe louse were commonly found in infested fields. The two species observed were Syvrpltus americanrus Wied., and Allo- grapia obliqua Say. These were present in about equal numbers. SUMMARY. The cotton or melon louse is found widely distributed over the world. It is common throughout the United Stateswhere any of its host plants are grown. In Texas this insect is a serious pest of cotton and the melons (cucurbits). There has been much confusion in the identity of this species as it is supposed to have a very long list of food plants, all of which were not verified in this study. ' In Texas the normal form of reproduction is asexual throughout the entire year. The alternate host plants in this State have not been de- termined. Fifty-one generations completed their life cycle in a period of exactly twelve months. The average reproduction period was 21.4 days and the average young produced was 84.4. The migration tests indicate that the lice do not migrate from cotton to the cucurbits or the reverse. Ants were found associated with the lice at all times, but no definite relation was established. The plant louse is reduced by natural factors of control. One species‘ of parasite, three species of ladybird beetles, and two species of Syrphid files were observed to prey on this louse. LITERATURE CITED. (1) 1854. Gloven-Townsend. Patent Office Report, pp. 60-62. First account of the species. (2) 1855. Glover, Townsend. Patent Office Report, p. 68. Re- prints first account. 1876. Glover, Townsend. Report Dept. of Agr. 1876, p. 26. Refers to two (2) and gives species name as gossypii. (4) 1878. Thomas, Cyrus. Ill. Lab. Nat. Hist. Bull. Vol. 2, p. 14. _ Lists the species as occurring in the‘ United States. (5) 1880. Ashmead, Wm. H. Orange Insects. Describes gossypii as S. citrifolii from orange. (6) 1882. Ashmead, Wm. H. Florida Dispatch, n. s. Vol. 1, p. 241. Describes gossypii as citrulli from melons. (7) 1882. Ashmead, Wm. H. Canadian Entomologist, XIV, p. 91. ' Describes citrifolii as in part gossypii. (8) 1883. Forbes, S. A. Twelfth Report of Oll., p. 83. Describes A gossypii as cucumeris from cucumber. (9) 1887. Oestland, O. W. Minn. Geol. & Nat. Hist. Sur. Bull. 4, l l p. 68. Lists species as occurring in the United States. 50 TEXAS AGRICULTURAL EXPERIMENT STATION. (10) 1895. Pergande, Theodore. Insect Life, VII, Vol. 5, p. 309. First general account of the insect. (11) 1908. Gillette, C. P. Jr. Eco. Ent. I, No. 3, p. 1'76. Dis- cusses closely allies species and gives distinguishing characteristics. (12) 1909. Essig, E. O. Pomona Jr. Ent. I, p. 4'7. Describes gossypii as citri. (13) 1911. Essig, E. O. Pomona Jr. Ent. III, No. 4, p. 590. De- tailed account with good description of forms. (14) 1883. Jones, R. W. Bur. Ent. Bull. I, p. 4'7. Records three species of ants attending the louse. (15) 1910. Marsh, H. O. Bur. Ent. Bull. 64, pt. IX. Discusses relation of a species of ant to the louse. (16) 1918. Horton, J. R. Dept. of Agri. Bull. 647. Records observa- tions o fthe relation of the Argentine ant to the louse. (17) 1918. Lochhead, W.) 10th Report Quebec Society Plants. Mentions species and gives host plants. BIBLIOGRAPHY . Ashmead, W. H. 1880. Orange Insects. Redescribed species as Siph- onophora citrifolii. Found to infest orange trees. Ashmead, W. H. 1882. Florida Dispatch, n. s. Vol. 1, p. 241. Briefly described as A. citrulli. Very destructive to watermelons in- Florida and Georgia. - Ashmead, W. H. 1882. Aphididae of Florida, with description of new species. Canadian Entomologist, Vol. XIV, p. 91. In the Aphid- idae of Florida, citrifolii is again described; also another species now known as M yzus persiciae. " Ashmead, W. H. 1895. Insect Life, Vol. VII, No. 4, p. 323. Records occurrence in Mississippi and gives enemies. Ballou, H. A. 1903. West Indian Bull. 4 (’03). Economic and bio- I logical notes. Bogue. 1896. Melon louse (Aphis cucumeris Forbes). Okla. Sta. Bull. 20, p. 22. Injury described and remedies given. Britten, W. E. 1908. Eighth Report of State Entomologist, 1908. Records occurrence of species. - . Britton, W. E., and Clinton, G. P. 1915. Spray Calendar. Conn. Bull. 182, p. 15. Mentions species. Bruner, L. 1894. Report on Injurious Insects in Nebraska and Ad- joining Districts. U. S. Dept. Agr., Div. of Ent. Bull. 32, p. 59. Notes on cucumber plant louse (Aphis cucumefis). _ Bruner, L. 1907. Melon Aphis. Reports of State Entomologist and Botanist Neb. Records occurrence. Chittenden, F. H. 1898. Some Miscellaneous Results of the Work of the Division of Entomology, Div. of Dnt. Bull. 10 n. s., p. 62. Mentioned as feeding on asparagus. Chittenden, F. H. 1903. Principal Insect Enemies of the Sugar Beet. Bur. of Ent. Bull. 43, p. 58. Brief notes. Chittenden, F. H. 1906. The Melon Aphis. Bur. of Ent. Cir. 80. Complete account. ‘ THE CoTToN OR MELON LoUsE. 51 Churchill, O. O., and Wright, A. H. 1912. Cotton and Cotton Cul- ture. Okla. Sta. Bull. 98, p. 1.5. Notes and remedies are given. Conradi, A. F. 1907. The Melon Louse. Gulf Coast Mag, 3 (’07), No. 1., pp. 47-52, Fig‘. 6. Fumigation with nicotine, and enemies are discussed.“ i Davis, J. J. 1.910. A List of the Aphididae of Ill. with notes on some of the species. Jr. Eco. Ent, Vol. III, No. 6, p. 485. Found in melon fields and in greenhouses. Essig, E. C. 1.910. Aphididae of Southern California. Pomona, Cal. Jr. Ent., Vol. II, No. 2, p. 223. Describes the viviparous forms and gives host plants. , Essig, E. C. 1911. Natural Enemies of the Citrus Plant Lice. Po- mona, Cal. Jr. Ent. 3 (1911), No. 4, pp. 604-616, Fig. 10. ' Lists enemies of A. g0ssypii. Essig, E. O. .1915. Injurious and Beneficial Insects of California, p. 89. Brief discussion. Essig, E. O. 191.7. Aphididae of California. University Publication, Vol. 1, No. 7, p. 338. Lists species on new host plants. Pelt, E. P. 1.899. Country Gentleman 64, p. 128. Mentions species. Forbes, S. A. 1883. 12th Report Noxious and Beneficial Insects of Ill., pp. 83-91. Describes species as A. cucu-merts. Forbes, S. A. 1900. The Economic Entomology of the Sugar Beet. Ill. Bull. 60, p. 429. Gives host plants, description and habits. Pullaway, D. T. 1909. Insects Injurious to Cotton. (Hawaii Bull. 18, 1.909.) Life history, habits, and remedies are given. "ullaway, D. T. 1911. Entomological Notes. (Guam Sta. Repts. 1911, pp. 26-35, pl. 1.) Insects of economic importance. Melon Aphis mentioned. lullaway, D. T. 1911. Report of the Entomologist. (Hawaii Sta. Rpt. 1.911, pp. 17-24, Fig. 4.) A plant lo-use attacking legumes thought to be Aphis gttsrsiz/pii. l-ahan, A. B. 1907. G~reenhouse Pests of Maryland. Md. Bull. 119, 1907, p. 18. Mentions melon louse. larcia, F. 1908. Injurious Insects. N. M. Bull. 68,1908, p. 19. Injury’, methods of attack, and remedies are discussed. ‘rarman, H. 1901. Enemies of Cucumbers and Related Plants. Ky. Sta. Bull. 91, pp. 3-4 8, Fig. 14. Food plants, life history, enemies, and remedies. Mentions fumigators for tobacco extracts. laylord. 1842. Trans. N. Y. A.gr. Soc, No. 3, p. 127. Mentions melon louse. illette, C. P. 1906. Report of the Entomologist. Colo. Sta. Rpt. 1906, p. 142. Melon louse present in several localities. -illette, C. P. 1908. Aplvis glossy/pit Glov. and its Allies. Jr. Eco. En-t., Vol. 1., No. 3, p. 179. Discusses distinguishing features of closely allied species and food plants of each. -illette, C. P. 1910. Plant Louse Notes,—~Family Aphididae. Jr. Eco. Ent., Vol. III, No. 5, p. 404. Miscellaneous- collections in the U. S. lover, Townsend. 1854. Pat. Office Bpt. 1854, p. 62. Original de- scription of species. _ lover, Townsend. 1855. Pat. Office Rpt. 1855, p. 68. Mentions original description. 52 TEXAS AGRICULTURAL EXPERIMENT STATION. Glover, Townsend. 1866. Monthly Rpt. Dept. Agr., June, 1866. Notes of previous record. A Glover, Townsend. 1876. Rpt. Dept. of Agr. 1876, p. 36. Refers w Patent Office Report 1855. - ‘A Griffin, H. 1901. Insects Injurious to Cantaloupes. ColoQBullJ 62, 1901." Notes and remedies suggested. _ Howard, L. O. 1893. Amer. Gard. 14, p. 209. Mentions species. Howard, L. O. 1897. Insects Attacking‘ the Cotton Plant. lilarmers’? Bull. 4.7, p. Lists this species as injurious to young plants. " Hunter, W. D. 1901. The Aphididae of North America. Ia. Exp. Sta. Bull. 60, p. 96. Distribution, host plants, and synonyms. Johnson, W. G. 1896. Entomological Notes from Md. Bur. of Ent. Bull. 6 n. s., p. 65. Injury discussed and spray recommended. Johnson, W. G. 1897. ' Some Common lnjurious Plant Lice with Sug" gestions for their Control. Md. Bull. 48, pp. 91-97. Apterou forms said to be carried by ants. Food plants, p-reventives, an remedies are given. ‘ Johnson, W. G. 1898. Insects Prevalent in Maryland in 1896-7. H T; Bull. 57, 1898. Injurious pest. _ ‘f Johnson, W. G. 1899. Miscellaneous Entomological Notes. Bur. 0’ Ent. Bull. 20 n. s., p. 65. Ruined many acres of melons. Johnson, W. G. 1900. Notes on Insects of Economic Importance 1900. Bur. of Ent. Bull. 26, p. 82. Damage and remedies a =.» iven. Litngr, J. A. 1888. Country Gentleman 53, p. 725. Mentions species? Litner, J. A.‘ 1889. Injurious and Other Insects. N. Y. Entom, logical Bull. 5, pp. 306 and 326. _Mentions species-life histo 1 and enemies given. . Lochhead, W. 1918. 10th Report Quebec Society Plants, p. 85. Men tions species—-host plants given. ; Lounsbury, C. P. 1908.“ Melon Aphis. (Agr. Jr. Cape Good Hop 33, 1908, No. 1'1, pp. 491-496, Fig. 2.) Damage and enemies a iven. - ~ - Loungsbuijv, C. P. 1908. Melon Aphis. (Rpt. Gov. Ent. Cape Go " Hope, 1908, pp. 55-70.), Mentions species. - i McCarthy, G. 1891. Insects Injurious to Cotton. N. C. Bull. 1891, p. 13. Mentions species. . i; Merrill, A. W. 1914. Cotton Pests of the Year. Ariz. Com. of A J and Hort. Ann. Rpt. 6, pp. 9-47, Fig. 16. Cotton Aphis most d structive cotton pest of the year. ‘ . Oestland, O. W. 1887. Synopsis of the Aphididae of Minn. 7- and Nat. Hist. Sur. of Minn., Bull. 4, p. 68. Not yet in M1 a‘, sota. Also lists A. cizcilamieris Forbes. ‘ Osborn, II, and Mally, C. W. 1.894. Observations on Insect,—sea_ oi’ 1894. Iowa Sta. Bull. 27, pp. 135-149. Notes on melon lo Parrott, P. J. 1907. Investigations of the Department of Entomolo N.-Y. State Rpt. 1907, pt. 3, 'pp. 238-266. Aphis gossypii -._ tioned. a Patch, Edith M. 1912. Aphid Pests of Maine. Me. Exp. Sta. B‘ 202, p. 207. Lists species in food catalogue. THE COTTON or: 1112.101: LOUSE. 53 Patch, Edith M. 1913. Wooly Aphids of the Elm. Me. Exp. Sta. Bull. 220, pp. 289-292. Food Plant Catalogue of the Aphididae of the World. Patch, Edith M. 1918. ‘Eastern Aphids. Me. Bull. 2'70. Lists species in host index. Pettit, B. H. 1905. Insects of the Garden. Mich. Bull. 233, 1905, p. 29. Notes and remedies are given. Pergande, Theo. 1895. The Cotton or Melon Plant Louse. Insect Life, Vol. 7, pt. 4, pp. 309-315. Complete account. Quaintance, A. L. 1896. Insect Enemies of Truck and Garden Crops. Fla. Bull. 34, p. 296. General account. Quaintance, A. L. 1899. Ga. Bull. 45, 1899, p. 26, Fig. 1. General account. Riley and Howard, 1890. Extracts from Correspondence. Insect Life, Vol. I11, No. 2, p. 71. Ants attracted by Aphids. Riley, C. V. 1893. Injurious Insects of Maryland. Md. Sta. Bull. 23, pp. 67-94. General account. Ross, W. A. 1918. (Agr. Gaz. Can., Vol. 4, p. 344.) Mentions feed- ing the melon louse to Coccinelids. Sanborn, C. E. 1904. Kansas Aphididae. Kan. Univ. Sci. Bull., Vol. III, No. 1, p. 56. Technical account. Sanborn, C. E. 1906. Alelon Aphis and Other Related Insects. Tex. Sta. Bull. 89, p. 52. Fumigation a.nd encouragement of enemies of species. Sanborn, C. E. 191]. The Cotton or Melon Aphis. Okla. Sta. Bull. 98, pp. 3-20, Fig. 4. General account. Sanborn, C. E. 1912. Garden and Truck Crop Pests. Okla. Bull. 100, p. 25. Brief account. Sanderson, E. W. 1905. Miscellaneous Cotton Pests in Texas. Farm- ers’ Bull. 223, p. 6. Notes. Sanderson, E. W. 1906. Miscellaneous Cotton Insects of Texas. Bur. of Ent. Bull. 5'7, p. 26. Mentions species. Sirrine, F. A. and Lowe, V. H. 1894. Some Insects Injurious to Squash, Melon, and Cucumber Vines. N. Y. Sta. Bull. 7'5, p. 420. Description, life history, and remedy for A. czacuvneris. Smith, H. S. 1906-07. Aphids injurious in Nebraska. Ann. Rpt. Neb. Bd. Agr. 1906. Melon Aphis injurious to pickle growing. Smith, H. S. 1908. Ofiice State Entomologist Cir. 4. Brief account of life history, and remedies are given. Smith, J. B. 1890. Plant Lice and How to Deal with Them. N. J. Sta. Bull. No. 72, October 4, 1890, p. 27. N. J. Sta. Rpt. 1890, p. 484. General account. Smith, J. B. 1892. N. J. Bpt. 1892, p. 490. Life history and rem- edies are given. _ Smith, J. B. 1893. Insects Injurious to Cucurbits. N. J. Bull. 94, p. 19. Life history and remedies are given. Smith, J. B. 1894. Notes of the Year in New Jersey. Insect Life, Vol. 7, No. 2, p. 195. Brief notes. Smith, J. B. 1894. Report of the Entomologist. N. J. Rpt. 1894, p. 438. Mentions occurrence of species. Smith, J. B. 1895. N. J. Rpt. 1895, p. 478. Life history and rem- edies are given. 54 TEXAS AGRICULTURAL EXPERIMENT STATION. Smith, J. B. 1895. Report of the Entomologist. N. J. Sta. Rpt. 1895, part II, p. 388. Very injurious. ‘Smith, J. B. 1896. Report of the Entomologist. N. J. Sta. Rpt. 1896, p. 433. Causes much loss. Smith, J. B. 1897. The Harlequin Cabbage Bug and the Melon Plant Louse. N. J. Sta. Bull. 1.21, p. 14. Popular account. Smith, R. I. 1910. Insect Enemies of Cantaloupes, Cucumbers, and Related Plants. N. C. Sta. Bull. 205, p. 3. Life history is given. tedrnan, J. M. 1893. Aphids or Lice on Cotton. Ala. College Sta. Bull. 45. Life history and remedies are given. Stewart, F. C. 1897. Insects Affecting Cucumbers. N. Y. Sta. Bull. 119, p. 156. Brief notes are given. Surface, H. A. 1.902. Insects Injurious to Cucurbitaceous Plants. Pa. Dept. Agr. Bull. 96, p. 30. Melon louse is mentioned. Swenk, M. H. 1910. Spraying for the Melon Aphis. Neb. Sta. Rpt. 1910, p. 35. Summary of life history, habits, injury. Reviews spraying experiments against the melon louse. Swenk, M. H. 1911. Neb. Exp. Sta. Press Bull. 341. Methods of com- bating the louse are given. Symons, T. B. 191.13. Proceedings 16th meeting A. A. E. E. Bur. Ent. Bull. 4:6, p. 98. Mentions species. Tavares, J. S. 1914. A catalogue of Portuguese Aphids (Broteria Ser. Zool., Vol. 12 (19111), No. 3, pp. 177-193.) Mentions species. Thomas, Cyrus. 1878. Ill. Lab. Nat. Hist. Bull. No. 2, p. 111. Records species as having been described in U. S. from cotton. Thornber, J. J. 1902. Ariz. Bpt. for 1902, p. 2641. Brief notes on “nianteca.” disease, considered due- to the melon louse. Walker, E.‘ 1901. Insects Injurious to Muskmelons. Ark. Bull. 69, 1901, p. 81. Brief notes and remedies are given. Washburn, F. L. 1.901. Injurious Insects of 1904. Minn. Bull. 88, p. 80. Brief notes and remedies are discussed. Wilcox, E. M. 1900. Notes on Troublesome Insects and Plant Dis- eases. Okla. Ppt. 1900-1902, p. 112. Brief notes. . ll-iilliams, T. A. 1911. The Aphidirlae of Nebraska. Univ. of Neb. Studies, Vol. XI, pt. 3, p. 13. Records species. Wilson, H. I. and Vickery, B. A. 1918. List of Aphididae. Wis. Acad. of Sci, Vol. XIX. Lists food plants. Woodwortli, C. W. 1915. Aphids on Grain and Cantaloupes. Cal. Sta. Cir. 125‘. I’opular account.