Fourth Report of the United States Entomological Commission

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Fourth Report of the United States Entomological Commission
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United States Entomological Commission
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U.S. G.P.O. ( Washington )

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HUME LIBRARY
INSTITUTE OF FOOD AND AGRICULTURAL SCIENCES

UNIVERSITY OF FLORIDA
Gainesville







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U. S. DEPARTMENT OF AGRICULTURE.




IFO URTIH R REPORT

OF THE


UNITED STATES



ENTOMOLOGICAL COMMISSION,

BEING A REVISED EDITION OF BULLETIN NO. 3,
AND THE FINAL REPORT

ON TIlE


COTTON WOR M,

TOGETEIER WITH A CHAPTER ON THE


BOLL WORM.



BY
CHARLES V. RILEY, Ph. D.





WITH MAPS AND ILLUSTRATIONS.






WASHINGTON:
GOVERNMENT PRINTING OFFICE.
1 885.





























CONCURRENT RESOLUTION authorizing the printing of thirty thousand copies of the second
edition of Bulletin No. 3, or fourth report of the United States Entomological Commission.
LN THE HOUSE OF REPRESENTATIVES,
January 27, 1881.
The following resolution, originating in the House of Representatives, was this day concurred in by the Senate:
Resolved by the House of Representatives of the United States of America, (the Senateconcurring,) That there be printed at the Government Printing Office 30,000 copies of the second revised edition, with necessary illustrations, of Bulletin No. 3, of the United States Entomological Commission, being a report on the Cotton and Boll Worms, with means of counteracting their ravages; 10,000 copies thereof for the use of the Senate; 18,180 for the use of the House, and 1,820 for the Interior Department.
Attest:
GEO. M. ADAMS,
Clerk.

















TABLE OF CONTENTS.


Page.
LETTER OF SUBtIMITTAL ...... ............................................... xvii
PREFACE x................................................................... XiX
INTRODUCTION xx.............................................................. X iii

CHAPTER I.

CLASSIFICATION AND NOMENCLATURE. DESTRUCTIVENESS ................... 1
Popular and scientific names, 1-most desirable popular name, 1-different
technical names, 1-history of these names, 1-the name A1letla xgylina the correct one, 1-synonomyN of the insect, 2-classificatory position, 2-importance of the family Noctuidm,. 2-destructivcness of the worm, 2-causes which increase this destructiveness, 2-regions where losses are greatest, 2-and least, 3-tabular statement of losses, 3-previous
statements, 3-statement of loss in l1, 4.

CHAPTER II.

CHARACTERS, HABITS, AND NATURAL HISTORY ................................ 5
Distinct states of growth, 5-the worm must hatch from an egg, 5-description of egg, 5-where the egg is laid, 5-nunmiber of eggs to a leaf, 6time elapsing before hatching, 6-unhatched eggs perish when frozen, 6insects' and other eggs mistaken for eggs of Aletia, 6-chbaracters of worm, 6-description of newly-hatched wori, 6-number of molts, 7-different colors of worm, 7-habits of worm at different stages, 7-jumping habit, 7-only known to feed on cotton and one another, 8-odor of the worim, 8-migrations of worm, 8-method of pupation, 8-formniation of cocoon, 8-the worm never burrows in the ground, $-distinctive characters of the chrysalis, 9-duration of chrysalis state, 9-distiuctive characters of the moth, 9-sexual diterences in the moths, 9-different habits of the moths at night and by day, 10-their strong flight, 10-their position at rest, 10-how soon the female begins to lay, 10-her prolificacy, 10-food of the moth, 10-it injures fruits, 11-structure of the tongue, 11mention of other Noctuidze which injure fruits, 11-time elapsing from one generation to another, 11-this will average about one month, 12time of year when the first worms appear, 12-former opinions erroneous, 12-dates of earliest appearance variable, 12-worms of all sizes found in Florida and Southern Georgia in the latter part of March, 12-first worms always few ail scattered, 12-they multiply and spread irregularly, 12-their progress governed by the season and latitude, 13-the third generation often called the first, 1'3-number of annual generations, 13-there are at least seven in Southern Texas, 13-gradual progress and succession of broods, 14-the second generation exceptionally very injurious, 14-why not usually so, 14-extent of migratory flights of the moths, 15-probable existence of northern food-plants, 15-causes and seons of migration, 15-behavior of migrating moths, 15-the question 1[5"~EB lm






IV TABLE OF CONTENTS.


CHARACTERS, HABITS, AND NATURAL HISTORY-Continued. Page.
of hibernation, 15-different former opinions and beliefs concerning hibernation, 16-discussion of these opinions, 16-the chrysalides are killed by a temperature below 220 F., 16-paiasited chrysalides can bear greater cold, 16--fallacy of the belief- that the chrysalis winters underground, 16-ease with which erroneous conclusions can be drawn from mistaken identity, 17-the chrysalis of Aspila virescens mistaken for that of the Aletia, 17-chrysalides of other cotton larve found underground in abundance, 17-the chrysalis of Aletia killed by burial, 17-ability of the moth to survive the winter, 18-unreliability of most testimony as to the hibernatin of the moth, 18-other moths easily mistaken for it, 18Hypena scabralis, 18-Phoberia atomaris, 19-Leucania unipuncta, 19-absence of testimony to the survival of the moths beyond March, 19-theory of annual introduction of the species from some southern foreign count ry, 19-statement and discussion of Grote's arguments and of others in support of this theory, 20-arguments in favor of the hibernation of the moth, 21-both immigration and hibernation may occur, 21-summary of the evidence, 22-Aletia hibernates only as a moth and only in the extreme south, especially in Texas, 22.

CHAPTER III.

PAST HISTORY OF THE COTTON WORM IN THE UNITED STATES .......--------------...... 23
From 1793 to 1825, 23-from 1826 to 1846, 24-from 1847 to 1866, 25-from
1867 to 1869, 26-from 1869 to 1872, 27-in 1872 and 1873, 28-in 1873 and 1874, 29--in 1875 and 1876, 30-in 1877 and 1878, 31--in 1879 and 1880, 32in 1880 and 1881, 33-history of remedies, 34-hand-picking and poultry, 34-fires, 35-other remedies, 35-36-arsenic, 36-Paris green, 36-38planting jute, 38-machinery, 38-London purple, 38-pyrethrum, 38.

CHAPTER IV.

THE COTTON WORM IN OTHER COUNTRIES ..................... ........... 39
Geographical distribution of Aletia xylina, 39-other insects injurious to
cotton in the Eastern Hemisphere, 39-occurrence of Aletia xylina on the Pacific coast of Mexico, 39-40-on the Gulf coast of Mexico, 40-41-in Yucatan, 41-in the West Indies, 42-in the northern countries of. South
America, 42-43-in Brazil, 43-44.

CHAPTER V.

ON THE ANATOMY OF ALETIA. BY EDWARD BURGESS AND C. S. MINOT...... 45
Circumstances under which this chapter was prepared, 45-external anatomny of larva, 45-true legs, 45-prolegs, 46-colored markings, 46-stigmata, 46-internal anatomy of larva, 47-ead, 47-ganglia, 47-diges tive canal, 47-malpighian vessels, 47-salivary glands, 47-dorsal vessel, 47-stomach, 48-external anatomy of imago, 48-method of preparing the exoskeleton for examination, 48-head and appendages, 48-prothorax, 48-49-mesothorax, 49-mietathorax, 49-50-supposed organ of hearing, 50-abdomen, 50-51-spiracles, 51-legs, 51-scales, 51-52---scalepores, 52-proboscis, 52-spines, 53-internal anatomy of imago, 53-digestive canal, 53-pharynlx, 53-54-salivary glands, 54--esophagus, 54food reservoir, 54-55-stomach, 55-malpighian vessels, 55-intestines, 55-aorta, 55,-nervous system, 55-ganglia, 55-terminal body segments and organs of replroduct ion, 56-brush-sac, 56-male organs of reprodueotion, 5 --testes, 57-vasa deferentia, 57-penis, 57-female organs of reprod cti ion, 57-ovaries, 57-sebaceous glands, 57-vagina, 58-copulatory
pouch, 58--terminal abdominal segments of the female, 58.






TABLE OF CONTENTS. V

CHAPTER VI.
Page.
TEz CoTTox BELT. BY PROF. E. A. SI---................................. 59
A. General feature of the cotton States ......--..--...............-..........-- 59
Region included in the cotton belt, 59-clitmate, 59-winds, 59-rainfall, 59-61-temperature, 61-62-geological sketch, 62-63-topography, 6364-soils, 64-45--agricultural subdivisions, 65-regions of forest growth,
66-67.

B. D option of the agricultural subdiisions .............................. 67
The alluvial region, 67-8-the lower prairie region, 63--69-the long-leaf pine region, 69-71-the oak uplands region, 72-73-the upper prairie region, 73- 7--the red and brown loam region, 75-77-the sandy and siliceous lands of the older formations, 77-79-the gneissic region, 79-80.

CHAPTER VII.

TERRESTRIAL AND METEOROLOGICAL INFLUENCES AFFECTING THE WORM..... 81
Condition of soil and plant connected with the appearance of the first
worms, 81-the earliest worms are confined to the '"low lands," 81--and to luxuriant plants, 82-and to the vicinity of winter shelters, 2-and to the same localities, 82-influence of wet weather on the development of the worms, 63-severe rains with gales destroy both worms and crop, 83-late cold rains do the same, 84-frequent summer rains favor the development of the worms, 84-hot, dry weather destructive to them, 84artificial drought produces the sme effect, -4-indirect influences of wet weather in favoring the development of the worms, -imnmunity of the worms from their enemies in wet weather, ."Qlrowuing of ants by heavy showers, 85-wet weather prevents poisoning and working the cotton, 5letter from J. W. Du Bose on the influence of winds on Aletia, 85-86.

CHAPTER VIlI.
JNATURAL ENEM1ES...... ----..- ---- ----.. . .-- -------- 87
General remarks, 87-importance lessened by the use of arsenical poisons,
87-vertebrate enemies, -7-quadrupeds, 87-birds, 87-English sparrow, 88-toads and lizards, 89-invertebrates, 9-spiders, 89-ants,90species of ants destroying Aletia, I0-- lubbard's observations on ants, 92-the leaf-cutting ant, 94-wasps, 94-Coloptra,4-Coloptra 95-tiger-beetles, 9 -ground-beetles, 95-lady-hirds, 93-soldier-beetles, 96-Heteroptera, 97 -list of species, 97-Dipteia, 99-Orthoptera, 99-Neuroptera, 100-Lepidoptera, 100-parasites, 101-list of species, 101-the Trichogranuna eggparasite, 102-the cotton-worm Microgaster, 104-Comstock's Euplectrus, 105-Elachitu. euplectri, a secondary parasite, 106- the common flesh-fly, 107-Cyrtoeura stabulans, 108-is it parasitic ? 10S- tachina-flies, 109their habits, 109-the watchful Pimpla, Ill-the Ring-legged Pimipla, 113 -Cryptu8 nunciuN, 113-the Ovate Chalcis, 114-the Devouring Tetrastichus, 115- species that are easily mistaken for parasites of Aletia, 115Hexaplasta zgizag, 115-Phora aleli(, 116.

CHAPTER IX.
PREVENTIVE MEASURES--.......................----- -- ........................ 120
Mode of cultivation, 120-improving cotton seed, 120-forcing the young plants, 120-transplanting from hot-heds, 120-objections, 121-frequent cultivation, 121-topping the cotton, 121-fertilizers, 121-sulphuric acid on seeds, 121-late planting, 121-" worm-proof cotton," 121-diversitied agriculture, 122-rotation of crops, 122-jute as a protection, 122-






VI TABLE OF CONTENTS.

Page.
PREVENTIVE MEASURES-Continued.
other supposed protective plants, 123-protection of Natural Enemies, 123-immunity of cotton under trees, 124-preventing oviposition of the moth, 124-futility of decoctions for this purpose, 125-road dust, 125-early application of direct remedies, 126-concerted action, 126early poisoning and hand-picking, 126-cotton-worm warnings, 127destroying chrysalides accidentally carried into gin-houses, 127-false
theories, 127-burning the stalks, 127-winter plowing, 17-salt, 127.

CHAPTER X.

REMEDIES; MEANS OF COPING WITH THE INSECT; SUBSTANCES USED FOR ITS
DESTRUCTION ..---......------------------------......................-----------------------.........-------............... 128
Destruction of the eggs, chrysalides, and moths, 128-destruction of the
eggs impracticable, 128-little chance for successful destruction of the chrysalides, 128-destruction of the moth, 129-lights and fires for attracting the moths, 129-indifferent success with lamps used at Columbus, Tex., 130-importance of using lamps early in the season, 130-apparent success with lamps near Hearne, Tex., 131-great attractiveness of the electric light, 131-movable lights, 131-poisoned sweets and fluids, 131-fondness of the moths for ripe fruit, 132-killing moths by poisoned fruit, 132-method of using poisoned liquids, 132-no results from using poisoned baits late in summer, 133-poisoning the glands of the plant, 133-cotton-leaf essence and its attraction to the moth, 134-hand-picking, 135-mechanical means of killing the worms, 136-shaking off the worms, 136-poisoning the worms, 136-progress in the use of insecticides, 137-classification of insecticides, 137-importance of preparing materials in advance, 138-arsenical compounds, 138-safety in their use, 138--difficulty in determining minimum quantities, 139overdoses of poisons, 139-general rules in dry applications, 140-mixing devices, 141-ingredients, 141-wet application, 142-principles to be followed and ingredients to be used, 142-comparison of dry and wet applications, 142-Paris green, 143-historical data, 143-liquid application, 143-dry applicatiori, 144-minimum quantities, 144-patents on Parisgreen combinations, 146-arsenic, 147-commercial arsenic, 14-7-arseniate of soda, 147-Fowlers's solution, 148-Johnson's dead shot, 148-Texas cotton-worm destroyer, 149-London purple, 149-manufacture and analysis, 149-history of its use, 150-experience in Alabama in 1880, 150-advantages and disadvantages, 151-dry application, 151-wet application 152-other mineral substances, 153-salt and saltpeter, 153-sulphur, 154red lead, 154-road dust, 154-oils and allied substances, 155-kerosene, 155--former methods of apphcation,' 155-invention and perfection of emulsions, 156-method of preparing emulsions, 157-formula for perfected emulsion, 158--experiments with imperfect emulsion in 1880, 158experiments with perfected emulsions, 160-oil of creosote, 162-oil of tar, 162-gas-tar water, 162--carbolic acid, 163-cotton-seed oil, 163vegetable insecticides, 164-pyrethrum, 164-history, 164-mode of cultivation, 165-success in cultivating the plant in America, 166-preparation of the powder, 167-its use as an insecticide, 168-advantages and disadvantages, 168-active principle in pyrethrum, 169-its effects on cottonworms, 169-imported v8. Californian powder, 170-dry application, 170minimum quantities of dry powder, 171-dry powder mixed with flour and other ingredients, 172-application in fumes, 174-alcoholic extract, 174-experiments with extract obtained by distillation, 174-experience with extract obtained by repercolation, 176-use of the powder in simple






TABLE OF CONTENTS. VII

Page.
REMEDIES; MEAS OF COPING WITH THE INSECT, ETC.-Continued.
water solution, 177-tea or decoction of pyrethrum, 178-effect of pyrethrum upon other insects, 179-prospects for the use of pyrethrum for the cotton-worm, 180-ox-eye daisy powder and its uselessness as an insecticide, 180-extracts and decoctions from various plants, 181-difficulties in the way of discovering new vegetable insecticides, 182-mode of preparing the extracts and diffusion, 183-list of the plants experimented with, 184-effect of alcohol upon the worms, 187-yeast ferment and fungus infection, 188-Dr. Hagen's recommendations of the use of yeast as an insecticide, 188-objections to Dr. Hagen's plan, 189-negative results
obtained by the Commission, 190.

CHAPTER XI.

MACHINERY AND DEVICES FOR THE DESTRUCTION OF THE WORM. BY PROF. W.
S. BARNARD, PH. D---........ ........................................... 191
I. SPRAY NOZZLES, classification, preferred kinds, 191-Many-punctured
,ozzles, 191-6-preferred construction, 191-3-straining and cleaning vs.
clogging, 192-Eddy-roses, their operation, construction, and leading importance, 192-3-Plug-roses, action and construction unsatisfactory, 1934-Johnson's, Melcher's, Dawson's, Foster's, 193-Lynch's, 194-Colliding jets, gas-jets, superiority, Daughtrey's, Weber's, Prouty's, 194-T-roses, 194-Yeager's, Warner's, improvements, 19-Divided rose-heads, clutchhead of Mast, Foos & Co., Foss, Fox's, Barrows', Vose's, 195-Peripheralroses [divided], Melcher's, Yeagers, Ruhmann's, 196-Rose-combinations of Barry, Prentice, &c, 196-Slot nozzles, 196-205-operation, 196-preferred construction, 196-201--disadvantages, improvements made, 197201-Eddy-chambered, 197-9-lip construction, 198-9-inside cleaner, 199 -Simple slot-nozzles, Fowler's, Mallory's, Iske's, 201-202-Plug slot-nozzles, Allen's, Ruhmann's, Johnson's, The Niagara," Pinter's, 202-Removable slots of Long, Vestal, and Merigot, 203-Jawed slots, The Boss Nozzle," Raymond's and Perkin's, Smith's, Moffet's, 203-Williams', Iubmann's, Pinter's, 204-Stanton's, 205-ide slots, Schier's, Melcher's, 205 -Defletor nozzle, 206-211-definition, use, applicability, relative merits, 206-rip-waste, clogging, 206-simple constructions made, 206-8--conformations for narrow, wide and even sprays, 20G-7,-removable deflectors, 207-Holing', Douglas', Nickerson's, Hayden's, 208-ayden's, Killam's, Lewis', Schier's, Barrett's, 209-Rubmann's, Binkley's, Schier's compound, 210 -Schier's and Polansky's, 211-Centrifugal nozzles, 211-221-operation, kinds, choice, 211-the new and most perfect sprayers, 212-Eddy-chambered, 212-219-conformation and operation, 212--clogging, cleaning, construction principles, 213-forms described, 214-Whistle-jets, 215-216for blast-atomizers 216-Eddy-jet proper, 216-219-involute form, coneform, 216-convex and concave forms, 217-direct discharge, proximal diagonal discharge, 217-distal diagonal discharge, 218-centrifugal nosepieces, double-cone or double-chambered form, and chambered plug form, 218-direct sprav and solid jet, 219-Fifular spray nozzles, hose-pipes, 219-with rotary segment, Hotz's, Clifford's, Gielow's, Johnson's, Hoyer's, Clarke's, 220-with cross-plug, McGaffey's, Johnson's, Gray's, Gielow's, Hosford's, 221-Spray-wheels, 221.-Il. CENTRIFUGAL THROWERS, 221-226 -their character and operation. 221-Rotated orifices, Pronged reels, Brush poison-throwers, 222-brush fibers, 222-3-rotary polishing brushes, improved construction, fiber-strength, spring and density, 223-feeding the brushes with liquid, 223-5-with powder, 224-a simple brush thrower of powder, 224-5-advantages over sifters, velocity of rotation,






VIII TABLE OF CONTENTS.


MACHINERY AND DEVICES FOR THE DESTRUCTION OF THE WORM-Continued. Page.
225-Wisewell's, 2"25-6-whisps and brooms, rotated recesses, 226--III.
BLOWERS OF POISON, 226-252-Itotary Blowers, 226-235-kinds and success of, 2"26-7-For blowing powder, 227-232-hoppers and adjustable feeders, 227-8-blower encasements and blast-pipes, 228-9-blast forks and deflectors, 229-improved light rotary blowers, 229-230-hauled blowers, compound rotary blower, A-frame and legged swivel wheels, 230-rotary velocity, 231-Hurd's rotary powder blower, 231-2.-For blowing liquids, 232-5-improved feeders of liquid to rotary blowers, 232-3-drip-catcher, forked blast spray, 233-Darnell's rotary liquid-blower, 233-4-Hurd's ditto, and Perl's rotary fume-blower, 234-Force-blast Rotary BlowersOscillating blowers, 235-251, bellows power, construction, durability, improvements, 235-6-For blowing powders, 236-243-hermetic powder-box, 236-feeders of powder to blasts, 236-7-pipes, forks, and nozzles for these powder blasts, 237-8-hauled compound bellows powderer, to wagon, with motor, &c., 238-cultivator bellows-blower, 238-9-knapsack and horse-back bellows powderers, 239-improved small hand bellows powderers, 239-241-with forks, 241-Allen's'powderer, 241-common powder bellows, Woodason's, Hendley's improved, 242-Stelle's, &c., 243-For blowing fluids, 243-9-importance, resuction, feeding by blast-suction, blastpressure, gravitation, gauges, 243-4-blast spray conductors and nozzles, reverberatory, 244-whistle-jets and agitation chambers, 245-common blast atomizers, 245-improved automatic-feeding blast sprayers, 246-9reatomizing, reverberatory nozzles, 247-nether blast sprays, directing pipes and nozzles, 248-compound combinations, 249-Peck's blast sprayer, and Wallace's, 249-Reciprocating or pistoned Blowers, 249-251improved air-pump apparatus, 249-950-air-pumps of Humphryville, Rumsey, &c., 251- Generator Blowers, 251-2-Steinmann's vaporizer, 251.

CHAPTER XII.

MACHINERY & DEVICES FOR THE DESTRUCTION OF THE WORM-continued... 253
IV. PNEUMATIC COMPRESSION SQUIRTERS, 253-261-kinds, advantages,
available fire-extinguishers, 253-4-carbonic anhydride, apparatus, practicability, 255-danger, antidotes, safety constructions, 255-6-simple generators, 257-rotary force-blast, compression ejectors, 257-oscillating bellows, pneumatic compression ejectors, 257-reciprocating or pistoned ditto,
258-261-simple kind to construct, beer forcers applicable, Worswick Co.'s, Weindel's, Rumsey's, Douglas', 258-Daughtrey's underspray theory and machine, 258-261-the author's devices, 259-Weber's nozzles, 260.-V. SOLID COMPRESSION SQUIRTERS OF POISON, 261-283--kinds, 261 --rotary force pumps, 261-262-hydraulic bellows, 262-oscillating force pumps, 262--reciprocating force pumps, 262-283-kinds, 262-hydronettes and fountain pumps, 262-269-May's patent, Tyler's, Servants', Staples', Whitman's fountain pump, 263-hydronettes, double-acting, Deakin's, Rumsey's, cost, 264-author's improvements in knapsack apparatus, 264-5--in knapsack fire-extinguishers, Condict's and Doty's, 265-in horseback apparatus, Warner's, author's, 265-in cart or wagon, 265-8-Calahan's carts, legged wheels, tongue or shafts, 266-wagon use, Trelease's report, 266-8-more economic devices, 268-other pumps not in trade, 268-9-aquapults, aquajects, aquarius, excelsor, hydropult, 269-271-operation, cost, 269-aquapult, Johnson's patents, Douglas', Prouty's, '269-270Johnson's syringe, Douglas' aquarius, Rumsey's aquaject, 270-Deakin's excelsior, Vose's hydropult, 271-Bucket pumps and knapsack pumps, 271-4 -Lewis', 271-Korth's and less desirable kinds, Stoner's, Mallory's Kaiser's, Dix's, 272-Crandal's, Holland's, knapsack extinguishers, Douglas',






TABLE OF CONTENTS. IX

Page
MACHINElY AND DEVICES FOR THE DESTRUCTION OF THE WORM-ConLtinued.
Stanton's, 273-bucket poisoners, McDonald's, Allen's watering-pot improvem ents, 273-Amor's and Lane's can-syringe, Hull's, Wisner's, 274Barrel and tank punps and appurtenances, 274-283-Sinyle-acting, lischarging below the piston, Melcher's, 274-Voglesang's, Ruhmann's, 275Polansky's, Schier's, Butman's, Ball's agitator, 276-Evenden's, Helmecke's, 277-Yeager's pump and nozzle, 277-8-Pinter's, 278.-Single-acting, discharging from above the piston, Chipley's, Weith's, 278-available cistern or well pumps, 278-9-barrow pumps, ti uck pumps, garden engine pumps, windmill pumps, Blunt's Lotus pump, the Pendulum and Index pumps, counter pumps, 279.-Double-actitg, force pumps proper, 279-283-the best, 279, kinds characterized, Vose's hydropult, the Champion, 280-Rameden's, reduction-cylinder pumps, patentees and manfacturers, 281-2-author's agitator barrel-pump, found most satisfactory, 282-3-Conduits, frames, portage, and combinations of appurtenances, 283-Johnson's cotton-spraying minachine, 24-Jones's, inkley's, 285Goodin's, Wolfram's, 286-author's underspraying accessories, '28$plan, skid, mixing and straining funnel, 2 --adjustients of pipes, forks and nozzles, 289-29, fork modifications, -2-pendant pipes, 292, conformability, lightness, cheapunss, 292-3, tube substances, 293-author's Aframe machines, 293-7-maximum width undersprayed, 295-lpipe adj ustmentsto row widths, tiexible systes superior, -7-V. GRAVITATIONAL DISTRIBUTORS, 297-309-for liquid, 297-302-kinds, author's tripod automatic sprinkler, 297-8-Schank's sprinkler, Taylor's, 294-Robinson's, 299-suction force pmps and windlas elevators, -bilge pumps, 300horseback automatic sprinklers, watering pot method, Willie's sprinkler, 300-Ramsey's, 301-knapsack automatic sprinklers, 301-Gray's, Ruggle's, Townsend's, 302-automatic hand-sprinklers, watering- pots afoot and on horseback, 302-For dry poisons, sifters, kinds, 3(2-9-disadvantages, reciprocating sieve machines, hand-sieves, 303-4-sifting bag, Hurd's sifter and blower, Goodheart's duster and sprinkler, 304--rotary-sieve machines, 304-7-Robinson's duster and sprinkler, Davis' duster, Levy's, 305-Taylor's duter and sprinkler, 306-reciprocating-stirrer sifters, Willie's, 307-rotary-stirrer sifters, Young's, 307-Smith's, 30-Eldridge's,
309.
CHAPTER XIll.

MACHINERY AND DEVICES FOR THE DESTRUCTION OF THIE WORM-Concluded. 310
VII. INSECT MANIPULATORS, mechanical treatment, dislodgyig, crushing, or
stfling the worms or chrysalids, 310-sweeping, knocking, or jarring off the worms; friction drags, firings; beaters, 310-collecting and dispatching means, 311-crushing, Helm's sweeper and crusher, 311-Ewing's sweeper and stiffer, 312-Wood-Snmith's, 313-Iske's catching trays, 314traps for the moths, 314-321-kinds of lures, light traps, 314-Lewis', McQueen's, Rigel's, 315-Walker's and others, 315-6-lamps in motion, Leblan's, Fordtran's, 316-bait traps, Heard's, Garrett's, 317-traps combining light and bait, author's net trap, 317-319, thought the best, 318-indiscriminate killing wrong, the best bait, 319-Stith's trap, 319-Pugh's,
Garrett's, 320-Biukley's, 321.

CHAPTER XIV.

HISTORY OF THE LITERATURE AND BIBLIOGRAPHY.......................... ------------------32
History of the literature, 322-from 1802 to 182, 322-from 1829 to 1847,
323-from 1848 to 1854, 324-from 1855 to 1871, 325-from 1809 to 1874, 326-from 1874 to 17, 37fro 1878 to 1878, 7-from 187$ to 1880, 328-from 1880 to 1681, 329bibliography up to and including the year 1881, 329-344.






X TABLE OF CONTENTS.

CHAPTER XV.
Page.
INSECTS LIABLE TO BE MISTAKEN FOR ALETIA ..................---------------.......... 345
Confusion of Aletia with other moths, 345--with Aspila virescen8, 345-characters of the most important of these moths to be illustrated in this chapter, 345-list of these moths, 345--account of Anomis erosa Hiibner, 345-its geographical distribution, 346-structure of its eggs, 346-distinguished from egg of Aletia xylina, 346-its seasons, 346-habits of larva, 346-characters of moth, 347--detailed description of egg, 348-larva, 348--pupa, 349-seasons and food-plants, 349-account of Anomi8 texana, n. sp., 350habitat of A. exacta, 350-of A. texana, 350-larva distinguished from that of Aletia xylina, 350-pupa distinguished, 350-account of Leucania unipuncta Haworth, 350-reference to discussions about this species, 350-its geographical distribution, 351-oviposition, 351-food-habits of worms, 351-pupation, 351-number of broods, 351-hibernation, 351-account of Aspila virescens, 351-synonymy, 351-confounded with Aletia xlina only in pupa state, 351-pups of the two species distinguished, 352-foodplants of A. virescens, 352-moth distinguished from that of Aletia xylina, 352-account of Drasteria erechtea (Cramer), 352-its geographical distribution, 352-variations in size of moth, 352-food-plants of larva, 352habits of moth, 352-number of broods, 352-oviposition, 353-colors of larva, 353-account of Laphygma frugiperda, 353-its food-habits, 353synonyms, 353-account of Platyhypena scabra (Fabr.), 354-geographical distribution, 354.-food-plants, 354-number of broods, 354-reference to descriptions of larva, 354-Euplectrusplatyhypenw Howard, bred from larva, 354-account of Phoberia atomaris (Hiibner), 354-reference to descriptions
and figures of moth, 354-food-plant of moth, 354.

CHAPTER XVI.

THE BOLL WORM (Heliothis armigera Hiibner)............................... 355
Introductory, 355-one of the foremost of our injurious insects, 355-extent of its ravages, 355-nomenclature, 357-synonyms, 358-popular names, 358-geographical distribution, 358-food-plants, other than cotton, 359-corn, 359-tomato, 361-tobacco and other solanaces, 362--leguminosw, 362-cucurbitacew, 363-malvacew, 363-other food-plants, 363-characters and transformations, 364-the egg, 364-the larva, 365--the pupa, 370-the imago, 371-number of broods, 372-hibernation, 373-summary of the distinguishing points compared with Aletia, 374-egg, 374-larva, 374-pupa, 374-adult, 374-natural enemies, 375-remedies, 377-early planting, 378-low corn vs. high corn, 378-fall plowing, 378-destruction of the moths, 379-lights and poisoned sweets, 379--hand-picking,
380-poisoning, 381-pyrethrum, 381-bibliography, 382.

EXPLANATION TO PLATES .................... 385

Plate I-III, 385-IV-VII, 386-VIII-XI, 387-XII-XVI, 388-XVII-XX, 389XXI-XXV, 390-XXVI-XXVIII, 391-XXIX-XXXII, 392-XXXIIIXXXVIII, 303-XXXIX-XLII, 394-XLIII-XLVII, 395--XLVIII-LIII,
396-LIV-LVII, 397-LVIII-LXI, 398-LXII-LXIV, 399.






TABLE OF CONTENTS. XI

Pag,
APPEZEDICES...................... [1]

PREFA TO APPENDICES .................... .... .......... ................ [3]
APPENDIX I.
REPORT O If. G. HUBBARD ........................ ............ ............ [5
Report of observations made in 1881 upon Aletia and other insect enemies
of cotton, in the State of Florida, [5]-ootton injured more by Dysdercu aturellus than by Aletia xylina, [6]-and more by rust mite than by either, [7]-great destruction of Aletia eggs by Trichogramma pretiosa, [7]-succession of broods of Aletia, [7]-distribution of worms on plant, []-tabular statement of periods of time occupied in each stage of growth, [10j-locality of deposition of eggs on plant, [12]-proportions of light and dark colored worms, [2]-effect of shade in protecting cotton, [12]periods of different stages, [13]-copulation, [13]-position of moths at rest, [13]-experiments with poisons, [14]-pyrethrum, [14]-London purple, [13]-poisoning the moths, [ 15]-yeast, [16]-the boll worm, Heliothis armigera Hilbn., [16].
APPENDIX II.
REPORT OF PROF. R. W. JOE ......................----------...................... [17]
The cotton boll worm, Heliothiis armigera, [17]-its importance, [17]-foodplants, [17]-natural history, [18]-the egg, [18-the larva, [18]chrysalis, [19]-the moth, [19]-weather, [19]-natural enemies, [19]Cotton army worm, Aletia Tylina, [1l]-first appearance observed in 1880, [ 19 -experi nments with poisoned sweets, [20]-with adhesive sweets, [20]-gradual disappearance of moths in October, [20]-preparation of vegetable substances as insect icides, [20]-pyrethrum, [21 3-experiments
with pyrethrum [22].
APPENDIX III.
REPORT OF J. P. STELLE .................... -................................ [25]
First appearance of Aletia zylina and Heliothis armigera in Texas in 1880,
[251-cotn blight, [ 53-its symptoms, [25--its causes, [26]-boll rot, [26]-it symptoms, [27]-its cause, [27]-the flare, [27]-its symptoms, [27]-its probable cause, [27]-other food-plants than cotton for Aletia, [27]-none found for the larva, [27]-many for the 1moth, [27]-food of larva of Heliolkis armigtra, [2E]-annyances to the cotton worm, [28]common salt, [28 -saltpeter, [2]3-road dust, [28]-open spaces, [2]trees, [29]-shade, [29]-natural enemies, [29]-birds, [29]-ants, [!9]other insects, [30]-the yeast ferment remedy, [31]-pyrethrum powder, [31] -other vegetable poisons, [32]-arsenical poisons, [32]-London
purple, [32]-Paris green, [33]-arsenic, [33].

APPENDIX IV.

REPORTS OF Dn. E. 11. ANDERSON .......................................... [37]
For 180, [371-seasons and habits of A. xfylina, [37]-of Heliothis armigera,
[37]-localities of first appearance of A. xrylina in the season, [37]-reasons for this first appearance, [37], [38]-hibernation of this insect in some form, 138]-causes of undue multiplication of the worms, [38]-influence of ants on the number of worins, [3H]-habits of ants, [38]-other insects gathering sweets from the cotton plant, [39]-jute growing amidst cotton has no effect on the worms, [39]-Saturnia io found eating cotton, [39]-an enemy of the cotton worm found, [39]-experiments with London purple, [39]-with pyrethrum extract, [39]-with yeast, [40]-eggs of insects found on cotton leaf, [40]-characteristics of season of 1880, [40]-REPORT FOR 18t1, [40]-diary of observations on issuance, egg-






XII TABLE OF CONTENTS.

Page
REPORTS OF DR. E. H. ANDERSON-Continued.
laying, and hibernation of moths, and on weather, from October 3 to December 31, [40]-[44]-observations of BHeliothis armigera, [41]-[43]REPORT FOR 1882, [44]-observations on ants and aphides, [45]-abundance and sudden disappearance of Laphygma frugiperda, [45]-searcity of cotton worms, [45]-experiments with pyrethrum, [4&]-[48]--weather in September, [46], [47]-scarcity of Heliothis armigera in cotton, [46],
[47]-its preferred food-plants, [47].

APPENDIX V.

COTTON CATERPILLARS IN BRAZIL. BY JOHN C. BRANNER ................... [49]
Historical accounts of the occurrence of cotton caterpillars in Brazil,
[49]-[51]-influence of weather on the appearance and abundance of cotton worms, [51]-localities in which woims first appear, [51]-young cotton plants most injured, [51]-two species of cotton caterpillars have been confounded, [52]-seasons and relative abundance of the two, [52]duration of their pupa state, [52]-time of issue of moths, [53]-number of broods, [53]-enemies of the caterpillars, [53]-preventive measures, [53]-losses caused by caterpillars, [53]-[54]-Heliothis armigera scarcely
known to attack cotton in Brazil, [54].

APPENDIX VI.

REPORT OF JUDGE WILLIAM J. JONES .........----------------..--..--..............------------------- [55]
Obstacles to investigation in 1880, [55]-exemption of scattered patches of
cotton plants from depredation, [55]-answers to questions in Circular No. 7, [55]-[56]-cotton killed by a fungus, [56]-application of poisons to cotton, [56]-effect of poisons upon eggs and larve, [56]-no other insects observed to be injurious, [56]-use of lights recommended to destroy moths, [56]-[57].
APPENDIX VII.

REPORTS OF CONSULS AND CONSULAR AGENTS ON THE COTTON CROP AND ITS
ENEMIES IN MEXICO, CENrRAL AND SOUTH AMERICA, AND THE WEST
INDIES ....-----..-......---....--------------..........-------------------.............. ................... [59]
Introduction, [o9]-circular letter of inquiry, [59]-replies! from Merida,
Mexico, [60]-from Tampico, Mexico, [60]-from Martinique, W. I., [60]from Trinidad, W. I., [61]-from Manzanillo, Mexico, [61]-from Mazatlan, Mexico, [62]-from Bahia, Brazil, [63]-from Maricaibo, U. S. of Colombia, [64]-from Vera Cruz, Mexico, [65]-from Pernambuco, Brazil, [67]-from Bogot4, U. S. of Colombia, [681-Notes on insects injurious to the cotton plant in the Republic of Mexico, by D. H. Strother, U. S. consul-general, [70].
APPENDIX VIII.

ANSWERS TO CIRCULAR NO. 7----............................................... [71]
From D. M. Hamilton, St. Francisville, West tFeliciana Parish, La., [71]
-from R. A. Lee, Evergreen, Ala., [73]-from J. M. Wolkom, Henderson, Tex., [74]-from P. S. Clarke, Hempstead, Waller Co., Tex., [75]from L. D. Hoyt, Livingston, Sumter Co., Ala., [77]-from F. S.
Shields, Lake Concordia, Concordia Parish, La., [79]-from G. E. Gillespie, M. D., Natchitoches, La., [81]-from II. O. Dixon, Jackson, Miss., [84]-froim F. L. Yoakum, Larissa, Cherokee Co., Tex., [85]-from 0. H.
Perry, Perry Co., Ala., [86]-froim J. W. Grace, Walterborough, Colleton Co., S. C., [86]-from F. M. McMeekin, Jamestown, Alachua Co.,






TABLE OF CONTENTS. XIII


ASWER TO CIRCULAR NO. 7-Continued.
la., [87]-from H. P. Bee, San Antonio, Tex., [88], [89]-from E. H.
Anderson, Kirkwood, Miss., [90]-condensed summary of the habits of
the worm, from Dr. D. L. Phares, Woodville, Miss., [9-2].

NOTES .......... ...[.. 931
NOTE 1......................... ............ ........................ [95]
No 1r-----I-L-------------- ----------C--------------I----- -----Hibner's description of Aletia argillacea, with translation, [95].
No 2--..----......---- ----.............----------- --------------.......... ---- [95]
Reasons for rejecting HUibner's description of Aetia argillacea, [95]wherein this description and the figures differ from A. xylina, [95]-doubts of authors concerning A. argillacea, [953]-sarch for the type of A. argillaea, [96]-conditien of Sommer collection, [96]-how specimens of A.
xylina are labeled therein, [96].
NOTE 3-.... ..........--.-..----- .... ......... .-.....-- [96]
No published, full, and accurate description of the earlier states of A.
xylina extant, [96]-Reprint of descriptive portion of Dr. C. W. Capers' article "On the Cotton Caterpillar," ['97]-history of ravages of A.
zylina prior to 1828, [97]-sudden abandonment of cotton plants, [97]his description of moth, [98 egg, [9,]-larva, [9]-smell of larva, [98]-habits, [98]-food-plant, [9]3-pupation, [98]-description of pupa, [93]-remedies, [993-detailed description of egg, [99]-six stages of
larva, [99]-pupa, [100].
NOTE 4 ..-........ --............ ............................................. [100]
Difference in structure of prolegs, distinguishing Al eLt xylina from Aniomi
texana, [100].
NOTE 5 ....---- ...... .............-....... .................................. .. [100]
Repiblance of larva of Plusia dyaa to that of Aletia y ylina, [100]-proportion of light and dark specimens early and late in the season, [100].
NoT 6....- ----- ---------- --...----- -------.-. [.1001
Cotton leaves blotched by young larva of Spilosoma acrca, [100].
NoQ r 7 ..........-........................................................... [100]
Larva of Aletia xylina fed on Ip maa commutata, [100]-Abitilon and Phytolacca defoliated by different larva, [100]-said to feed on salve
bush," [100].
NOTE 8 .-.--- .L. . . -[100]
Structure of male genitalia of Ale a xylina, [100].
NOT 9 ....................................---...............----------................ [101
Noticeof Win. Treleae's Nectar: what it is and some of its uses," [101]teleology and dysteleology of nectar glands of cotton plant, [101].
NOTE 10. ......----------...................----......-----...--......----...------......-----------------............ [101
Rapidity with which the broods of A. xylina follow one another in midsummer, [101]-time of first appearance of worms, [101]-number of broods, [101]-prolificacy of moth, [101]-importance of natural checks
upon its increase, [101].
NOTE 11-- .................................................................... [101]
Influence of winter temperature on time of first appearance of worms, [101].
NOTE 12 .................................................................... [101]
Theories of hibernation of A. xylina, [1011-proof of hibernation of moth,
[102]-importance of this proof, [102].
No K 13 ......- .............................................................. [1023
Influence of latitude upon time of hatching of insects, [102].
NOTE 14 ....................................................--------------..---..--------....-----------........ [102
Number of broods of A. xylina previously recognized, [ 1021.






XIV TABLE OF CONTENTS.

Page.
NOTE 15 ...-------.---- -----..-------..------------------------------. [10-2]
Possible food-plants of larva of A. xylina, [102]-there must be some besides cotton, [102]-failure to find any other, [102]-feeding of larva of
Anomis erosa on Urena lobata, [102]-value of fiber of U. lobata, [102]geographical distribution of U. lobata, [103]-eggs and larva of Anomi erosa distinguished from those of Aletia xylina, [103]--examination of malvaceous plants in herbarium of U. S. Department of Agriculture, [103] -disadvantages of such an examination, [103]-plants on which eggs were found in the herbarium, [103]-petition for aid in obtaining eviden ce of the food-plant of A. yjlina in the more northern States, [103]list of malvaceous plants growing in these States, with localities, [103].
NOTE 16 .---------..-------. ---------------------------------------- [104]
Description of larva of Aspila virescens, [104].
NOTE 17 ............................-----........---------.......---------......---........----------.-----....--......-------- [104
Travels of E. A. Schwarz in 1878 and 1879, [104]-reference to published
accounts of the results of his investigations and those of others on hibernation of A. xyhna, [104J.
NOTE 18 .........................................------------------------------------------..---------------...................... [104]
Platyhypena scabra, [104]-characters of larva, [104J--food-plants of larva,
[104]-pupation and hibernation, [104]-characters of pupa, [104].
NOTE 19 .................................................................------------------------------------------------------.... [104]
Seasons of larva of Phoberia atomari8, [104].
NOTE 20 --........------..---------............-----.......----...----.---........------.........-----------..............---.... [104]
Criticism of paper by A. R, Grote on hibernation of A. xylina, [104]-Grote's
arguments against hibernation, based on experience gained in the same regions which furnish arguments against the theory of annual imuigration, [105]-possibility of hibernation admitted by Grote,f[105].
NOTE 21 ........................................-------------------..............---... [105]
Definition of northern and southern portions of cotton belt, [105].
NOTE 22 ------....--.......------........----.....--------------............--..-------..-- ....--.... ........--------...--.... [105]
References to discussion of J. P. Stelle's claim to have first recommended
publicly the use of Paris green for A. xylina, [105].
NOTE 23 ...........----------..-----..........----------------.................................... [105]
References to descriptions and figures of brush-sacs of moths, [105].
NOTE 24 ....................----...........--------------.....--. .---...........----------...... ....... [105]
Worms worse in wet weather than in dry because more protected from enemies, [105]-localities of first appearance of worms are those of least
molestation, [105].
NOTE 25 ................. ........... ........................ .. [106]
Appetite of swine for cotton worms, [106]-worms eaten by dogs and cats,
[106].
NOTE 26 ..........................................................-------------------.......... [106]
Reference to list of birds of southern States, [106].
NOTE 27 .........---........................................................ ---[106]
Range of English sparrow in United States, [106]-in hotter portions of the
country it is confined to towns and villages, [106].
NOTE 28 ...--.... .. ...................................... ---....... ...... [106]
Report by Dr. Geo. Marx on spiders found on cotton, [106]-preliminary
list of spiders which destroy insects noxious to agriculture, [106]-list of spiders observed to devour larvae of Aletia xylina, [106]-how they capture their victims, [106]-fod habits of Theridula sphaerula, [107]-observationls on habits of Oxyopas viridans, by I. G. Hubbard, [107]-ants
captured by larvwi of a Cicindela, [107].
INOTE 29 .. ... .. ...... ................... ...... ............. .., ... 1107]
Des~ciptiou of imago of Trichogrammna pretioa, 1107].






TABLE OF CONTENTS. XV

Pags.
NOTE.... ........----....--.... ........-------....--....--........--..--....--............- .... [107
Metamyusar n. g. and At. aleurnois n. sp., provisionally named, [107].
NOTE3 [1083
Description of imago and larva of ApanteLes aletia, [108].
NOTE 31 ........................ ...... ...................................... 108]
Apanteles aletie parasited by Eupelmus sp., [ 108].
NOTE 3 . I I III I I I .II .. .... I IIIII II [1083]
Description of imago of Eeplectru8s com1 ockii, [101].
NOTE33 [108]
ii-- -- ii -r II I -I I l-C---- ii* I II- iII I.IIII L Ir T I II I II I--- I II .f ll ..
Description of imago of Elachistus euplectri n. sp., [108].
NOTE34 .................................................................... [1o9]
Sarcophagi sarracenia distinct from S. carnaria, [109]-points of difference
between the Sarcophage of America and Europe generally, [109)]-additional specific characters of 8. arracenia, [109(].
NOTE 35 .......... .......................................................... [109
Description of imago of Tachina aleti, [109].
NOTE 36 ...... -......--- -...... ....-- ...... ......---..... .......... .... .... .... -.... --[109]
Description of imago of Tachinafraterna, [109].
NOTE 37 .................................................................... [1091
Differences between Tachinid larva and that of Sarcophaga, [109]-differences of puparia, [109]-reference to description of larva of Snonmetopia atropirora, [110]-of larva and pupa bf Tackina rillica, [1 10J-description of larva and puparium of Sarcophaga sarracenita, [110]-of larva of Belvoisia bifasciaia, [110]-difference of larva of B. cifaciata front that of Tachina concinnata, [110]-structure of spiracles in normal form of Taciinid puparium, [110]-description of the puparium, [110]-of puparium of Belroisia bifaciata, [111].
NOTE 8 ....... ................ .... .... .................................... [111
Synonymy of Cryptus conqui-itor, [111]-C. pleuriCinrtus erroteously given
as a synonym of C. annulicorwia, [111].

Synonymy of Cryptu8 eamie, [111].
NOTE ......--............................--......----------............................ --[111]
Description of larva and pupa of Chalke orata, [111]-list of lepidoptera
parasited by CA. ovata, [111]-variations in size of imago, [111].
NOTE 41 .- -. .. ..------- ------.. ---. .--. -- -- 1111
Synonymy of Tetrastichus eewrus, L1111-description of imago, [111].
NOTE42 .................................................................... [111]
Description of imago of Hexaplabta zigzag, [111-difficulty of defining the
families Chalcididw, Proctolrpide, and Cynipidc, [112]-food habits of
these families, [112].
NOTE 43[ ---- ..- -- ----- - ------. -1123
Phora aletia not a true parasite, [112]-habits of this species, [112].
NOTE 44 .......................... .......................................... [112]
The vast majority of the moths attracted to light said to be males, [112]if this is so, the usefulness of fires and lights as a remedy is almost
nothing, [112].
NOTE 45 .................................................................... [112]
Antidotes for arsenical poisoning, [112].
NOTE 46 .................................................................... [112]
Non-fertilized blossoms destroyed by morning showers or spraying, [112]when to make wet applications of poison, [112].
NOTE 47 [.......... .................. *,,, ,, , ,,, ,,., 113]
Test of purity of Paris green, [113.






XVI TABLE OF CONTENTS.

Page.
NOTE 48 ............................----------- ------------ ----... -- ........ ----------------------- 113
Proportions of Paris green mixture, [113].
NOTE 49 .--------------................. ..........----...............------------------.......--- .------. ------..... [113]
Effect of kerosene and kerosene emulsion on cotton plants, [113].
NOTE 50 -------------------------------------------------------- [113]
Pyrethrum willemoti probably a synon} m of P. roseum, [113] -reference to
Willemot's paper on P. willemoti, [113].
NOTE 51 ...........--------------------------------------------------------.. [113J
Growth of productive pyrethrum industry in California, [113]--effect of
pyrethrum on warm-blooded animals, [113]-pyrethrum recommended
as a disinfectant and germicide, [113].
NOTE 52 ..-- .-------------------------------------------------------- [113]
Cost of production compared with price of pyrethrum, [113].
NOTE 53 .-........ .. .... .... ....- .... ....-..................- ..... [113]
Enemies of Aletia xylina killed by poisoning the worms, [113].
NOTE 54 ...------------...............--------...-----....................................--------------------------------...... [113]
Positiveness with which various plants have been recommended as insecticides, [113].
NOTE 55 .................................................................... [114]
Insects injuring dog fennel, [114].
NOTE 56 .................................................................... [114]
Tests of spraying machinery, by Dr. W. S. Barnard, [114]--difficulties in
the use of machinery in irregularly-planted fields, [114]-means of overcoming these difficulties, [114 ]-conveyances for underspraying apparatus, [115]-management of apparatus, [115]-rapidity of service, [115]quantity of poison required, [ 115]-success of stirrer-pump device, [115]construction of stirrer-pump, [115]-construction of nozzle-pipes, [116]adjustment of these pipes, [116]-success of eddy-chamber nozzles, [116]-a closed system of pipes advisable, [116]-high pressure should always be used, [117]-adjustment of descending pipes, [117]-flexile joints recommended, [117]-advantages of flexile pipes, [117]-lifting of descending pipes in turning, [118]-devices for lateral shifting of pipes,
[118]-summary of conclusions from experiments, [118].
NOTE 57 ...............----------------------.....................---------------...-----......---------...--------------................... [119]
Recommendation to use Paris green in 1872, [119]-extract from report
made on this subject by J. P. Stelle, in 1880, [119]-comment on the
same, [120].
NOTE 58 ................................................................... [120]
Description of imago of Anomi8 texana, n. sp., [120].
NOTE 59 ......-............. .---- --.......-------------............... [120]
Description of egg and pupa of Drasteria erechtea, [120].
NOTE 60 ........................................ ............................ [121
Reprint of J. W. Boddie's description, in 1850, of imago of Phalaena zea
(Heliothis armigera), [ 121].
NOTE 61 .................................................................... [121]
Reprint of A. R. Grote's description of Heliothi8 umbro8us, [121].
NOTE 62 ........ ............... ...... ............ ........................... (121]
Remarks on specimens sent from Bahia, by R. A. Edes, in 1880, [1211characters of egg, larva, and pupa of Anomi8 sp., [121]-insects found in
cotton bolls, [121].
NOTE 63 .................................................................... ---121
Probably Macrosila ru8tica stated to feed on cotton, [121].
NOTE 64 ...................................... .... ........................ [121]
Larvm of .1 letia xylina received from Vera Crlz, (121 --recurren.ce of cotton
worms at irregular periods, [122].





















LETTER OF SUBMITTAL.



DEPARTMENT OF AGRICULTURE, DIVISION OF ENTOMOLOGY, Washington, D. C., March 15, 1884. SI: On behalf of the United States Entomological Commission, and in accordance with the act of Congress approved March 3, 1881, which provides that the reports of said Commission he made to the Commissioner of Agriculture, I have the honor to submit this, its fourth report.
Respectfully,
C. V. RILEY,
chief U. S. E. C.
Hon. GEORGE B. LORING, Commissioner of Agriculture.




















1I



































MEMBERS OF THE COMMISSION.

C. V. RILEY, Chief.
A. S. PACKARD, Secretary.
CYRUS THOMAS, Di8bursing Ageut. IUn












PREFACE.



The present volume is the fourth of the reports of the Commission, and was originally designed as a revised edition of Bulletin 3, and a final report on the subject of the Cotton Worm. A single chapter has been added on the Boll Worm, because of the importance of this species, but other insects affecting the cotton plant are only treated of incidentally. A good deal of material has been collected bearing on these other insects affecting the plant, and we hope some day to find time to prepare it for publication. But all work except that on the two principal insects treated of in this report has been considered of minor importance, -the main object of the inquiry being as full and accurate knowledge as possible respecting those two, especially in reference to their control or ready destruction by the planter.
The sifting of truth from error; the settlement of mooted questions by test and experiment; the discovery of previously unknown facts and truths, even regarding an insect like the Cotton Worm, require an amount of labor that few will appreciate who have not experienced the (ifficulties involved; and whatever merit this report may have is due to the fact that the author, in prosecuting the work, has earnestly sought to get at the exact truth, wherever there were conflicting views, experiences, or theories, and because it represents a very considerable amount of original research. He has also endeavored to bear constantly in mind that the chief object which Congress had in ordering the investigation was a practical one, and that whatever purely entomological knowledge was acquired, however interesting to the naturalist, was of less moment, unless it had some hearing on this practical phase of the subject. Hence, descriptive matter and technical discussions are for the most part excluded from the body of the work and printed at the end of the volume in a series of notes for the benefit of the reader who may be interested. Discoveries made in pursuit of some special object often subserve many other purposes and have wide application. This is eminently true in applied entomology, and many of the remedies and the devices for applying them that have resulted from this Cotton Worm investigation are of great use against many other species. This is well illustrated in the modern very general use by farmers and fruit-growers, in all parts of the country, of pyrethrum in the field, of petroleum emulsions, and of the cyclone spraying nozzle, all of which have had their origin in this investigation.
i i ..x.x.





XX PREFACE.

The character of the investigation was novel. There was no precedent to guide or warn. The number of persons capable, through experience, of intelligent field work in economic entomology was, until quite recently, remarkably small, so that the organization of the force to assist in the work was largely experimental and more difficult than it would have been had trained observers been at command. Under these circumstances, the satisfactory manner in which, with rire exceptions, the different agents have performed the tasks assigned to them is all the more to be commended. Many of these agents have been employed for but a limited time (about three months a year) or to make some special observations or experiments, and the results of their labor are either incorporated in the text of the report or in the appendices. Their work will also be found acknowledged in the introduction, in which we have endeavored to give an epitome of the history of the investigation as well as a glance at the contents of the volume. To all of them, and to the many correspondents who have so willingly and generously assisted, we take this public opportunity of tendering our sincere thanks.
To those who have been more permanently associated with us in this work we desire to express our special acknowledgments and indebtedness. Mr. E. A. Schwarz, from Detroit, Mich., has assisted from the beginning both in field and office work, while since the publication of the first edition Dr. W. S. Barnard, from Cornell University, Ithaca, N. Y., has also been continuously associated with us, and particularly in that phase of the inquiry pertaining to mechanical appliances. Mr. H. G. Hubbard, of Detroit, Mich., Mr. William H. Patton, of Waterbury, Conn., Prof. R. W. Jones, of the State University, Oxford, Miss., Judge L. C. Johnson, of Holly Springs, Miss., Prof. J. E. Willet, of Mercer University, Macon, Ga., Judge J. F. Bailey, of Marion, Ala., Judge W. J. Jones, of Virginia Point, Tex., Prof. E. A. Smith, of the State University, Tuscaloosa, Ala., Dr. E. f. Anderson, of Canton, Miss., Mr. James Roane, of Washington, and Dr. J. C. Neal, of Archer, Fla., all deserve special acknowledgment.
In addition to the observers mentioned, we are indebted to Prof. E. W. Hilgard, of the University of California and special census agent, for permission to use, in the preparation of Professor Smith's chapter and in advance of publication, the notes and observations made by himself and other special agents, while collecting the materials for his Report on Cotton Production in the United States. Mr. E. S. Burgess and Dr. C. S. Minot, of Boston, deserve our thanks for their services in the preparation of Chapter V, and Dr. J. C. Branner and Mr. Albert Koebele for their work in Brazil.
Last, but not least, we would express our indebtedness to those of our office assistants who have in any way contributed to the report: Mr. L. O. loward for general assistance in the preparation of the report Mr. Theo. Pergande for care in the breeding of the insects consigned to him, and Mr. B. P. Mann for clerical aid, especially in the preparation of the index.






PREFACE. XXI

The colored plates illustrating the report were either drawn by the writer or by Miss Lillie Sullivan under his immediate direction. Plate IV is reproduced from Glover's copper-plate etchings; Plates VI to XI were drawn by Messrs. Burgess and Minot from material furnished for the purpose; Plates XIV to LXI were either adapted from patent drawings or photographs, or were drawn by Dr. Barnard or by us either from the original machinery or from photographs thereof; Plate LXII is made up from drawings of our own, and Plates LXIII and LXIV were drawn by Dr. George Marx.
V. R.




































































































































































i9

















INTRODUCTION.




The official Cotton Worm investigation, of which this is the final report, was begun in the spring of the year 1878, Congress at that time having appropriated the sum of $5,000 to be expended for the purpose of such an investigation under our direction as entomologist of the United States Department of Agriculture. The results of the first nine months of the investigation are summed up in the following quotations from our report as United States Entomologist for the year 1878. The quotation also includes the first circular issued in the progress of the investigation:

INSECTS AFFECTING THE COTTON PLANT.

Pursuant to an appropriation by the last Congress for the purpose, and in accordance with your instructions, I have carried on a special investigation of the insects injuriosn to the cotton plant. The commission of inquiry was organized by the appointment of the following gentlemen: As special agents, Prof. J. H. Comstock, of Ithaca, N. Y., whose position as professor of entomology in Cornell University and whose ex-. perience with insects injurious to vegetation had well fitted him for such labor; and Prof. A. R. Grote, of Buffalo, N. Y., whom a residence of several years at Demopolis, Ala., and a special study of the Cotton Worm, had also well prepared forthe inquiry. As local agents and observers: Dr. E. E. H. Anderson, of Kirkwood, Miss.; William J. Jones, of Virginia Point, Tex.; Prof. J. E. Willet, of Macon, Ga.; and Prof. Eugene A. Smith, of Tuscaloosa, Ala. Mr. E. A. Schwarz, of Detroit, Mich., has also been engaged during the winter to visit all the Southern States and the West India islands, with a special view of getting at the facts of hibernation. To Professor Comstock was assigned the cotton region of Arkansas and Tennessee and of Mississippi and Alabama north of Vicksburg and Meridian and the Alabama Central Railroad; to Mr. Grote that of Florida and Georgia and of Alabama south of the railroad mentioned; while, with the assistance of the local observers, I have myself given more especial attention to the extremities of the belt, viz: Texas, Louisiana, Southern Mississippi, and the Carolinas.
The following circular-letter was prepared for the use of agents, and distributed, with corresponding blanks, to correspondents in the cotton belt. It will explain the scope of the inquiry:
DEPARTMENT OF AGRICULTURE,
Washington, D. C., July 22, 1878.
Sin: The entomologist of the department having prepared a series of inquiries for the special scientific observers to whom has been assigned the duty of studying the history and depredation of the worm known as Aletia argillacea, as well as other inects which injur the cotton plant, I have caused copies of these circulars to be printed and sent you, in hope that you may feel interest enough in the subject to make report thereon.






XXIV INTRODUCTION.

Should you do so, please observe carefully the following suggestions:
Write only on one side of the paper blanks sent; and, if more room is desired to answer fully, write on another sheet, numbering and lettering to correspond with letter and number of question.
If any special points arise before the termination of the season, please communicate freely, marking your envelope "cotton insects."
Respectfully, &c.,
WM. G. LE DUC, Commissioner.

THE COTTON WORM.

This insect (Aletia argillacea,* Hiibn.) will naturally receive most attention, being, as it is, by far the most injurious of the different enemies of the cotton plant. Data are requested on all the following topics:

PAST HISTORY OF THE COTTON WORM.
1. Give, so far as you can from trustworthy records, the earliest year in which cotton was grown in your State, county, or locality.
la. During what year (exact or approximate) did the worm first make its appearance in your locality, and, as far as you are aware, in the State; in other words, how many years elapsed after cotton first began to be grown before the worm began to work upon it ?
lb. Specify the years when it has been unusually abundant and destructive.

INFLUENCE OF THE WEATHER ON THE INSECT.

2. State what you know from experience of the effects of weather on the insect, and more particularly2a. The character of seasons most favorable to its increase.
2b. The character of the summer and winter-whether wet or dry, mild or severethat have preceded years in which the worm has been abundant and destructive.
'2c. Do wet summers favor its multiplication ?
2d. Effects of different kinds of weather on the eggs.
2e. Effects of different kinds of weather on the moths.
'2. Month of year when greatest injury is done.

STATISTICS OF LOSSES.
3. Give, as correctly as you can, estimates of the loss to the crop in your county and State during notable cotton-worm years.

MIGRATION OF THE MOTHS.

It is a well-established fact that the parent moth of the Cotton Worm is often found in autumn many hundred miles away from the cotton belt, and there is no reason to doubt that it is often carried by favorable winds to northward regions, where it cannot perpetuate its species and must therefore perish. Mr. A. R. Grote and others even believe that the species perishes each year with the plant, and that the moth always comes into the cotton States from more southern countries, where the cotton plant is perennial; in other words, that the moth is habitually migratory, and cannot survive the winter in the great cotton regions of the States. While there are many facts that lend weight to this theory, there is also much to be said against it; and we desire to collect all facts that in any way bear on the question. While we hope to get much valuable information on this head from the Signal Bureau, we also ask for the experience of correspondents.
4. Please state, therefore, as nearly as you can from the records, the prevailing direction and force of the wind in your locality, first, 4a. In the month of February; second, 4b. In the month of March; third, 4c. In the mouth of April; fourth, 4d. In the month of May; fifth,
4e. In the month of June; sixth, 4f. Whether, in your opinion, there are winds from the south that are sufficiently strong and constant to counteract the prevailing trade-winds, which are toward the equator.

*The Noctua xylina of Say.






INTRODUCTION. XXV

4g. The prevailing direction of the wind from July till frost. 4h. The side of a field on which the worns first begin to work. 4i. Do local topographical features influence the extent of the worm's ravages? 4j. Does or can the wori feed upon any other plant than cotton, and have you ever known it to do so

IIABITS AND NATURAL HISTORY.

These have already been studied, and are pretty well known ; but experience will differ somewhat with locality, and we call attention to the following topics:
5. State the time when the first moths are noticed in your locality. 5a. Date when the first worms have been not iced in past years. 5b. Date when the last worms have been seen in past years, or were noticed the present year.
Sc. Number of broods or generations of the worms generally produced.
Sd. In what other situations besides the folded cotton leaves have you known the worms to spin T
5e. Have you ever known the chrysalis to survive a frost, or to be found in soud and healthy condition in winter
5f. Have you ever found the mthh hibernating or flying during mild winter weather?
5g. How late in the spring has the moth been found alive ?

NATURAL ENEMIES.

It is a little singular that no enemies of the Cotton Worm have hitherto been reported. That the insect has its enemies, both special and general, there can be little doubt, and we would ask particular attention to the following topics:
6. Are any birds, quadrupeds, or reptiles known to attack the insect in your locality ?
a. Are any predaceousinsects or parasites known to prey upon it, either in the egg, larva, or chrysalis state

REMEDIES AD METHODS OF DESTRCTION.

7. What has been the result of the efforts to allure and destroy the moths, and what methods have proved most satisfactory f Give your estimate of the relative value fbr this purpose of poisoned sugar, molasses and vinegar, and fires.
7a. Are the moths most attracted to sweetened substances when smeared onto trees, boards, &c., or when contained in vessels in or near which lamps may be lighted ?
7b. Are any flowers known to be attractive to the moth ? If so, specify them and their season of blooming.
7c. What do you know of your own observation of thminfluence of jute grown near or with the cotton ?
7d. Has any effort been made to destroy the moth in in its winter quarters ?
7e. Have any systematic and organized attempts been made to gather and destroy the chrysalides, or to facilitate their collection and destruction by furnishing inviting material for the worms to spin up in ?
7f. What has been done toward destroying the eggs ?
7g. Has anything been found more generally useful and applicable or cheaper than the use of the Paris green mixture to destroy the worms ?
7h. Have you known of any injurious effects following the use of this poison, either to the plant, to man, or to animals ?
74. State what you consider the best and most effective method of destroying them in your section.
7j. State the cost per acre of protecting a crop by the best means employed.
We shall be glad to receive figures, either photographs or drawings, of m machines or conrivances employed for the wholesale use of the Paris green mixture, either in the fluid state or as a powder; or any other kinds of machines or traps employed for the destruction of the insect. Model of such are still more desirable, and may be sent by express unpaid to the department.
OTHER COTTON INSECTS.

There are many other insects that attack and do more or less injury to the cotton plant. Many of these have been figured and referred to by the former entomologist to the department, Mr. Townend Glover, but there is much yet to learn of their habits and natural history and of the best means of subduing them. Specimens of all insects that may be found upon the plant are, therefore, earnestly solicited, with accounts of their work and habits and the amount of injury they do. These apecimens are best sent by mail, in tight tin or wooden boxes. If living (and all found






XXVI INTRODUCTION.

feeding on the plant should thus be sent) a supply of food should be inclosed with them; if first killed, they should be carefully packed in a little cotton, to prevent shaking and breaking.
Correspondents who desire to make especial observations with a view of replying to this circular, and who wish further information as to the best manner of preserving specimens, will receive assistance and further instructions upon communicating with the department.
CHAS. V. RILEY,
Entomologist.

Two circumstances have somewhat interfered with the inquiry, viz, the yellow fever and the general freedom of the plant from the Cotton Worm, the serious injuries of this last having been restricted to the cane-brake regions of Alabama and to the southwest counties of Georgia, especially the country between the forks of the Flint and Chattahoochee Rivers-the more malarious portions of either State. Its appearance in injurious numbers, both here and in South Texas, was from four to six weeks later than usual, and this was one cause of the small amount of injury done. The weather at the time of their greatest abundance was wet and interfered with the application of remedies.
Professor Comstock's observations were chiefly confined to that fertile cotton-growing region along the line of the Alabama Central Railroad, known as the cane-brake.', He reached Selina July 20. There he met many prominent planters, and from them collected important statistics respecting the occurrence of the Cotton Worm and the results of experiments in the use of remedies for this species. July 23 he began his field observations near Uniontown, Perry County, and from that time on, till the middle of October, he was constantly engaged in studying the habits of cotton insects on plantations in Dallas, Perry, Hale, and Marengo Counti es. His only absence from this region was from August 10 to August 15, when I directed him to make a trip through the State northward as far as Madison County, where much cotton is grown. Professor Comstock has prepared a full and valuable report, which will be incorporated in the final report of the investigation.
Professor Grote's operations will appear by the following extract from a brief report submitted.
"SIR: In accordance with your favor of July 18, in which you directed me to visit the States of Georgia and Florida for the purpose of making observations on the insects injurious to the cotton plant, I proceeded to Savannah and during the following month of August made examinations of cotton fields at different points between Savannah and Atlanta. Having charged me especially with that phase of the cottonworm inquiry which comes under the head of migrations, I directed my chief attention to making observations and collecting information on the appearance and movements of the Cotton Worm (A lelia argillacea).
"A careful survey of the plantation of Dr. Lawton, near Savannah, from August 1 to August 7, and the cotton patches in the vicinity convinced me that the worm had not then appeared. The statements made to me were to the effect that its earliest appearance was usually to be looked for about the middle of the month. Henry Gaston, engaged in planting cotton for nearly twenty years, said that the first brood of worms web up about the middle to the latter part of August, giving a second brood in September. The worm was first noticed in the stronger cotton on the bottom lands. * He had observed the moth before the appearance of the worm, but had never noticed it in the early spring.
"This testimony is given as a sample of the information collected from various individuals. While August seems to be the usual time for the appearance of the worm on the mainland on the coast of Georgia, in the neighborhood of Savannah, the testimony of Dr. J. S. Lawton, on the sea islands off the coast of South Carolina to the northward of Savannah, is to the effect that the worm appears sometimes as early as July and is then usually excessively injurious to the long-staple cottons.
In Southwestern Georgia the worm is noticed as early as the last week in June in some years, and the main damage inflicted in the State seems to come from this quarter. The worm occurs there every year, though the date at which it is noticed varies. The question whether the so-called brood' is the first appearance of the worm in any quarter has been raised by yourself, and is one which I hope to be able to pay close attention in the spring.
For the present we must accept the testimony that the worm seems to advance from Southwest Georgia over the western and occassionally over the central portion






INTRODUCTION. XXVII

of the State. t sees to come from Decatur to Baker, Calhoun, Dougherty, and Lee Counties. According to present testimony its appearance is not simultaneous over this section of the State, the southern portions being first visited.
"From testimony collected by myself in Athens, on the occasion of the meeting of the Agricultural Society of Georgia, the following counties are visited by the Cotton Worm every year, though the exact line is not, according to testimony, the same: Calhou, Decatur, Dougherty, Lee, Mason, Schley, Taylor.
"Counties in which the worm is not noticed every year are: Burke, Clarke, Fulton, Greene, Hacock, Jones,Jon Monroe, Putnam, ichmond.
f" It will be seen that the central portion of the State is les subject to to the devastation of the Cotton Worm than the southwestern and western. *
"I received in November, 1878, fresh instructions from you to proceed to Georgia r the purpose of ascertaining whether I could find eggs from the last moths on any portion of the plant, and any facts bearing on the hibernation of the moth. On the plantations near Savannah I found that the worm was first noticed the current year on September 4. I found a large number of the chrysalides yet on the plant on November 10 to 2.. The nights we frosty and the leaf withered and s(ant. In places sheltered by trees the leaf was still green, and here I found (November 16) a few eaterpillars not yet spun up. A large number of the chrysalides were empty; about 40 per cent. contained parasites. Less than a quarter of the chrysalides contained the undeveloped moth.
"Under your instructions I have visited the Georgia sea-islands during the end of November and beginning of December. J found that the worm had appeared this year in September as on the mainland, but later in the month. It had, also, not spread, and had attacked certain corners of the fields, where I now found the chrysalde. None of these contained undeveloped moths, but they were either empty or ichneumonized. There hlad been no second brood of worms on the islands, according to testimony collected by me, and which was borne out by my own observations.
"As the result of my late observations I may say that the fact is confirmed that ibe Cotton Worm passes the winter, when it survives at all, as a oth, and that that the last fall worms do not leave the plant to web up. The full history of the worm in Georgia can be made out when the country is fully explored in the spring and before the first appearance of the worn in numbers. It will then be made clear where the first large numbers of the worn come from; whether they are the results of fresh invasions of the moth or the product of a tirst generation from eggs of hibernate ing idividuals.
"Under your intelligent supervision of the inquiry, and with the facilities which you posse from different sections of the South, I have no doubt that this important matter will receive final and full elucidation.
"My thanks are due to Mr. Z. Bauers, of Saint Catharine's Island ; Dr. W. S. Lawton, of Savannah; Mesr. T. G. Holt, of Macon, Ga.; J. E. Itedwine, Hull County, Georgia I E. C. Grier, Griswolville, Jones County; J. Pinckney Thomas, Wayne's Bluff, Burke County, Georgia; State Geologist George A. Little, of Atlanta, Ga., and others, who have assisted me in my work.
Yours, respectfully,
"A. R. GROTE.
"Prof. C. V. RILEY,
"Entomologist, Departfent Agriculture."

Starting south myself the latter part of August, I passed through Tennessee to Mitchell County, in Southwest Georgia, and thence, during September, through the cotton sections of the southeastern part of that State and of the Carolinas and Virginia. I was at this time made painfully aware of the hindering effects of the yellow fever. One can scarcely conceive of the panic and excitement that prevailed, even in regions where there was little or no danger. But a few weeks before in the thicker cotton counties of Alabama and Georgia the prevailing topic of conversation, as I learned, was the work of the Cotton Worm. At the time of my visit its injuries were forgotten in the all-absorbing subject of the epidemic. Cotton fields were neglected, d in sight of stripped and spindling stalks one heard but the universal refrain-yellow fever, yellow fever. It seriously interfered with my own plans, and obliged me to avoid the very Mississippi cotton fields which I desired most to visit.
Notwithstanding this serious drawback to the resent years operations, much that is valuable and importat has been learned. * *

In fact, our chief efforts during this first year as United States Entomologist were devoted to this investigation, and a large amount of mate-






XXVIII INTRODUCTION.

rial had been accumulated for a special report on the subject, of which Congress ordered (March 3, 1879) 10,000 copies to be published. In the spring of 1879 the investigation was, by act of Congress, transferred from this department to the United States Entomological Commission, which was then under the Interior Department. Owing to difficulties which grew out of this action, we resigned the position of entomologist to the Department of Agriculture, under Commissioner Le Due, to take effect May 1, 1879, and at the next formal meeting of the Commission, in subdividing the labors of its members, this cotton-insect work was assigned to the writer. He has, therefore, had entire charge of the same, and is alone responsible for the work and for this report.
The historic facts just related have no interest here except as they necessarily bear on the investigation, which Congress evidently intended to be continued under the same direction as that under which it had been instituted. But, as we have just seen, a special report on the subject under the Department of Agriculture had been ordered. Under these circumstances it became very desirable not only that the work we had done on that report should be properly brought to a close, but that there should be no duplication of work subsequently and no conflict between the Department and the Commission. We left the Department with the hope that such would be the case, and in the appointment of Prof. J. H. Comstock as our successor we anticipated the realization of our hopes, not only because of his assurances to that effect and to the effect that those who had been associated with us in the office and were familiar with the work and our plans should be retained, but because he himself had done the most efficient field work as one of our assistants and was well qualified to complete the report.However much we may regret that those hopes were subsequently not realized, or deplore the subsequent action of the Department in actively continuing this special investigation and in opposing the Commission, it is sufficient, in this connection, merely to mention the facts.
Preparations were made, in accordance with the law, to continue the work under the Commission after July 1, 1879. The following circular was sent to correspondents:
[Circular No. 7.]
RELATING TO THE COTTON WORM.
DEPARTMENT OF THE INTERIOR,
OFFICE OF THE U. S. ENTOMOLOGICAL COmissioN, 18--.
Mr.
DEAR SIR: The undersigned has for many years keenly felt that there was great need of more accurate knowledge of the habits of the Cotton Worm (Aletia argillaea). and of the other insects injuriously affecting the cotton plant, as also of more satisfactory means of counteracting their injuries. Recognizing the vast importance of the subject to the people of the South, one of his first efforts, after accepting the position






INTRODUCTION. XXTX

of entomologist to the Department of Agriculture, in May, 1878, wa t commence a special investigation looking to those ends.
An appropriation to the Department was obtained for the purpose, and the investigationr carried on under his direction up to the time of his resignation, on the first of May last. Since that time Congres has required the United States Entomological Coaumision to continue the work, and said Commission, at a late meeting, decided to place this part of its work in his charge. On behalf of the Commission, he would, therefore, call the attention of correspondents to the following questions and topics, with i he request that answers thereto, or experience thereon, be returned to him some tun before October next.
ame corres ondents whom this circular will reach may already have answered a more detailed one, sent out last year by the writer while connected with the Department of Agriculture. He would beg such to again give their experience on the fewer topics of the present circular.
He will be glad to receive figures, either photographs or drawings, of machines or contrivances employed for the wholesale use of the Pari rn mixture, either in the fluid state or as a powder; or any other kinds of machines or traps employed for the destruction of the insect. Models of such are still more desirable, and may be sent by express, unpaid, to the headquarters of the Comuission. Correspondence is solicited whenever any expense must attend the carrying out of these requests, in order that authtority may b given to mae ta he utecesary outlay and thus insure the refunding of the amount.
Respectfully,
CHASE. V. RILEY,
Chief U. S. E. C.

1. During what year was cotton first grown in your State, county, or locality
2. HoNimany years elapsed after cotton first began to be grown before the worm began to work upon it
3. Is the worm most dreaded after a mild or after a severe winter
4. Do wet or dry summers favor its multiplication ?
5. What is the earliest date at which you have known the worm to appear in spring t
6. In what locations does it most of fin irt appear
7. What is your experience, and what are your views, as to the winter habits of the inset t
8. What natural enemies of the worm among birds, quadrupeds, or insects are you familiar with ?
9. What has been the result of the efforts to allure and destroy the moths, and what methods have proved most satisfactory Give your estimate of the relative value for this purpose of poisoned sugar, molasses, and vinegar, or other poisonous substances, and fires.
10. Are the moths most attracted to sweetened substances when smeared upon trees, boards, &c., or when contained in vessels in or near which lamps may be lighted
11. Are any flowers known to be attractive to the inoth? If so, specify them and their season of blooming.
12. What do you know, from your own observation, of the influence of jute grown near or with the cotton ?
13. Has anything been found more generally useful and applicable, or cheaper, than the use of the Paris-green mixture, or of arsenic in some form, to destroy the worms
14. Have you known of any injurious effects following the use of this poison, either to the plant, to man, or to animals
15. State what you consider the best and most effective method of destroying the worms in your section.
16. State the cost per acre of protecting a crop by the best means employed.
Correspondents trill confer afaor b umbring the rep to correspond with the quetios and by wriina on but one side of the paper.





XXX INTRODUCTION.

The appropriation was limited that year, and on that account a limited force of assistants was employed. Mr. Schwarz spent considerable time in the Colorado bottom, at Columbus, Tex., and later at Selma, Ala., with Mr. Patton. We spent some time at both places with these gentlemen, and visited a number of other points at which there seemed opportunity of gaining experience or information. But our time was much taken up with the office work of the Commission and with the preparation of Bulletin 3, or the first edition of this work. This was issued January 28, 1880, or within seven months from the time the Commission took charre of the work. A summary of the work of the year is given in the introduction to that Bulletin, from which we quote the following passage, by way of deserved credit to some of the earlier students of the Cotton Worm, and particularly to the first entomologist of this department, since deceased:
The need of such an investigation, and even of a much more thorough one than the limited means so far appropriated therefor by Congress have permitted, is, I venture to believe, made apparent from the following pages. Mr. Townend Glover, during his earlier connection, as entomologist, with the Patent Office and the Department of Agriculture, gave much time to the study of the insects affecting cotton, and published in the Agricultural Reports for 1854 and 1855 much valuable information there anent, which has been a text for most subsequent writings on the subject. The science of entomology was then in its infancy in this country, and Mr. Glover labored under many difficulties in the proper determination of species and in other ways, which necessarily prevented that scientific accuracy and thoroughness which is desirable. Yet to his labors and those of a few Southern men like the late Thomas Affleck, of Brenham, Tex., and Dr. D. L. Phares, of Woodville, Miss., we owe all that was known and in any way reliable on the subject up to within the present decade; while his copper-plate figures of the principal insects affecting the plant, of which figures he published in 1878 a limited number of copies for distribution at his own expense, are so admirable and instructive that it is cause for regret that they were not long since issued, with appropriate text, by the Department of which he was so long the entomologist.
It may safely be said that up to 1878 scarcely any facts had been added, by direct observation, to those which Professor Glover had published regarding the Cotton Worm twenty-five years ago.
Just before the issuing of Bulletin 3 a circular was sent through the State Department to consuls and consular agents in different localities in Mexico, Central and South America, asking for such particulars concerning the enemies of the cotton plant as might bear upon the question of annual immigration. The answers. to this circular were received too late for insertion in Bulletin 3, but they have been used in the preparation of Chapter IV, and will be found in full, together with the text of the circular letter, in Appendix VII, page [59] of this volume.
During the year 1880, by virtue of increased means provided by Congress, the investigation was carried on with more vigor. Among temporary employs engaged for special work, Judge W. J. Jones acted as agent in Southern Texas, Prof. I. W. Jones was engaged in Mississippi making extracts and decoctions of different native plants to be tested as insecticides, and also in making special observations on the






INTRODUCTION. XXXI

Boll Worm, while Dr. Anderson and Judge Johnson represented the Commission in their respective parts of the same State, making experiments themselves and also assisting Professor Jones. Mr. Roane was located for some time at Selma, Ala., making extracts and decoctions of various native plants in that region, while Judge Bailey represented the Commission in the cane-brake region of the same State, and was more particularly charged with what pertains to the food habits and hibernation of the parent moth. In Georgia Professor Willet made a series of experiments to test the value of fungus germs in the destruction of the worm. Professor Smith, of Tuscaloosa, Ala., was engaged in the work on the cotton belt, represented in Chapter VI. Prof. J. P. Stelle, of Mobile, Ala., spent nearly five months in Texas, traveling from place to place, under special instructions as to observations, while Mr. Patton, in addition to assisting in the office work, spent part of the summer at Selma, Ala. Here. also, MJr. Schwarz was stationed, as we found it convenient to make this point a sort of field headquarters for the work, especially the testing of remedies and remedial appliances. Mr. Hubbard was stationed in Florida, principally at Centreville and Crescent City. Dr. Barnard had his headquarters at Vidalia, La., in the early part of the season, making notes in portions of Louisiana and Mississippi, but Iater in the season joined the force at Selma, where he gave more particular attention to the machinery experimented with. Whatever time could well be spared from the office work of the Commissiou we devoted to field work, visiting during the months of July, August, September, and October the different agents, and personally aiding and suggesting in the carrying out of plans and instructions.
These instructions were given in special correspondence with the agents, as also in Circular No. 7, and in the following supplementary circular letter:

SUPPLEMENTARY INSTRUCTIONS TO AGENTS.
OFFICE OF THE U. S. ENTOMOLOGICAL COMMISSION, No. 1700 13th Street, Washington, D. C., July 30, 1880. In addition to instructions already transmitted to you, I hereby call your attention to a few important points which should have especial attention. In the application of poisons already known to be effectual the great desideratum is to ascertain the minimum quantity that can be used successfully. It is my intention to perfect appliances that will throw either an extremely fine mist or an almost impalpable cloud of dust from near the ground up among the plants and on the under side of the leaves.
Test, therefore, thoroughly, by a series of experiments, whether:
1. London purple, Paris green, or arsenic can be used without diluents by forcing them dry in minimum quantity, onto the plants, and ascertaining how much ground a pound of each may be made to cover.
2. If they cannot be used without dilnents, the minimum quantity of such diluents
necessary.
3. How far, by fine spraying, and economy in preventing wastage on the ground, the number of water to a pound of these materials may be reduced-the






XXXII INTRODUCTION.

idea being, in all these desired experiments, to reduce the bulk and expense of the diluents by forcing the poisons in finer and fewer particles up among the plants rather than down upon them, through small perforations, or (what will prove.preferable) crescent-shaped slits of various dimensions in nozzles that will bear great pressure from within.
4. Test how far, i. e., over how much ground, on the above principles, a pound of pyrethrum may be made to go and still prove effectual.
5. Ascertain, if possible, whether the moths are not killed by sucking at the glands where the plant is poisoned from below.
6. Ascertain the effects of these different poisons on the eggs.
7. Always note the difference in effect on the very young and the full-grown worms.
8. Observe well in the woods and in the neighborhood of infested fields if the Aletia larva can be found feeding on any other plant, searching particularly plants of the same family (Malvacew) or that to which cotton belongs.
9. Note and study any mites found preying on the eggs. 10. Send me a summary of the experiments made with yeast ferment or beer mash by the middle of August.
11. Study well the influence of ants in the cotton field and in how far they prove destructive to Aletia, especially to the egg or young larva.
Respectfully,
C. V. RILEY,
Chief U. S. F. C.

Another circular (No. 10) referred to other insects affecting either the root, stem, branch, leaf, involucre, blossom or boll, but, for reasons stated in the Preface, need not be repeated here.
In the meantime the work we had left unfinished in the Department, together with some additional work done by Mr. William Trelease under direction of our successor, had been prepared for publication, and was issued in August, 1880, by Professor Comstock as author, under the title: Report I upon I Cotton Insects j prepared j under direction of the Commissioner of Agriculture in pursuance of an Act of Congress approved June 19, 1878 j By I J. Henry Comstock I Entomologist to the Department of Agriculture Washington I Government Printing Office I 1879 1 This is referred to in the following pages either as the Department Report on Cotton Insects or as Comstock's Cotton Insect Report."
On July 1, 1881, the U. S. Entomological Commission was transferred by previous act of Congress from the Department of the Interior to the Department of Agriculture, and we were soon thereafter asked to resume the position, which we had resigned two years previously, of entomologist to this last Department, under whose auspices the investigation has since been carried on. The work in 1881 and 1882 was chiefly devoted to the preparation of the present report and to the testing and perfecting of the machinery that had been devised, the Cotton Conven. tion held in the autumn of 1881 at Atlanta, Ga., offering a favorable opportunity, and much time having been given to the preparation of an exhibit of such machinery, which the Commissioner desired should be made there. Such further experiments as were made with insecti-






INTRODUCTION XXXIIt

cides were incidental to those made previously, and have been recorded in the publications of the Entomological Division.
The preparation of this report for the printer was virtually finished by the end of 1882, aand we owe it to ourself and to the public to explain here the reasons for the delay in its appearance. The chief reason hai been the desire on our part to have all the more practical questions as satisfactorily settled as possible, and every one who has been engaged in such work knows how one experiment suggests and begets another, and how difficult it is to close up experimental work that one is deeply interested in. We also felt the need of more exact knowledge of the facts in referference to Aletia in Brazil as bearing on the hibernation and introduction of the species within the States. In pursuit of information upon these points and upon questions concerning tli cultivation of cotton in Brazil, Dr. John C. Branner, a gentleman familiar with Brazil through his connection with several exploring expeditions, was sent to that country with an assistant, Mr. A. Koebele, in the winter of 1882-'83. They remained there some four months and collected a large amount of interesting material, returning in May, 1863. Dr. Braner's preliminary report was published in Bulletin 4 of the Entomological Division, pp. 51-69, and that portion of his final report which treats of cotton insects forms Appendix V of the present volume. The remainder of his report is published in Miscellaneous Special Report No. 8 of the Department, under the title "Cotton in the Empire of Brazil; the Antiquity, Methods, and Extent of its Cultivation; together with Statistics of Exportation aid Home Consumtption."
Then during this time the third report of the Commission was being prepared and issued, while the labors of the divisional work since 1881 have been greater than ever before. We have, both from choice and from necessity, made the finishing of the literary work of the Commission, which expired June 3, 882, secondary to our duties as entomologist to the Department, and the gemrral work of the Division, together with the preparation of the bulletins and annual reports issued since 1881, have helped to increase the delay. Finally, there are delays incident to Government publication which thosa who have had experience with it very well understand, but which the outside public cannot well appreciate. The chief of these is that the Governmient Printer finds it necessary to set aside work on special reports during the sessions of Congress, so that the summer months are the best to get work done on such special reports-the time of year, unfortunately, when, from the very nature of the work of the entomological Division, the entomologist is most occupied with the prosecution of research and has least time for literary or editorial work. Yet the fact remains that the report proper was formally submitted in March, 1884, and the bulk of it was in type, with all the illustrations made, by the fall of that year. If the foregoing account of the investigation upon which this report is based and explanation of the delay in its appearance indicate some of the difficulties





XXXIV INTRODUCTION.

that have beset its preparation, it must be remembered that they are such as are incidental to most scientific work of an official nature, or done under the Government. We hope and believe, notwithstanding, that the work will prove of standard value to all in any way interested in the matter of which it treats.
Chapters I and II, pertaining to classification, nomenclature, destructiveness, characters, habits, and natural history of the Cotton Worm, are condensed as much as possible. The reasons for abiding by the specific name of the species originally proposed by Say are more fully given in Note 2 than in the text, and if the statements in regard to habits and natural history have at times the appearance of being dogmatic where they conflict with previous statement by others, it is because the facts have been so fully studied as to leave no room for question. The full hibernation of the species, within our limits, was not established till the spring of 1882, by our finding the newly-hatched worms the latter part of March on rattoon cotton in South Georgia and Florida, but. it was to Mr. Koebele's unflagging industry (chiefly at night), while stationed at Archer, Fla., for this purpose, that the hibernating moths were obtained during the months of December, January, February, and March.
Chapter III consists of a summary, with as little detail as possible, of the past marked appearances of the Cotton Worm in the United States chronologically given, and of the history of remedies proposed for it. The history of the literature is given separately in Chapter XIV.
In Chapter IV brief consideration is given to the distribution of Aletia xylina in other countries than the United States, showing that it is confined to the Western Hemisphere.
Chapter V, by Messrs. Minot and Burgess, treats of the anatomy df Aletia by two competent histologists, and while it will have interest principally for the scientific reader, it will prove a valuable contribution to a phase of the subject hitherto untouched.
Chapter VI, by Professor Smith, treats of the cotton belt, its general characteristics, and its peculiarities from meteorological, agricultural, arboricultural, and geological standpoints. This subject of the cotton belt and its characteristics is one that always interested us from the possibility that, after careful study, it might indicate the preferred hibernating regions of the moth. Its proper consideration required not only a thorough knowledge of the country, but geological knowledge which we did not possess, and it is doubtful whether one could be found more thoroughly fitted to consider it than Professor Smith. His work has shown, if anything, that there is not, as we anticipated there might be, any necessary connection between the surface characteristics of the country and hibernation. This last evidently depends more on mean .winter teinpe'ature and earliness of spring, and if any conclusion is warranted, it would seem to be that the dark, low, and rich soils most conducive to the increase of tih worm are not the most conducive to






INTRODUCTION. XX XV

the winter preservation of the moth, which finds its most favorable winter conditions in the sheltered pine regions and dry sandy soil covered with wire grass. But aside from this Professor Smith's chapter will have a deep interest for cotton planters.
In Chapter VII we have briefly considered the influences, direct and indirect, which the character and condition of the soil, of the plant, and of the weather have upon the first appearance of the worms and upon their increase and destructiveness-a subject, as the context shows, of no mean importance.
In Chapter VIII the natural enemies of the insect are treated of and their value as checks to its increase considered. The list is a long one, and those of its own class are treated of systematically. M"Ianny previous errors are here corrected and a number of pertinent entomological ficts for the first time published. When the investigation began not a single true parasite had been recorded by name, whereas over a dozen are here recorded.
In Chapter IX we have dealt with such preventive Ieasures rs re worthy of consideration by planters, while in Chalster X we have dealt at length with remedies i. e., with means of coping ith tllhe insect, whether in the egg, larva, pu)a, or imago state, hut nmorc lartiu1lrly with substances that may be used fr the destruction of' the worm. Tills is the chapter which wAl probably prove of greatest value to those for whom the report is lrim april intended, and we bespeak its careful consideration. While many substances are conslhidred which have no value whatever, yet negative results once established have a decided value in preventing future waste of time and energy in fit ile work and th matter of the chapter is based on original research and experiment. In treating of the use of yeast feirment or other fungus germs we have used essentially the language of the first edition. Time has only served to confirm us in our ol)inion of their practical futility in the field. The question of the practical use of these micro-organisms-these disea~segerms-as insecticides is a very fascinating one, and is much written about just now; but unfortunately it proves most alluring to those who have had the least practical experience in coping with injurious insects in the field, and is much more apt to assume importance to the closet theorists than to those who, from experience, are conscious of the difficulties involved in its applicability.
Chapters XI, X, X, and XIII treat of the machinery and mechanical devices which are in use or may be used for the destruction of the insect, whether direct or by facilitating the application of the various sustances treated of in Chapter X. No excuse need be offered for the relative length of these chapters, as, owing to its importance, by far the larger part of the time and means employed in the investigation has been given to this part of the subject. In the early part of the investigation we personally took pains to acquaint ourself with all that had been done in this direction, and studied not only the patents that






XXXVI INTRODUCTION.

had been issued for machinery to be used against the Cotton Worm, but. more particularly such as was actually in use in the field. A summary of the results was given in Bulletin 3 of the Commission. The variety of these inventions by Southern planters and the ingenuity displayed in many of them compared very favorably with what had been done in similar directions in other parts of the country, and two important facts were obvious and are worthy of emphasis:
First. Though there is every reason to believe that the ravages of the worm were proportionally as great before as they have been since the late war, yet all the more important inventions post-date that period. Prior thereto only the more primitive and ineffective means of destruction, such as hand-picking and the use of fires and lights in the fields at night, were resorted to.
Secondly. By far the greater number of the machines have been invented in Texas, and this is doubtless due to the circumstance that the worm occurs more regularly and more disastrously there than in other States. Both facts are indicative of the more healthy development of the South under free as compared with slave labor.
The more satisfactory maIclines in vogue were those which distributed the liquid poison in broadcast spray or sprinkle over the surface of the plants from some wheeled vehicle containing a reservoir for the liquid, which was either distributed automatically or by means of force-pumps. We soon became convinced that whatever improvements were possible must be, as indicated in our later instructions to agents, in the direction of spraying the under surfaces of the leaves and of reducing to a minimum the quantity of poison necessary to an acre, as also the labor necessary to apply it.
The more important of these aims was first foreseen by Mr. W. J. Daughtrey, of Selma, Ala., who, in February, 1878, in his letters patent (see pp. 253-9), fully realized the advantage of fine spray on the under side of the leaves. Although the very ingenious machine contrived by him and described in these chapters did not work as successfully as he had hoped, and was too elaborate, heavy, and expensive to prove practically successful, yet too much praise cannot be given Mr. Daughtroy for the clear manner in which he saw what was required and the skill with which he endeavored to put the principle to practice. It has !een our aim in this part of the work to develop simpler means, that lay be available to the average planter for attaining the same object, and we would more particularly call attention to the underspraying arrangements (descril)ed on pp. 288-293 and supplemented in Note 52. In orler to accomplish anything of value in this field of machinery, it was necessary that some competent person should be able to devote his entire time to carrying out our ideas and to such experimentation as the objects in view suggested or required. Experience had shown that a professional engineer was not best fitted fi)r the work, and we were finally fortunate in securing, in the summer of of 1880, the services of






INTRODUCTION. XXXVII

Dr. Barnard, who, in addition to his knowledge of natural history, possesses mechanical ingenuity of a high order. After giving some time to general observations in Mississippi and Alabama in the summer of 1880, he was called to.Selma the latter part of August, and charged with mechanical work. It was there and early in September that the cyclone-nozzle originated in our endeavors to contrive something that would throw a spray from the ground up. The question was discussed between us as to whether water forced tangentially into a flatened disc would rotate and issue from an outlet in a straight or in a spreading jet. Dr. Barnard took the latter view, and a disc, improvised bymeans of two watch crystals, so as to permit the motion of the liquid to be seen, proved that he was correct. The size and form finally adopted is the result of numberless subsequent experiments covering a period of nearly two years.
While we have always had a number of original ideas to carry out and our direction of this work has been active, yet Dr. Barnard's assistawuc was fertile floni the first, and there is so much that has resulted therefrom that the preparation of these chapters was finally assigned to him, and he deserves much of the credit that attaches to them. It was found expedient on account of the large increase of matter, to depart from the general arrangement adopted in the first edition w hich, while it had the merit of simplicity, did not pItrmit of so thorough a classification. Much of the material iij that first edition, is, however, used verbatim in these chapters and such is placed in quotation marks, so that any quoted passage without authority or credit may be understood as being from that edition.
In describing these various machines and contrivances, it has beeni the endeavor to bring to the notice of the planter all that are worthy of mention, and to point out their advantages and disadvantages and how they may be used most economically and efSctively. The planter can then judge for himself which he can most profitably adopt according as his own circumstances dictate. Many of the older machines and contrivances are thus mentioned or described (though now superseded by improved ones) because they are of interest from a historical point of view.
Chapter XIV gives a short account of the history or the literature on the Cotton Worm and closes with a ibliograplhy up to and including the year 1881.
In Chapter XV are illustrated and described some of those insects which either in the larva state, but more particularly in the imago state, are liable to be confounded, and in fact have often been confounded, with the true Cotton Worm. As the northern Army Worm (Leucania uniluncta) in the imago state is, from its color and frequency, most often thus mistaken in winter time, we have introduced a colored plate of the species to facilitate comparison.
Chapter XVI is devoted to the Boll Worm, and will be found to con-






XXXVIII INTRODUCTION.

tain a quite fill account of it, especially of its different food-plants other than cotton; of its habits, characters, natural history, and natural enemies. A summary of its distinguishing points as compared with Aletia; a full consideration of the different methods that are available to counteract its injuries, and a bibliography are also given. It is fortunate that the best methods of underspraying the leaves of cotton with poisons to destroy the A letia also prove, all things considered, the best means of preventing the injury to cotton of this Heliothis.
Finally, in the Appendices will be found such reports from agents and observers as have been deemed worth publishing as supplementary to the report proper. The tabulated replies to the first circular issued from the department are not included, as they were published in the Department Cotton Insect Report, while the more valuable of those in reply to Circular No. 7 are given in Appendix VII. As already stated, these Appendices include also Mr. Branner's report on observations made in Brazil, as well as the reports from consular agents upon the insect in other countries.
The Notes, as already stated in the Preface, either contain matter of a technical nature that it was deemed advisable to exclude from the main text, or matter needed to still further elucidate or supplement it.












CHAPTER 1.




CLASSIFICATION AND NOMENCLATIRE. DESTRUCTIVENESS.
POPULAR AND SCIENTIFIC NAMES.
Among planters the Cotton Worm is very often termed the Caterpillar," or the "Cotton Caterpillar." and not infrequently the "Army WWorrn." We have elsewhere shown* why this last term should be disounlltenanced in the literature of the sulject, unless prefixed by the word "Cotton," and, both ftir the sake of brevity and to prevent confusion, the mine used in this Iulletin, and by which the insect in this larva state is very generally known, is, on the whole, prel rable. In Louisiana, more particularly, the French term "clhenille," meaning caterpillar, is coninonly CemltN11 ed For the i erfect insect the term "fly" is more often used in some parts of the South than the term "moth," but the latter is preferable from an entomological view.
As to the scientific name, the species was first described by Thomas say, in 1827, as Noctua rlira, ill a letter to Dr. C. W. Capers, published in the Southern Ariculturc irt (vol. 1, p. 203), but overlooked by most later writers. harris, in his Correslpoenee, placed the "Cotton Moth" near the geluns Ophila, while later authors more correctly referred it to Illibne)'s genus Anomis. Mr. A. I. G(;rte, in 1ST 1,' ar ived at the conclusion that Say's xylina was nothing more nor less than lthe Aletia arTilea of Hiibner, described and figdrt by this author in 123;1. In this opinion he was followed by subsequent author, ald this name was adopted in Bulletin 3 of the Commrnission, and also in tie Special 'eprt of the Agricultural Dealrtment. Recent studies,2 however, indicate that, although our Cotton WVori nloth is found at Bhllah, th loca]lity from which A. argillacta was originally described, this namrie was, without much doubt, given by Illiiber to an entirely distinct species also found in the same localit y, andl Sy's specific name of xylina should still hohl for our Cotton Womn mioth.
Accepting thie difference between Anomis and Aletia as of generic value, our Cotton Moth should still be placed in Ahletia; and the common or popular name "Aletia," which wepjrpposed iln the Bulletinl, and which has come into quite extensive iuse in the last four years, may, theretfre, be retained.
*See Scon Annual n eport on the noxious benefal, and other insects of the State of Missouri, 1870,p.37.
tProc. Am. Assoc. Adv. Sci. for 1874, 1875, v. 23, See. B, p. 13-18.






2 REPORT 4, UNITED STATES ENTOMOLOGICAL COMMISSION.

We may briefly give the corrected synonymy of the insect as follows:
Noctua xylina Say, 1830.
Ophiusa (?) xylina (Say), Harris, 1851.
Anomis grandipuncta Guende, 1852.
Anomis bipunctina Guende, 1852.
Depressaria gossypioides W ailes, 1854.
A nomis xylina (Say), Grote, 1864.
Aletia argillacea lliibn., Grote, 1874.
Aletia xylina (Say), Riley, 1881, 1882.
Aletia xylina (Say), Brooklyn Society Check List, 1882.
Further particulars will be found in the Notes and in chapter XIV, which treats of Past History and of Bibliography.

CLASSIFICATORY POSITION.
The Cotton Worm moth belongs to that order of insects known as the LEPIDOPTERA, which includes all true butterflies and moths. The moths (Heterocera) are separated into a number of families, of which the Owlet Moths (Noctuid) form one of the most important. This family Noctuid is of great interest to the economic entomologist, for it contains not only the insect under consideration, but all the true Cutworms, the Army Worm, the Grass Worm, the Boll or Corn Worm, the Cabbage Plusia, and many others of scarcely less importance.23
DESTRUCTIVENESS OF THE WORM.
An impartial calculation of the money loss to the cultivator caused by injury to the great staples of the country from their insect enemies, is sure to startle us by its magnitude when the loss is aggregated. Such a calculation of the losses which the Cotton Worm (not to speak of other insects) inflicts on the people of the South, based upon the somewhat imperfect statistical data at command, leads to the following interesting conclusions, which for the most part receive explanation in the facts embodied in this report. The calculation embraces fourteen years after the close of the civil war, and was made by Mr. C. R. Dodge, and verified for us by Mr. J. R. Dodge, the statistician. Any extraneous causes which tend to retard the growth of the plant, also tend to swell the percentage of injury by the worm when it abounds. Where an early stand is secured, with thorough cultivation and exemption from other causes of injury, there the percentage of loss is least, even in bad Cotton Worm years. The percentage of loss is, also, dependent on location. When the injury is done early in the season, the loss in localities of heaviest production, or where thg fields are numerous and contiguous, is nearly double what it is where the fields are more isolated. In years of severe injury, from 30 to 98 per cent. of the crop may be ruined upon some plantations, while on others the loss will be trifling. The highest average 6f loss is sustained in the southern portion of the belt, as in Florida and southern Texas. It increases also in a westerly direction,






STATISTICS OF LOSSES CAUSED BY ALETIA. 3

commencing with Georgia at 16 per cent., or 16 bales out of every 100 of a average crop for fifteen years, and ending with Texas at 28 per cent. In the northern portion of the belt the averages are low, ranging from 5 to 8 per cent. for the same period; while in many parts of it, and notably in North Carolina, the worm appears so late as to generally do more good than harm by removing the luxuriant top foliage, and thus admittig the sun to the lower bolls and hastening their maturity.
The following table shows the amount of loss in bales and dollars for each State in a year of severe visitation:

Per cent of Cr LCrSe Money loss. fr ort yN ears.

State.



.......................................... 24 49, 2, 0 000
eorgia .. ................... ............. 25 1 15 16. 78, 2 0 9 t91,000
r t n................................. .... .. .. 1 5 17.8 G T 1 1. ") 4, 7- o 10(
i- .. .............. .. ................ 1 17 .7., I 8705 n, 4 000
............ .... 0 4. 70 8, 740 4 437, 0
Tt ca. :. :20 28 ........ ..... 5525, 'OO 148, 125 7, 416, 00
T a ln ................... ................. 2 3147.'0 J 411, 000



The terms "highest" and "lowesL" in this table do not refer to the greatest amount of injury or to the reverse inflicted in individual localities, but to a general average for the principal counties of heaviest production on the one hand, and the average for the remainder of the State on the other. These figures are derived from the statistical reports of the Department of Agriculture. The average for the State as a whole appears in the third column, made up from the same sources. The fourth column is made up from reports of the cotton movement. The table shows a possible loss, in years of great prevalence, of about $30,000,000. On this basis the average annual loss may safely be put down at about $15,000,00 for all the cotton States for the fourteen years following the war.
There have been two previous estimates of the loss occasioned by the worm, both of which bear out this table. In the report of the Statistician of the Department of Agriculture for 1877 the loss by the cotton worm was estimated for that year at $15,000,000, the greater portion of the los being suffered in Texas, though the damage was considerable as far et as Alabama. Notwithstanding this loss the year was one of unusual harvest, hence this estimate bears out well our estimate of the average annual loss. In the report of the Entomologist in the annual report of this Department for 1873 (p. 164) there appears a general







4 REPORT 4, UNITED STATES ENTOMOLOGICAL COMMISSION.


statement, also furnished by the statistician, which placed the amount of damage at possibly 500,000 bales in years of insect prevalence. This, at $50 a bale, would be $25,000,000, also closely approximating our estimate of the damage in worst years. The estimate of price at $50 a bale for the fourteen years succeeding the war is low rather than high, as the plantation prices between 1860 and 1870 ranged from $180 down to $60.
That the damage was equally great before the war there is no reason to doubt, for while severe visitations have, perhaps, been more frequent since that time, the injury has been greatly diminished by the use of Paris green and other arsenical poisons since the year 1873.
The subsidiary table of losses from the worm for the year 1881 illustrates this point quite well:

Loss of cotton by worms as reported in 1881.



stat Loe. Total, per Loe.



Bae. Balee. Per cent.
Alabam ...................................................... 40 51,349 509, 616 10.1
Arkan8..... ........ ................................ 45 15,055 407,342 3.7
Florida .................................. ................ ..... 16 4, 077 29, 623 18 8
Geort a ....................................................... 93 20, 958 582, 332 38.
Louisiana .................................................. 29 29, 649 273, 356 10.8
1isn-.niippi ............... .. ................................. 39 38,111 83, 763 6.
Missouri ......... .... ". .......... ....... .. 6 ........... 16, 135 ..........
North C(arolina ................................................ 56 204 346, 931 0.1
outh Carolina ................................................ 25 10, 233 413,943 2.5
Tennseee ..................................................... 28 1,374 146, 150 0.9
Texas ................ ......................................... 88 22, 472 561, 778 4
Vrginia ................................................ 4 ......... 7, 800........
Total ................................................ .... 193,482 3, 878, 769 5

Total cotton prdueed, 6,589.000 bales: total cotton produced in counties reporting worm, 3,.R.796 bales, or 5.9 of the whole crop. This would leave on ithe basis of the whole crop a loss of only 2.9%, or a mon1 y los of $,7006.690, calculating on $45 the bale, or $9,674. 100 on the former basis of $0. We would especiady call attention to the great reuctLion in the percentage of loss from 17.2 to 2.9+.











CHAPTER II.



CHARACTERS, HABITS, AND NATURAL HISTORY.
[Plate I. ]
The Cotton Worm, like most other insects, and all belonging to its Order and Family, exists in four distinct states, which (lifer much from each other. They are, 1st, the egg; 2d, the larra or worm; 3d, the chrysalis; 4th, the iiago or moth.
The worn MsT hatch from an egg deposited by the female moth. All theories to the contrary, such as its supposed spontaneous development from the plant, or its origin from the cotton-seed, are therefore utterly without foundation. They need emphatic denial here, because of their prevalence not only among the negroes and the more ignorant, but among intelligent men unfamiliar with the principles of biology. Such theories always have been, and doubtless always will be entertained in explanation of the apparently sudden appearance and rapid multiplication of any insect or other organism in which the p)relimilmry phases of the phenomena are easily overlooked or with difficulty traced. We will indicate the the characteristics of these four states, so as to enable the reader unacquainted with any or all of them to recognize the species in any phase of-its growth and to distinglish it from all other insects, and will give detailed descriptions of the different stages elsewhere,3 On Plate I, more particularly, we have represented, of natural size, all the different phases, as they may be observed in the field.

THE EGG.
The egg is 0.6mr wide, circular, much flattened and ribbed, as at Fig. 1. Of a bright bluish-green or sea-green when first laid, it contrasts sufficiently with the warmer green of the leaf to be easily detected, even by the naked eye when practised (Plate I, Fig. 1). It is laid singly, and fastened with such firmness as not to be easily removed without injury. It is laid by preference, during early sunm mer, on the under side of the larger and lower cc leaves, and seldom more than three or four Fl(, 1.--Ec o A LETIA: a. from above; are found on one leaf. In confinement and b, from side. (After Riley.) exceptionally in nature it will be laid on the upper surface of the leaf, or on any other exposed part of the plant. In autumn, more )particllarly, the upper leaves receive a due share of the eggs, and we have
5






'6 REPORT 4, UNITED STATES ENTOMOLOGICAL COMMISSION.

counted as many as 49 eggs and egg-shells on a single leaf. With development the color becomes more dingy, or nale yellowish, frequently with brownish borders or a green curve, due to the coiled embryo, which may be seen through the transparent shell. The young worm or larva eats its way out through an irregular hole on one side, usually during the morning, ere the dew is dissipated, and from three to four days after oviposition. This is the average time elapsing between the laying of the egg and the hatching of the worm therefrom in ordinary midsummer weather, but the time varies with the temperature, and a much longer period is required in spring and late autumn.
All eggs perish that are unhatched when overtaken by frost, as is not infrequently the case. The vacated and glistening shell is more readily noticed upon the green background than the unhatched egg. At Fi'g. 1 we have shown one of the more perfect eggs both from above
(a) and from the side (b), and greatly enlarged, so as to indicate the sc llture, the natural size being indicated between them.
Hiumnidity seems to favor hatching. Aphides or plant-lice are quite often mistaken ibr the eggs of this insect, while the "Mealy-bug" (Dactylopius sp.), a species of Aleurodes, the eggs of the Lady-birds (Coccinellilice), those of the Lace-wings (Chrysopa), and even a minute snail, not uncommon on the cotton plant, are likewise so mistaken.

THE WORM OR LARVA.

This, as it appears in its different stages ,of growth on Plate I, is familiar to every planter. Varying greatly in ground-color, it is characterized by the particular position of the black piliferous spots upon the head and upon the body; by
the white ring which surrounds each of these spots;
by its pure white subdorsal lines and by its elongate and slender form. It is a semi looper, the first pair of pro'I legs being very much reduced in size and seldom used,
and the second pair, though longer, only about half as
long as the succeeding pair.4
The worm molts five times during growth and changes appearance but little after the first molt. Exceptionally only four molts are suffered.
The newly-hatched worm measures 1.6mm, is of a FIG. 2.--NEW1.Y-HATCiHD uniform, pa!e dingy yellow, marked as in Fig. 2, with Cb, Oi wOuw. aftrack polished, black, slightly elevated spots, each bearing a Riley.) short, pale hair. Before the first skin is shed the color often becomes slightly greenish and sometimes inclines to orange. After the first molt thle piliferous spots are more conspicuous, the hairs from them longer and black, and the characteristic markings appear, though less distinctly than after the second; but from this time on the prevailing color is very variable, being either entirely of various shades of pale or pea-green, or more or less intensely black along the back.






HABITS OF THE LARVA. 7

The normal number of larval molts is five. This is the number which we have observed during the autumn months, while in midsummer, when the development is more rapid, we have on several occasions traced but four. The term of larval existence varies from one to three weeks.
There is a very general belief among planters that the first worms of the season are pale and the late ones dark, and while both light and dark worms may always be found together in spring, summer, or fall, it is true that the green ones predominate early in the season and the dark ones later.5
Immediately after molting, the body is pale and without marking-a rule with all molting animals. After the earlier molts, the cast-off skin which remains more or Ies fully stretched, is sometimes eaten.
Some of the peculiarities in the habits of the worm deserve mention here, because of their practical bearing.
Until after the second molt it always remains on the under side of the leaf, feeding upon the parenchyma, and leaving untouched the coarser veins, smalta, and upper skin or epidermis. The leaves where they are thus feeding present a blotched appearance, the semi transIarent epidermis becoming p)ale yellowish, and these blotches are, as a rule, at once distinguishable from other somewhat similar ones made by a few other insects."
After the worm begins to eat entirely throughthe leaf, which is usually before the third molt, but sometimes later, it instinctively ascinds e b toward the top of the plant and feeds on the Fa o .--t,ow:CoC Woel a a. from si b, from back; twi e
more tender foliage, "ragging" it, to use the natural size. (After Riey.) exl)resive language of the planter.
It can let itself down by a web from the moment of birth, but can also fling itself from one part of the plant to another in a manner quitee characteristic. The fling or jump is made by bending the fore and raised part of the body to one side and then suddenly jerking it to tihe opposite side, relaxing meanwhile the three hind pairs of legs by which it held to te plant. This is a quite common mode of motion when disturbed, and the normal way of getting from one plant to another. The maximumin distance which a worm can thus jump in a horizontal direction is about two feet, and it almost invariably alights on its legs. During chilly weather in autumn this motion is feeble and can be easily watched. When not feeding, the worm either rests stretched straight on some prt of the plant or may be seen swaying its fore body from side to side, holding the while by the hind prolegs.
Though preferring the foliage, it will, when hard pushed, eat every






8 REPORT 4, UNITED STATES ENTOMOLOGICAL COMMISSION.

exposed part of the plant, even barking and girdling the stems. In feeding on the bolls, however, it does not bore like the Boll Worm (Beliothis armigera), but eats the external parts as well as their contents. It is not known to thrive on any other plant than cotton, although probability points to the belief that there will yet be found one or two more such food-plants, both at the North and at the South.7
As one correspondent naively puts it, the worms feed only on cotton and one another," the cannibalistic propensity being freely indulged when the occasion presents. It is a common remark that the presence of the worm is easier detected by smell than by sight. The planter says that he can "smell the worm." There is a peculiar odor arising from the excrement, but particularly from the gnawed and. mutilated leaves, that gives rise to this saying; but where the worms are numerous and large enough to render it obvious, there they have already existed several days, perhaps weeks, in smaller numbers.
When numerous enough to utterly defoliate a field before they have attaied full growth, the worms will travel in all directions on the ground, and they have been exceptionally known to collect together and travel in vast bodies in their search for fresh food.

THE CHRYSALIS.

Having obtained full growth, the worm, in the language of the pIlanter, webs up," foring for protection a more or less perfect cocoon, usually within the fold or roll of a leaf sparsely lined with silken mneshes. Here it contracts and thickens, the distinctive marks are nearly obliterated, and the green color acquires a verdigris hue. Within twenty-four hours, in midsummer, the skin splits just back of the head, and is gradually worked to the end of the forming chrysalis, now soft and green, but acquiring in the course of an hour or more a brown color and firmer consistence. This chrysalis state lasts, on an average, about a week in hot, weather, but may extend to thrice that time with lower temperature. Where necessity obliges, the worm will spin up on any other plant or in any situation that offers shelter. In con- 1 finemnent it will make a cocoon on the 4surface of the ground, covering and disguising the same with particles of
Fim. 4.-CHRYSALTS OF ATLETTA: enlarged to
earth, or it will even tra:isform on the show cremiaster from the side (a) and from be. ground without silk or shelter. Such nath (b). (Afltr rle'.) cases rarely if ever occur itn a state of nature, but when the worms are very numerous in a field the chrysalides frequently have their leafy protection eaten away, so that many of them either hang by the few hooks at the extremity, or fall to the ground. In no case, however, does the worm burrow in the ground as does the Boll Worm, or could the moth issue from the chrysalis were the latter accidentally buried even an inch beneath the surface.






CHARACTERS OF THE MOTH. 9

We shall presently see, in discussing the hibernation of the species, that it is quite important to distinguish between this chrysalis and thers that closely resemble it, and to enable the reader to more readily do so an enlarged outline is here introduced.. The color varies from light mahogny-brown to deep purplish-brown, while the general form is that belonging to many other chrysalides. Neither form nor color can serve, then, as distinguishing traits, and the same is true of size. The peculiar form of the cremaster, or anal tubercle bearing the hooklets (Fig. 4), will prove the best and safest criterion, and any chrysalis found in a cotton ficld that has a different tip may be safely detel mined as not that of the Cotton 'orm. The duration of the chrysalis state also averages about fifteen days. We have known it to last but seven days, and Mr. Glover records its lasting thirty days.*

THE 1MOTH,1 OR IMAGO.

The moth measures from 1 to 1 inches from tip to tip of wings when these are expanded. Its general color, above, is oliva*eous, more or, less effectually subdued by lilacous or purple hues, and often having a clay-yellow or faintly golden east. The under side is more gray, with nacreous reflections. .....
The markings that more particularly eharacterize and distingu ish it from all other North American moths are certain undulating vinlous or carmine lines across tie front wings, a dark oval spot near their disc, containing pale scales which us uly form a double pupil (the basal or inner puplil the smaller and whiterr, and three whitespecks dirid- FI,. ,--O- LruY OF AiETTA: fin t he sp ce sowing charatr istic mai ks ad whBite specks (aaa)-twice natubetwe this dark ral size. (After Riley.) Sot and the shoulder in about three equal parts. (Fig. 5, a a a.)

able, as the relative stoutness of the male i antennla coinpared with those of the female is so slight as to be no safe guide. Au examination of the tip of the abdomen, especially from the side, will always show the difference, however, the last joint in o $ the male (Fig. 6, a) being the longer and e.-o; b, f oX MH: ale abd. more fll, and the p)ale tufts of hair that iley.) belong to the withdrawn genitalia showing within or beyond the squarely docked tip; while in the female (Fig. 6, b) this joint is shorter, more pointed, and obliquely truncate beneath.
*Report of Commissioner of Patents, for 1855; Agriculture, p. 73.






10 REPORT 4, UNITED STATES ENTOMOLOGICAL COMMISSION.

The habits of this moth can only be studied at night, as, like almost all the rest of its family, it is nocturnal. During the day it simply starts up when disturbed, and darts by swift and low flight to some other sheltered spot a few yards, or perhaps rods, away. After sunset, however, it may be seen leisurely hovering about, either bent on the perpetuation of its kind or feeding upon whatever sweets it can get, whether from the cotton or from other sources. It is very strong and swift of wing, and capable, when the necessity arises, of flying long distances. In alighting upon the plant it generally turns its head downward, and, when it rests, the wings are but shallowly roofed, the front ones closed along the back and fully hiding the hind ones. In this respect it may always be distinguished from the parent of the Boll Worm, which rests. with the front wings partly open and not entirely covering the hind ones.
The female begins to lay her eggs in from two to four days after issuing from the chrysalis, the time varying with the different generations and according to temperature.
In experiments which we have made with moths confined in vivaria, eggs have sometimes been laid thirty-six hours after issuing, and the moths have continued laying for twenty-one nights, the number laid each night ranging from 4 to 45.
Examination of the ovaries of females at different seasons shows a much greater prolificacy than belongs to most moths, as the number of well-developed ova may reach 500, and of potential ova half as many more. In confinement it is difficult to obtain from one female more than 300 eggs, but that fully double this number are produced in the field during the height of the season there can be little doubt, while the average number may be estimated at about 400.
The natural food of the moth, as we first indicated in the fall of 1878,* is the sweet exudation from the glands upon the mid-rib of the leaf and at the base of each lobe of the involucre of the cotton plant.9 Nevertheless it is attracted to all kinds of sweets, and in most parts of the South it finds a bountiful supply in the exudation from the spikes of Paspalum Itce, a tolerably common grass, but particularly in that copiously secreted by glands at the apex of the peduncle just above the pods of the Cow-pea (Dolichos). In the spring of the year, as Judge Bailey, of Marion, Ala., has observed, it may often be seen in the evening feeding in numbers, first from the blossoms of the Chicasaw plum, and subsequently from those of the peach, Chinese quince, mock orange (Cerasus carolinensis), the early apples, and blackthorn. Later in the season, when the glands above mentioned begin to exude and the tree blossoms are no more, the moths do not seem to be attracted by other nectar-storing flowers, since observations in different Southern States by ourself and assistants have resulted in finding but one species of verbenl (Verbena aubletia L.) frequented, even where both moths and all sorts of
S Alant (Ga.) Constituton September 26, and ScientiZ Anwrien November 15, 1878.






HABITS OF THE MOTH. 11

flowers were abundant. But fruits of all kinds as they ripen are re. orte to, ad figs, apples, pea hes plh apricots, grapes, persimmons, and even melons, are often greatly injured.
Carefully examined, the
tongueisseen to be armed
along its terminal half
with stout and sharp
spines proojecting forward from the upper surface and increasing in
density toward the tip, Fia. 7.--co roNX oT: a, with wings expanded; b, with wings which is beset with them Uo. (Atr Rni'., on all sides. It is by means of this spinous tip of the tongue that the moth works a hole in these fruits, and is thus enabled to ablsor'l the more liquid portions. Apple pomace is especially attractive to them.
We have, in fact, been quite astonished at the perfiating power of the proboscis as exemplified in the puncturing of hard, unripe pears. We have known such to be
punctured quite deeply, the
ffectof the puncture beingfl to
son and disclor the fruit
for some distance around.
The accompanying illustration (Fig. 8), which gives an
enlarged view of the partly
coiled proboscis and a still -P 8 I--noirs OF A lrTIA: a, the coilei promsci, more highly 4 nagiified d e aut lorg dundte. rs;d) b tip of do., more highly
THLr Il n n VIWmd T. Pp11 d.)
of its tip, will explain more clearly than words its adaptation to such puncturing. The stiff and sharp spines are, in fact, admirably suited for rasping and lacerating the pulp and thus setting free its juice. This puncturing habit is possessed by several other moths, and notably by an Australian species (phideres fulonica), which is ery i injurious to oranges, and the structure of the lroboscis of which ha- been well illustrated by Mr. Kiinckel.* A number of our own North American species of Noctuide likewise have the tip of the proboscis more or less spinose, indicating that they also possess the power of extracting juices from other sources than the nectaries of flowers.

TIME ELAPSING FROM ONE GENERATION TO ANOTHER.

This varies according to temperature, and therefore according to season. There is increasing activity and acceleration in development fr the first appearance till July, and thenceforth decreasing activity and retardation in development till frost. Thus in midsummer the w cycle of individual life, from the hatching to procreation, may occupy less than three weeks; while in spring and late autumn it may
Compte Redus (French Academy), August 30, 1875.






12 REPORT 4, UNITED STATES ENTOMOLOGICAL COMMISSION.

occupy twice that time. Taking the whole season through, however, the time from the egg of one generation to that of another will average about one month.10

TIME OF YEAR WHEN THE FIRST WORMS APPEAR.

Until the Cotton Worm investigation was begun, our knowledge as to the earliest appearance of the worms was not only vague, but misleading. The statement emphasized by Mr. Grote in the paper already referred to, namely, that the worm does not appear earlier than the latter part of June in the central portion of the cotton belt of Alabama and Georgia, very fairly echoes the prevailing popular belief on the subject; yet careful investigation shows the statement to be essentially erroneous. The date of earliest appearance varies with location, and largely with the curves of isochimal lines;' it also differs somewhat in different years in the same location, according as the season may be late or early; and, lastly, it may differ to some extent in different parts of the same restricted locality, worms having been found just hatching in one place when, only a few miles distant, others were found nearly full grown.
While these modifying circumstances complicate consideration of the subject, it is easy to arrive at definite results by taking as a basis observations made at a few particular points during the year. Hence we felt the importance of having such observations made during the spring of 1879 in South Texas and South Alabama at those places where the worm was reported to have appeared earliest in past years. As a result, the fact was fully established that the first worms of the season may, and do, in ordinary years, hatch from the middle of April to t he middle of May in the southern portion of the cotton belt. And, moreover, all the facts showed that this season was a late one, for April frosts retarded the starting of cotton in those very sections of Alabama where the worms were first found; while it is the unanimous opinion of planters in South Texas, where the worms were first noticed, that cotton was from two to three weeks later in 1879 than usual. Therefore, when in the spring of 1882 we found the worms of all sizes on rattoon cotton during the latter part of March, in South Georgia and Florida, we were not surprised, although this was fully six weeks earlier than they had ever before been noticed or recorded.2
The first worms are always comparatively few in number and in isolated spots. They are, therefore, easily overlooked by all who do not take particular pains to search for them. From such spots as centers the worms multiply and spread in subsequent generations, with greater or less rapidity, according as the conditions are favorable or otherwise. Such increase and spread may be confined to some part of a given county until the cotton is nearly ruined before the cotton in the rest of the county is affected. The worms will then first appear in the remainder much more suddenly and numerously than they did in the former, the parent moths migrating thereto in bevies. As a rule, however, the spread in the southern portion of the belt is gradual and the worm in






NUMBER OF ANNUAL GENERATIONS. 13

destructive numbers is preceded by one or more scattering generations in the same field.
Other things being equal, the worm minLst appear earliest il the southernmost latitudes, since extended observations on the appearance of other insects show that there is retardation of from four to seven days with each degree of latitude northward. 3
There is, in normal seasons of little injury to the crop, a similar retardation northward in the appearance of the Cotton Worm within the southern portion of the belt, corrTsponling in son sremeas wit ih the growth and development of the plant; and it is a notable fact that the worn is seldom noticed and never in great nlbtiers before the plant hegins to bloom. What is generally under these circumstances calle'l the first brood or "crop" has been preceded by at least one alnd otten two generations sparsely distribut-ed over the iclds. Yet in years when the worm aboumnls to a disastrous extent in the southern Iportion of the belt, it appearance in the northern or temporary portion calot he cou'red on with any certainty as to time, because it is always the result of m11igrations in the winged state, and these migrations may be more or less extended according to circumstances. Bet ween the first al ppelraice of the worm in the southern and northern portions of the helt there is, therefore, a marked difference ordinarily observable, it being in the litter much litter and in far greater nunmb.ers.

NUMBER OF ANNUAL GENERATIONS.

The general impression and belief that prevails in the South is that there are, in those sections where the worm is most injurious, tbrece broods or generations, or, as the planter puts it, "trolls," each year. This statement of the case has also betcn accepted as correct ly uiost previous writers on the subject.," It is, however, essentially err)neltus, so far as the southern portion of the cotton helt is concerned, as t lhe earlier and later generations are not taken i, to accountl but overlooked. The appearance of the first generation Ihas already been tisensci, a, it occurs during the latter part ol' April and in MI y in thle more s)llit hl. portions of the bett, and even in March in Florida. Onc geCerati)on follows another continuously from that time on, just so long as there are ay leaves to be devoured, and we have, by protecting both il it tand insect from frost, kept the moths ovipositing in the city of Washington all through November; while the worms, uIndler like conditions, have watched through the early part of December, matured, andi spun up about Christmas time.
Careful observations and experiments in 1879 in South Texas show that at least seven, and probably even more, annual generations are produced there. The first two generations are generally well separated, but, owing to the irregularity in egg-laying and in individual d(evelopment, the later generations so cross each other, that the insect may be






14 REPORT 4, UNITED STATES ENTOMOLOGICAL COMMISSION.

found in all stages in the same field at one and the same time. Yet the succession of broods may be recognized by the condition of the bulk of the specimens in the field or by confining the insects for the better watching of them.
The first generation, as we have seen, is confined to spots. The second generation is more dispersed, but still restricted to areas in the vicinity of the hibernating centers. The third generation of worms may become, under favoring conditions, not only widespread but disastrous, and the moths produced from them so numerous that they acquire the migrating habit. This generation appears in South Texas during the latter part of June, and in South Alabama and Georgia somewhat later. This is usually the supposed first brood in those sections, i. e., the first which attracts general attention. The subsequent generations naturally become more and more widespread, and the increase during July and August, 1880, was noticeable in the face of meteorological conditions unfavorable thereto. The worms during these months will appear in those fields in which they did not appear earlier, as on sandy, elevated prairies, soils or lands where the growth of the plant was retarded from late planting, overflowing, the injury of the plant-lice, or whatever cause. If the weather be favorable, this August generation will, when unmolested, carry ruin in its wake. Did one generation follow another in the natural ratio of multiplication, such is the fecundity of the species that there would be no hope of profitably cultivating cotton. Fortunately for man, some of the earlier generations are liable to be so effectually kept in check by natural enemies and other adverse influences that they become innocuous and frequently escape notice. This fact was strikingly illustrated in MlIay, 1879, in Colorado and Lavaca Counties, in Texas, where the second generation, which hatched in sufficient numbers in most fields to create alarm, nevertheless vanished before its enemies so completely that it was difficult, a little later, to find a perfect -chrysalis.
That this second generation may exceptionally become very injurious is shown from records, to the effect that in the early part of June of the same year,while the cotton stem was yet tender, whole plantations in the low bottom lands of Louisiana have been eaten to the ground; but that it more often proves harmless is probable for various reasons. The plant-lice, which are apt to be very numerous on the very young cotton, partially disappear before their natural enemies by the time this second brood of worms is developing. The ants, which were previously supplied with food by the plant-lice, have now multiplied, and are forced, by the decrease of the aphides, to seek other food. They are consequently more effectual in destroying the young worms. All the other enemies of the worm are also more active during the month of June, and gregarious birds, like the blackbirds and ricebirds, are very common during that month, but generally leave the fields later.
In the northern portion of the cotton belt the number of annual gen-






MIGRATION OF THE MOTHS-HIBERNATION. 15

rations is, of course, fewer, and will vary according to the date of the icoming of moths from the further south, and according to other circumstances. The generations are not only fewer, therefore, but more easily separated and defined.

MIGRATIONS.
Many persons, noting the short and clumsy though rapid and (arting flight of the moth, when disturbed during the day-time, get the idea that it is incapable of extended flight. But it has great power of wing, and its migrating habits are abundantly attested. It has been observed in numbers, far out at sea, and captured in autumn off the coast of New England, around Chicago and around Buffalo--the species being identified by competent entomolog-ists like Packard, Burgess, Grote, and Westcott. We have known it to do considerable injury during September to peaches in Kansas, and to ruin acres of cantelopes during the same month as far north as Racine, Wis. That it is aided in these distant flights by favoring winds there can be no doubt, but that it does not depend on them for dispersion is equally certain. A factor to be considered, also, in connection with these northern appearances, is the probable existence of one or more northern food-plants.
Dr. D. L. Phares records the destruction, by the worms, of cotton the first year planted, eighty miles from any point where cotton had been grown before; while Mr. 1I. P. Bee (see letter in Appendix) shows that they appeared in Mexico on cotton planted two hundred miles from any other fields. Numerous similar cases might be mentioned.
The migrating habit is common to many insects and other animals, but is almost always associated with excessive multiplication. Such is likewise the case with Aletia, as the observations of past years have clearly shown. So long as the worms are not numerous enough to materially riddle the cotton, the moths produced from them busy themselves with ovipositing in the neighborhood where they were born, spreading only comparatively short distances on all sides; but whenever the cotton is well "ragged," then the moths acquire the migrating habit and appear in numbers everywhere-in town and village, and at lights far away from cotton-fields. The time of year when this migrating habit is acquired varies, but it is rarely till after the third generation of worms, or the latter part of June and fore part of July in South Texas; while it is most pronounced during the autumn months. At such times the moths may be noticed, during cloudy days, starting off by rapid flight and ascending high in the air till lost to sight; and the contrast between this movement and the darting and hiding of the normal day-flight is quite striking to any one who has witnessed it.
HIBERNATION.
No question connected with the Cotton Worm has given rise to more speculation than that of the hibernation of the insect, and this fact at once finds its explanation in the difficulty that surrounds the subject.






16 REPORT 4, UNITED STATES ENTOMOLOGICAL COMMISSION.

As partly illustrating this difficulty it will be well to elaborate the statements made in a paper read by the writer before the National Academy of Science at its meeting in Washington in the spring of 1879.
There are three principal theories on the subject that are worthy of consideration, and that are held by those with whom we have come in contact, or with whom we have corresponded. These are:
1st. That it hibernates in the chrysalis state.
2d. That it hibernates as a moth.
3d. That it does not hibernate in any part of our cotton-growing States, but comes into them on the wing from warmer climates where the cotton-plant is perennial.
Some few persons think that it winters in the egg state in cottonseed or on the dead stalk of the plant; but such views may be disposed of by the statement that they are unsupported by even the appearance of fact.
At first blush it would seem easy enough to dispel whichever of these theories is erroneous and settle the question under consideration by a few simple facts of observation. The trouble is, however, to get at the facts.
About one-fourth of the intelligent people of the South hold the opinion that this Aletia hibernates in the chrysalis state, some believing that it does so above ground, others that it retreats beneath the surface of the ground. It has generally been stated by the writers on this insect that the chrysalis couhl not endure the slightest frost. We have been able to prove that it will suffer with impunity a temperature of from five to ten degrees below the freezing point, but that it cannot withstand a lower temperature; and all those chrysalides which do not give out the moth before severe cold weather sets in perish beyond any doubt. How easily men are misled even on this point,- however, may be gathered from the fact that Dr. Anderson kept what he believed to be living specimens until after the severe cold of December. A careful examination proved that the lifelike motions of such chrysalides were due to the living pupa which they contained of one of the parasites (Pimpla conquisitor) presently to be described. The larger proportion of chrysalides that are not empty after a severe frost has occurred are infested with some kind of parasite, though many of them have perished from the effects of the frost and are either rotten or moldy.
Any number of intelligent planters insist that they plow up the chrysalides in spring, and the belief that the last brood works beneath the ground, out of reach of frost, is very firmly held by some of the most experienced cotton growers; but in every instance that has come to our knowledge the chrysalides thus plowed up have proved to belong to other species, most of them of the same family, and many of them having a sufficiently close resemblance to those of Aletia to confound any but the most skilled and experienced entomologist. As an illustration of the ease with which erroneous conclusions can be drawn






THE QUESTION OF HIBERNATION. 17

from mistaken identity, we will here quote part of a letter received from Professor Willet, who has particularly interested himself in this subject. "I have received to-night," writes Professor Willet, "from Rev. Robert Harris, of Cairo, Thomas Counity, Georgia, a small tin box inclosing 25 chrysalides, which I forward you by anil. Mr. Harris is an ardent believer in the subterranean hibernation of the chrysalis of Aletia argillaca. I transcribe the portion of his letter pertinent to the

CAIRO, GA., February 22, 1879.
'Washington's birthday and victory. Pcrxererantia rincit. The facts drive "analogy" to the wall. Here they are: 25 cotton-worm chrysalides ploughed up out of the ground in a field that was riddled by the insects last tall.
'This is unimpeachable evidence, and in the opinion of the court is amply sufficient to convict the prisoner.'

"The chrysalides," continues Professor Willet, "appear to my eye very like Aletia chrysalides which I have in spirits, and I await your verdict with interest."
The chrysalides referred to in this instance resemble those of Aletia so thoroughly in form, size, and general appearance that they might have been mistaken therefore even by some entomologists; yet, from certain minute structural differences. easily observable with a good lens, we were able at once to decide that they belonged to another insect, the Aspila virescns#of Fbricius, aleautiful moth, with olivaceous primaries, marked with three distinct, pale, transverse lines, relieved by coincident deeper shades, the translucent green larva of which, speckled with minute, pale, fleshy elevations, we have found feeding on Solanum s eglinge in Saint Louis.16
There are many species of night-flying moths which go through their transformations beneath the ground, and there hibernate in the chrysalis state. The leaves of the cotton-plant are palatable to a very large number of such, while the Boll-worm (Heliothis armigera) and the "Grassworm" (Laphagma frugiperda), which thus transform, are sometimes very abundant in a cotton-field. It is not at all surprising, therefore, that the chrysalides should be plowed or dug up in land planted to cotton. All of them, upon careful scrutiny, will be found to differ from the chrysalis of Aletia, which may be distinguished by its slender form, and particularly by the tip of the body with its armature, as shown in Fig. 4. In short, the nature of the Aletia chrysalis effectually prevents it from working beneath the ground, except where, dropping out of its cocoon, it happens to fall into some crack or crevice, and thus wriggle beneath the surface. It is also contrary to all analogy that a chrysalis normally found above ground in a cocoon should work beneath the soil; for all insects that pupate under ground descend while in the larva state.
Experiments which we have repeatedly made prove that the Aletia chrysalis, when placed under ground, either rots and perishes or the
63 coNG-2






18 REPORT 4, UNITED STATES ENTOMOLOGICAL COMMISSION.

moth, if in a sufficiently advanced state when the chrysalis is buried, will vainly attempt to escape and push through its unnatural surroundings
Regarding the ability of the moth to survive the winter, nearly onehalf of the more intelligent correspondents state that they have known the moth to be found flying during warm days in the winter, and that it consequently hibernates in that state. Mr. John T. Humphreys, of Morganton, N. C., who was for a while employed by the State of Georgia in entomological work, says that he has absolute proof of the hibernation of the moth.
Page after page of testimony and experience from the most competent and reliable planters might be adduced in support of the fact that the moth is to be seen either hidden in sheltered situations or flying during the milder weather of winter and in spring, in all of the southern portion of the belt. The situations in which it is most often reported as sheltering are under the shingles of gin-houses, under rails, and under the loose bark and in the hollows of trees and prostrate logs. In old pine stumps the sapwood separates from the heart-wood and forms excellent retreats for this purpose. The general hue of the large scales of pine bark is sufficiently close to that of the moth to make the resemblance protective. A dense forest of long-leaved pines also modifies and equalizes the winter temperature. These facts would lead one to suppose that pine forests offer unusually favorable conditions for hibernation, and Mir. Humphreys has, in fact, found the moth hibernating under pine scales, while some of our most reliable correspondents report having seen the moths sporting in great numbers in the edges of pine forests during the month of March.
Nevertheless, the persistent search by Mr. Schwarz in the winter of 1878-'791", under our direction, failed to reveal the moth under pine bark; whereby we were led to the conclusion that it seeks winter shelter some distance from the ground. It has been reported by some correspondents in greatest numbers in swamps of sweet gum, oak, magnolia, poplar, &c., such as are found in southern Alabama. These swamps are warm, moist, and miasmatic, and the moths are said to have been seen literally packed together in a torpid state in the hollows and burrows made in rotting logs by boring larvae.
The evidence on this point of the hibernation of the moth would be overwhelming did it come from scientific observers; but, unfortunately, allied species are so often and so ea-ily mistaken for Aletia that doubt still surrounds the subject. The liability to confound hibernating species is all the greater in that characteristic markings are more or less effaced or faded. The IHypena scabralis (Fabr.),8 a moth belonging to a different group (Deltoids), and which hibernates in the imago state all over the country, is especially common in the Southern States, and large numbers have been sent to us as the genuine Aletia. It is nearly of the same size and form, and while normally of a darker brown, faded hibernating specimens are easily mistaken for the Cotton Moth because






THE QUESTION OF HIBERNATION. 19

of undulating darker lines across the front wings, somewhat similar to those on the latter. Its palpi are longer and snout-like, and its front wings invariably lack the dark discal spot and the white specks char. acteristic of Aletia.
Phberia atomaris Iliibl., and many other similar moths, have been forwarded with the remark that they were the Cotton Moth; while Leucania unipuncta Haw,, the parent of the Northern Army Worm, which feeds only on
grade s an1111d cereals, is everywhere found in the South during winter, o n account
of its great simillarity in color e to Ah'tia, and of a white dis- c
cl spot relieved Iit a dark Fl;. A-A IMY WO :M MOTH: a, male moth; b, abdomen shade on e1 fie front w iN that of fa i.tl -natmal siZe: e, eye; d, base of male attr Tia; heightens the gelCral tr-e- a$ of female aatena-nlarged. (After Riley.) blanee, is more often mi taken therefor than any other. It is more robust tha i Aletia, an d a colni parish of the accompanying illustration (Fig. 8) with Fig. 7, p. 11, will show the other differences. Seeing how easi non entomologists are 111isled by general resemllaltnces, we would again lay stress on the readily observed characters underlined on page 9, by which Aletia may always be recognized. Where they are absent it may be safely taken for granted that other species are in question. From this danger of confounding species it is evident that ordinary reports lose, when unaccomnpaltied by specimens, much of their value, and must always be taken cum grano salis.
Yet, after making due allowance for possible error, the number of intelligent planters with whom we have conversed, and who, having long and thorough acquaintance with the moth, feel positive of their ability to distinguish it and of having seen it during the winter, is so great as to leave little doubt of the fact; while the added testimony of Mr. Grote, who is such an authority on moths that he could not thus confound species, and who states that he has found the Aletia in Alabama during mild winter weather, should dispel even that little doubt; and we nmay safely consider as proven that the moth does survive the winter up to the end of March. The general experience of correspondents is, however, that after March these hibernating moths are no longer to be seen, and no one knows what bveomes of them between this time and the appearance of the first worms.
The difficulty felt in bridging this gap, together with the progress of injury from the south northward, has given rise to the theory that the species cannot survive the winter in this country, and must necessarily come each year on the wing from some foreign country where cotton is perennial. The history of the repeated suggestions of this so-called migration theory, from Dr. Gorham's first article in 1847, down to






20 REPORT 4, UNITED STATES ENTOMOLOGICAL COMMISSION.

Grote's paper before the American Association for the Advancement of Science, in 1874, we shall give somewhat in detail in Chapter XIV, but in this connection we may appropriately devote a brief space to the consideration of Mr. Grote's arguments:20
The principal arguments urged in support of the theory by Mr. Grote are [1] the sudden appearance of the moth in quantities; [2] the first appearance of the worms so late as the latter part of June; [3] the absence of parasitic checks; [4] the highly probable exotic origin of the species and its introduction into the States; and [5] the power of flight and migratory habits of the moth. The first three lose much of their force from the facts adduced in this report, since [1] in the southern portion of the belt21 the sudden appearance is more apparent than real; [2] the worms appear in April;* and [3] they have numerous parasitic checks. There is also little force in the fact of original introduction from some foreign country, since most of our worst insect pests that are now acclimated and established with us were originally introduced from abroad; while [5] the migratory habit, as we have seen, is not developed in the first moths. Arguments urged by others in favor of the theory are [6] the periodical visitations and intervals of immunity; [7] the short life of the moth; and [8] the failure of those who have tried to keep it through the winter.
To these it may be replied that [6] many other indigenous insects abound during certain years and are unknown in others, and that these changes are due to the working of well-known laws; that periodicity in the appearance of Aletia is largely imaginary, because it either refers only to bad years and takes no stock of small numbers, or else is local. The investigations of the Commission show that the worm has been in some parts of the South ever since the civil war, and there is no reason to suppose that it was not annually to be found in fewer or larger numbers prior thereto. [7] The short life of the moth of the summer generations is no criterion for that of the last or hibernating brood, since any num. ber of species which produce several annual generations and have but a brief span of life in the imago state in summer are known to hibernate in this state. [8] Itis extremely difficult to attain, in a room, the proper conditions of moisture and freshness that belong to a sylvan atmosphere, and we have never been able to keep other Lepidoptera which hibernate in the imago state alive through the whole winter in such artificial situation, though we have tried with both Danais archippus and Paphia glycerium. For this reason it will always be next to impossible to get absolute and incontrovertible proof of the hibernation of Aletia by watching the moths from fall till they oviposit in the following year, but it may be truly said that if the hibernation of other species rested on equally absolute proof, there is not one among the Lepidoptera, or other Orders, for that matter, that could be said to hibernate. One other argument that has been made in favor of the theory may lastly be mentioned. It is that during the late war no cotton was grown for three years in some sections of the
See further fats in Note 12.






THE QUESTION OF HIBERNATION. 21

South, and that the first crop raised thereafter was infested. Professor Constock took particular pains to make inquiries on this head, and found that some patches of cotton had been grown every year in such sections.
In favor of hibernation in the southern portion of the cotton belt may be urged [1] the appearance of the moth on the wing during mild winter weather, and its being found torpid in sheltered situations, as is insisted on by so many; [2] the first aIpearance of the worms in very small numbers, and in the spring of the year, as attested by recent observations; [3] their reappearance each year in the same spots, not on the sea-coast nearest to the tropcal zone, where wve should expect them on the theory of annual incoming, but at various points far inland; [4] the coming of the moths in large nit ibers and as immigrants into the northern portions of the belt, being always prdeceed by the appearance of the worms and their gradual increase at soine other, generally more southern or western, points; .and [5] the decrease of cotton culture in Central Armerica and the West Indies, as appears from market statistics, and the absolute absence of the worm in the Bahamas since 18ti6, as ascertained by 'Mr. Schwarz while there in the spring of 1879.
The strongest fact against hibernation was, perhaps, the period laps. ing between the disappearance of the moths in March and the first appearance of the worms, or, to putt it in another form, the absence of thle woris on the young and tender cotton. The period during which the species was not observed is already reduced by the facts given in this report to less than one month instead of three, and this is much less than the time elapsing between the issuing from winter quarters of other well-known Lepidoptera that hibernate in the iimago state, and the first appearance of their larve, numerous illustrations of which fct might be cited.
On he whole, therefore, the weight of evidence is strongly against the theory of annual extermination, in the southern part of the belt, and the fact of the hibernation of Aletia there may be said to rest on as good evidence as that of many other species in which it is admitted without question. Yet Aletia is beyond doubt killed out each winter in the northern portion of the cotton belt, and all the arguments in fitvor of annual extinction and icoinoming de noro have force when restricted to this section. Just where the separating line lies between extinction and survival is not so easy to decide, and for the present we can only refer to that given in the Introduction as the result of the investigation so far as it has gone. This conclusion that the moth does and can hibernate in the United States does not preclude its occasional incoming from foreign, more tropical countries, or the possibility of its being brought by favorable winds from such exterior regions, just as originally must have been the e when the species was first introduced. The facts indicate, however, that this kind of immigration is less frequent now-adays than it was in the beginning of the century.
The ntervening period is still frther lessened, as will be sen from the remarks on page 12 and in Note 12.






22 REPORT 4, UNITED STATES ENTOMOLOGICAL COMMISSION.

To sum up the evidence from present knowledge: Aletia never hibernates in either of the first three states of egg, larva, or chrysalis, and it survives the winter in the moth or imago state only in the southern portion of the cotton belt. Our own investigations since 1878 in every cotton-growing State in the Union, together with the experience and testimony of both correspondents and special agents employed in the investigation, confirmed us in these conclusions, and we were consequently perfectly prepared for their justification by the ficts obtained during the winter of 1881-'82. During this winter we were able to obtain the moths during every month, and watched them in fact until the early part of March. In short, there is nothing more fully established now than that the moth hibernates principally under the shelter of rank wire-grass in the more heavily timbered portions of the South, and that these moths begin laying on the rattoon cotton when this is only one inch or so high.*
1. It is quite certain that by far the larger portion of the moths from the last brood of worms perish in various ways without perpetuating the species. All those which fly north of the cotton belt must needs thus perish, as doubtless do all those that attempt to hibernate in the northern portion of said belt. The evidence is strong that even in the hibernating portion of the belt only the exceptional few, more favored than the rest and remaining steadily torpid till early spring, survive to beget progeny. Those which are aroused to activity during the mild winter weather spend their force without finding compensating nourishment, as there are neither fruits, flowers, nor sweet-secreting glands at that season wherewith to break their long fast and sustain vitality. It is for these reasons that the worms are generally less injurious after mild and changeable winters, and most to be dreaded after severe and steady ones, and it may very justly be argued, that did the larger proportion of the moths survive, there would be no chance to grow cotton. Like perishing of the bulk of most insects that hibernate above ground is, in fact, an acknowledged rule inentomology.
2. The localities where Aletia doubtless hibernates, and where, consequently, the earliest worms appear, seem. to be more comlnion in the western parts of the cotton belt than in the Atlantic States. Since the civil war the almost complete aban(lonment of cotton cultivation on the sea islands of the coast of Florida and Georgia has evidently redluctd the number of favorable hibernating localities there, and in so far protected the more northern or western i)ortion of the Atlantic States from the immigration of the moth from those quarters. In Texas, on the con. trary, the cultivation of cotton has been constantly increasing since that time, and consectaneously tlh( number of hibernating points and the risk of serious harm there over extended areas have also increased.
See abstract of paper read before the National Academy of Sciences at Washington, May, 18L82 also Annual IoReport, Department of Agriculture, 1881-'82, p. 166.











CHAPTER III.



PAST HISTORY OF TIE COTTON WORM IN THE UNITED STATES.

C~IIONOLOGICAL ACCOUNT OF APPEARANCES AND OF YEARS OF MARKED PREVALENCE.
We have been unable to find any record of the appearance of the Cotton Worm in the United States prior to the oft-quoted statement of Spalding's,* that in 1793 "the destruction was complete. In Major Butler's field of 400 acres but 18 bags were made." From this time till 1800 no mention has been made of the worm; but in that year the crops in South Carolina and Ge(orgia suffered severely. Dr. Capers,t and also Dr. Pharesj give 1800 as the first appearance of the worm in South Carolina; but there is a published statement of Mr. J. NW. Grace j to the effect that the Georgia invasion of 1793 extended to that State.
1804 was a marked year, and we always find it referred to in the older papers on the worm. Iu this yeir the Gulf States suffered for the first time. Louisiana, which grew more cotton than any other State, suffered severely. The crops on many plantations were entirely destroyed; but the caterpillars were finally killed by an unusual snow-storm.
From this time to 1814 we have found no definite record of the caterpillar, bat 1814 was again a year of serious loss in Louisiana, although it does not appear to have been marked upon the Atlantic coast. In this year the rather remarkable instance is seen of the almost total destruction of the crop as early as June. 11
1825 was again a year of general loss from the worms. The destruction was likened to that of 1804, and was universal throughout the whole cotton belt. Concerning this year we may quote from Dr. Phares:
In 1i5 the destruction was general in extent, embracing all the Cotton States; the late Mr. Affieck in one of his papers asserting that the destruction was "universal and complete" I must here be permitted to say that it was not "complete," as I most distinctly remember and know I saw tields in which many bolls were fully niatured and gathered before the chenilles injured the plant, and considerable quantities of very superior cotton were made. This was the first year that I saw the chenilles, and circumstances so impressed me that my recollections of their appearance are more vivid than of any time since.
*See Farmer's & Planter's Cyclopedia, London, 1843: Article, Cotton. t Botsern Arictrist, 1828, p. 203 (VoL I).
Rural Carolinian, August, 1870.
SReport upon Cotton Insects, 187 9, Department of Agriculture, p. 387.
SSee DeBow's Review, 1847, p. 251 (P.Winfree), and Dr. Phares in Rural Carolinian, August, 1870.
23






24 REPORT 4, UNITED STATES ENTOMOLOGICAL COMMISSION.

The insect was again destroyed by a storm, as we have seen happen less extensively several times since; the wind and rain beating them down, and the water sweeping them along and forming immense heaps in some places.
In 1826 the destruction is said by Dr. Capers to have been again universal, although other testimony to this fact is lacking. In limited localities the worms were noted in 1828, 729, '30, '31, '327 '33, 34, '35, and '36. Considerable damage was occasionally done, but it was by no means general again until 1838, the worms that year spreading over nearly the, whole belt and doing especial damage in Florida and Southern Georgia.
In 1834 the worms appeared for the first time in Texas, and in 1840 in Arkansas. This last year was one of quite general injury to the crop, northern Florida suffering particularly. In 1841 Florida again suffered, as also in 1843. In 1844 the marked feature was the severe damage in central and southern Louisiana. In this State there was a shortage of nearly 50 per cent. of the crop on account of the damage done by the caterpillars. In Mississippi and Alabama some little damage was done the same year; but in Florida, Georgia, and South Carolina the loss was almost nominal.
In 1845 the damage was again considerable in Louisiana, and the other States suffered as well, the total loss from caterpillars being greater than in any other year since 1838.
1840, however, overshadowed, perhaps, all previous cotton-worm years. The caterpillars appeared in force much earlier than they had ever been seen before, and from Texas to South Carolina hardly a plantation escaped without loss. In South Carolina old inhabitants say that the ruin of the crop was complete. In Florida more than half the total crop was lost. In Alabama the loss was nearly as great. In Mississippi and Louisiana on a general average one-third of the crop was destroyed. Writing to the American Agriculturist September 9, 1846, from Washington, Miss., Mr. Thos. Alieck gives the following graphic account of the situation:
The Caterpillar, Cotton Worm, Cotton Moth (Yoetua xylina), or chenille of the French West Indies, Guiana, &c., has utterly blighted the hopes of the cotton-planter for the present year, and produced most anxious fears for the future. I have heard from the greater part of the cotton-growing region-the news is all alike-the worm has destroyed the crop. I have no idea that any considerable portion of any State will escape. * The present year the crop is unusually backward, at least four weeks later than usual. We have but just commenced picking; usually beginning about the last week in July or the first week in August. At this moment every field within this region of country, say south of Vicksburg, is stripped of everything but the stems, the larger branches, and a few of the first bolls, already too hard for the worms' power of mastication. The full-grown bolls not yet become hard are completely eaten out, a circumstance I have never heard of but once before, in 125. The fields present a most melancholy appearance; looking from the bluff at Natchez across the river to those fine plantations back of Vidalia, nothing is to be seen but the brown withered skeleton of the plant.






CHRONOLOGICAL ACCOUNT OF COTTON WORM INJURY. 25

n Texas the coast counties were overrun, but the inland counties, with here and there a marked exception (Walker lost 50 per cent. of the crop), escaped without particular damage.
It was at the close of this year that the theory of periodical recurrence of the worms in destructive numbers every twenty-one years begn to be mentioned in the newspapers. Some person, noticing that the years of great disaster, 1804, 1823, and IS46, were separated by periods of twenty-one years, formulated the ththeory that these periods were constant, and that in 1867 another similar invasion was to be ex.pected. The contid(ence with which this idea was universally regarded warrants its its mention here.
In 1,47 the months of June and July augured an exceedingly bad worm year, for the caterpillars appeared very early in considerable force and were widespread. The season, however, proved unfavorable to their great increase, since it was remarkable for periods of great heat and drought, interrupted by an occasional severe storm, and coinparatively little damage was done by the caterpillars, although the crop suffered from the other causes mentioned.
From this period to 1T66 there was, as far as we can ascertain, not a single general caterpillar year. The worms were every year to be found, and occasionally did some severe local damage. Thus in 18$4, 1831, and 1852 the crops of northern Florida were injured quite seriously; 182, 18, and 1860 were quite marked in the canebrake region. In 1&33, 18 0, and 1864 the worms were more than usually injurious in Mississippi and Louisiana. In 1830 they made their first recorded appearance in Tennessee. 184 and 1865 were marked by the appearance of the worms in North Carolina. The visitation in both of these years seems to have been severer than in any year since 1847, though it is difficult to compare them on account of the comparatively small amount of cotton grown during the war.
From 1866 up the present date the worms have been widespread every year. It is a common thing to hear planters say, "The worm never used to be as destructive as this before the war"; and indeed the records seem to bear out the assertion. We may look for the reason, without doubt, in the general looseness and carelessness of the system of cultivation since, as compared with the clean and thorough methods before the war.
A large crop in 1866 was a necessity. Cotton had risen greatly in ilue, and as a consequence of this and of the liberation of the planters from martial occupation the acreage was largely increased over the preceding five years. Unfortunately, however, it proved a bad worm year. The losses may be averaged about as follows: Louisiana, Texas, and Alabama about 40 per cent.; Mississippi, 30 per cent.; Georgia, Florida, and South Carolina much less. The hopes and fears for the result of this crop and the disastrous effects of the advent of the worms am well told by rs. Harriet Beecher Stowe in an article entitled "Our






26 REPORT 4, UNITED STATES ENTOMOLOGICAL COMMISSION.

Florida Plantation" (Atlantic Monthly, May 1879, p. 641). The worms were this year very destructive in southern Arkansas, and also did some damage in North Carolina.
There were not lacking those who, on the coming of 1867, prophesied a year of general devastation on account of the space-21 years-be-i tween this year and 1846; but, contrary to their expectations, 1867 was but little worse than 1866. Texas, it is true, suffered severely, but the other States were comparatively exempt. The districts along the Mississippi River in Louisiana, Arkansas, and Mississippi were damaged considerably, but the interior counties were injured but little. In Ala-. bama, Georgia, and Florida the total losses were slight. Here and there the crop of a small district.would be taken, but the average loss was low. In the latter part of the season the worms were numerous in South and North Carolina, but they injured the crop but little.
1868 proved to be one of the most disastrous years on record. The worms appeared in May in Texas, and the gravest fears were expressed from this early advent. On the whole, the loss in Texas and Louisiana did not equal that of the previous year. In Mississippi the loss was rather greater than in 1867. Alabama and Georgia suffered exceedingly; the loss in the latter State was entirely unprecedented. Through the central part of the State the average loss is reported at 50 per cent. In Alabama, with a few exceptions, the central and northernmost counties were damaged the most, the exceptions being Conecuh, Crenshaw, Barbour, and Montgomery. In South Carolina the crops were injured in some localities to the extent of a loss of 33 per cent. In North Carolina, though numerous, the worms were not destructive, clearing away the leaves just in time to assist in the ripening of the oolls.
One cannot help but notice, in studying these appearances of the worm from year to year, that they come in waves, gradually increasing, until at length, from one cause or another, they break. and almost disappear. 1825, 1846, 1868, and, as we shall see, 1873, 1876, and 1881, are the culminating points of such waves or series of years during which the ravages of the worms have been gradually increasing, and in the year following each of these comes the breaking, and the next wave is begun. With a few unimportant exceptions, this rule is observed throughout the entire history of the Cotton Worm.
This result is natural, and arises from the tendency of the worms to increase in geometrical proportion and at a more rapid rate than their parasites. But whenever they have multiplied beyond the power of their food-plant to sustain them, or whenever meteorological conditions unfavorable to their increase obtain, the parasites get the upper hand and the break in the series occurs. This rise and fil has often been noticed by writers on injurious insects, but from the very nature of the case it is not regular, and cannot be depended upon.
1869 proved to be a year of drought, and there was a sudden decrease in the loss from the caterpillars. Here and there the crop of a county






CHRONOLOGICAL ACCOUNT OF COTTON WORM INJURY. 27

was taken, but the loss was by no means general. In "Wayne County, orth Carolina, ge to say, the worms came in August and injured the crop to a slight extent. South Carolina suffered no loss. In Georgia, the southern tier and the coast counties were damaged quite badly, but the remainder of the State escaped.
Of the northern counties in Florida, Bradford, Leon, and Putnam sustained quite severe losses, while Santa Rosa, Jackson, and Dural suffered none. In Alabama considerable damage was ldone to a few counties, as Wilcox, Macon, Dallas, and Greene. In Mississippi and Louisiana, the loss was insignificant. .In Polk, Blanco, Matagorda and Goliad Counties, Texas, the cotton was badly eaten, but the remainder of the'State was comparatively exempt.
The worms, instead of increasing in numbers in 1870, as should have been the case according to the rule just mentioned, were decidedly fewer and less destructive than in 1809, the same causes operating to produce this result, as 1870 proved to be a year of severe and long-continued drought. In North Carolina, South Carolina, Georgia, Florida, Alabama, and Mississippi the worms were found, but almost no damage resulted. Isolated counties in Texas suffered, while in Louisiana by far the greatest damage of the year was done. Rapides, Avoyelles, East Feliciana, Tensas, and Jacksoan Parishes each sustaned a loss of from 5 to 20 per cent.
In 1871 the increase again commenced, the principal damage, as in the previous year, being done in Louisiana. N orth and South Carolina sustained no loss, and Georgia suffered but slightly. In Florida the crop was so severely injured by heavy storms that the worms were hardly noticed. In Alabama and Mississippi there was a decided increase in the number of worms. In Louisiana the crop as a whole was very badly damaged, though in many parishes the loss was slight. The distribution of the points of heaviest injury was strange and dlifficult to explain. Great loss was sustained in Iberia, Saint Landry, Washing. ton, Avoyelles, and Caddo; less in East and West Feliciana, MRaides, and Richland; while in Tangipahoa, Madison, Tensas, Red Iiver, Claiborne, Ouachita, and Morehouse but few worms were to be found. In Texas the worms were widely distributed, but in only a few counties was even the top crop (representing 5 per cent. or a little more) taken. In Lafayette County, Arkansas, the late-appearing caterpillars damaged the crop to some extent.
In 1872 occurred another and greater increase in the damage done by the worms. In fact, the loss this year was so great that 1872 is entitled to be ranked as one of the years of general loss by the side of 1804, 1825 1846, 1868 and 1873, although considerably inferior to the last-named and possibly to the early ones. The caterpillars appeared early in June in Florida, Louisiana, and Texas. In Texas the amount of damage was not great. In Louisiana it fully equaled that of the previous year. Tangipahoa, Marion, Concordia, Rapides, Saint Landry,






28 REPORT, 4, UNITED STATES ENTOMOLOGICAL COMMISSION.

Washington, Red River, and Jackson Parishes all sustained great loss. In Mississippi many of the central and southern counties were devastated, the more northern part of the State enjoying comparative immunity. We quote from the Monthly Report of the Department of Agriculture for September, 1872, as to the state of affairs in Alabama: Our August returns from Alabama foreshadoweil an extensive visitation of the cotton caterpillar, which, as our September reports show, was fully and painfully realized. In some places the boll-worm vied with the cotton-worm in its destructive influence. Reports of either or both of those pests come from Macon, Pike, Marengo, Conecuh, Perry, Montgomery, Crenshaw, Russell, Fisk, Calhoun, Chambers, Butler, Autanga, Dallas, Wilcox, and Tuscaloosa Cotnties. In Crenshaw the fields were denuded of foliage. In Calhoun the crop prospect was reduced 25 per cent. in fiye days. In Autauga the roads, woods, and wells were full of army and boll worms. In Wilcox the caterpillars, after stripping the cotton-plant of its leaves, attacked the bolls, eating the smaller ones and killing the larger ones by gnawing around them. In Perry the crop was cut down to half an average after August 20. In Conecuh the destruction was almost complete, as it also was in Russell. All through the cane-brake region the loss was very severe. Butler, Clark, Wilcox, Dallas, Perry, and Tuscaloosa report a loss of one-half; Pike, Bibb, Hale, Calhoun, and Limestone a loss of one-fourth or Over.
In Florida also the loss was very great; Suwannee, Leon, Taylor, Columbia, Orange, Jackson, and Jefferson Counties all lost from 50 to 75 per cent. of their crops, while Clay County lost 33 per cent. Nearly every cotton-growing county in Georgia and South Carolina was visited sooner or later, but the losses were not great compared with those of Florida and Alabama. The worms were also remarkably widespread and abundant in North Carolina, although not particularly injurious. They also appeared in southern Arkansas.
In the whole history of the Cotton Worm in the United States, from 1793 down to the present time, it is doubtful whether 1873 was ever equalled (certainly never exceeded) in the loss occasioned by worms. Throughout the whole extent of the cotton belt hardly a plantation escaped, and in many cases the crop was a total loss. In many localities the caterpillar made its appearance for the first time, and has not since been reported. There must have been a very extensive hibernation of the moths, for as early as the latter part of May the worms had appeared in sufficient numbers to be reported from Florida, southern Georgia, Alabama, Mississippi, and Texas. The appearance of the destructive brood at the end of June was extensively reported, and the localities are of great interest as bearing upon the subject of centers of hibernation. They are as follows: Decatur County, Georgia; Liberty, Leon, Jackson, Gadsdei, Suwannee, and Columbia Counties, Florida ; Clarke, Wilcox, Dallas, Tuscaloosa, Barbour, and Saint Clair Counties, Alabama; Wilkinson, M arion and Jasper Counties, Mississippi; Tangipahoa, West Feliciana, Concordia, Ralides, and Carroll Parishes, Louisiana; and Atascosa, A ustin and Galveston Counties, Texas.
It will be unnecessary to go through the list of States specifying






CHRONOLOGICAL ACCOUNT OF COTTON WORM INJURY. 29

which counties suffered the most. In Louisiana, Mississippi, Alabama, Georia and Florida the greatest damage was done. Texas did not suffer so much proportionately, although it experienced a great loss. In Arkansas, South and North Carolina more damage was done than had ever before been known; while in Tennessee and even in Virginia the worms were found in great numbers towards the close of the season.
The following extract from the Monthly Report of the Department of Agriculture for February, 1874, shows well the relative causes of injury to the crop of 1873, and the piminence which should be given to the caterpillar:
The relative influence of each cause in damaging the crop of 1873, as indicated by our correspondents, may be stated in the following order in the different States: Korth Carolina.-Rains, frost, worms.
South Carolina.-Rains, frost, worms.
Georgia.-Wornis, more than all other causes combined; rains, frost, drought, high winds.
Floerida.-Storms of rain, worms.
Alahama.-Wormns, rains, frost.
Mi pp.-Worm, spring rains, drought, frost. Louisiana. -Worms, rains, high winds.
Terax.-Wor s, rains, droug(t, frost, bad gins and inexperienced ginners. Arkansax.-Rains, worms, drought, frost.
Tenineae.-Drouight, frost, rains, plant-lice, a cold and wet spring. In the Gulf Stats the greatest injury thus appears to have been wrought by worms, excepting only Florida, where the devastating storms in September and October, particularly that of September 19, proved more destructive than the caterpillar, which was abundant and sulficiutly inJurious.
The prevalence of rains will be noticed throughout the whole cotton belt in the above extract, and should be borne in mind as bearing upon the influence of rain and drought upon the abundance of the caterpillar; 1874, the succeeding year, will be seen to have been very dry and the worms were comparatively innoxious.
In 1874 the worms appeared rather early, but owing to the severe and long- cotinued drought did but little damage except in a few limited localities. The crop was poor, but this was entirely owing to the protracted dry spell. As one correspondent of the Department aptly expressed it, "the drought killed the cotton, and the wol ms too." Appearing in early June in noticeable numbers in Texas, Louisiana, and the other Gulf States, the increase in numbers was remarkably slow until it was too late for the crop to be greatly damaged. In some counties, notably Beaufort and Richland, South Carolina; Murray, Georgia; Lowndes and Wilkinson, Mississippi ; and urnet and Hardin, Texas, the leaves were well tripd, were well stril)ed, which served to render the plant more susceptible to the drought. Altogether 1874 may be considered a year of remarkable immunity.
The growing season of 1875 up to the month of August was also dry, while that month was marked by heavy storms. Both these causes






30 REPORT. 4, UNITED STATES ENTOMOLOGICAL COMMISSION.

operated to still further reduce the numbers of the worms; hence, 1875 is to be ranked as a year of even greater immunity than 1874. The worms were not noticed at all early in the season, and in the few localities where they did inijure the crop, their late coming was all the more unexpected and seemingly disastrous. These localities were confined almost entirely to northern Florida, although some damage was reported from Austin and Polk Counties, Texas; Lowndes County, Alabama, and a few other counties. 1875 ranks as a good cotton year, the general average, according to the monthly statistical reports, slightly exceeding 100, the unit of comparison being normal growth and unimpaired vitality.
During the earlier part of the season of 1876 rains were very abundant over the larger part of the cotton-belt. Later, in September and October, the crop suffered from drought in Louisiana and parts of Texas, but in general the wet weather continued throughout the season. In consequence of this disposition of the weather in their favor, there was a most marked increase in the number of the caterpillars throughout the entire southern portion of the belt. In Georgia, Florida, Alabama, Mississippi, and Texas, the damage was considerable; but Louisiana escaped material injury. Owing, probably, to a small hibernation, the worms were not noticed particularly until late in July and August; but then the extremely favorable weather caused such a rapid development and great increase that they became destructive some time before the top crop could be saved. The State suffering the most was Alabama. The worms were more or less injurious in Marengo, Coffee, Clark, Bullock, Lauderdale, Crenshaw, Monroe, Lowndes, and Hale, and especially so in Dallas, Greene, Conecuh, and Perry. In Texas, Bastrop, Burnet, Fayette, Austin, Matagorda, and Waller were damaged, while, strange to say, both south and north of this group of counties the worms were reported as coming too late to do much damage. In this connection we may quote from an interesting letter from an Austin County correspondent, published in the Monthly Report of this Department for September:
As predicted in my last, the Cotton Worm reached us last week, and devoured every particle that was eatable, leaves, blossoms, and small bolls. Never since my knowledge have these worms appeared in such a multitude. After having laid waste our fields, they thronged and blackened our lanes, roads, and highways; they penetrated lawns, yards, and even dwelling-houses, lying in the pathway, requiring the constant use of the broom to repel our loathsome guests. IIens, turkeys, and geese had a feast and grew fat. In this portion of the county the loss was not so severe as the gathering had already begun, and most of the bolls were fully grown; but the southern part, bordering upon an extensive prairie that reaches to the Gulf of Mexico, 200 miles distant, was attacked four weeks earlier, and the loss is a very severe one.
In Florida the damage was very unequal, the crops of Jackson, Jefferson, and Madison Counties suffering severely, while other adjoining counties were exempt.
In 1877 there was a falling off in the numbers of the caterpillars in






CHRONOLOGICAL ACCOUNT OF COTTON WORM INJURY. 31

the States which were injured the most the previous year, while in Louisiana, which almost escaped in 1876, the caterpillars this year were abundant and destructive. The September returns say: "The caterpillar is present in all of the Gulf States, and in South Carolina, but ias done little damage as yet, except in Texas. In several of the parishes of Louisiana the loss is considerable from this cause."
The special feature of the year was the injury in Texas. Early in July the caterpillars were proving destructive in Hardin, Jasper, Brazoria, Atascosa, Victoria, and Uvalde. Iu August one-half of the counties sending in returns were infested more or less seriously. In Lavaca County the crop was almost completely destroyed, and Gonzales County reported a loss of 75 per cent. Before the close of the season Austin had lost 50 per cent., Hardin 75 per cent,, Polk 75 per cent., and Waller, Colorado, Walker, and Fayette were all damaged to some extent. Among the Louisiarna parishes injured we may mention Richland, Clailbrne, East Feliciana, and Jackson. In Mississippi, the southern part of the State, including Wilkinson, Jefferson, and Covington Counties, was overrun, but the crop was not seriously damaged. Alabama and Georgia were comparatively unharmed, while in Florida the worms were numerous, but not particularly destructive. In the annual report of this Department for 1877 the loss from caterpillars for this year is estimated in rountl numbers at $15,000, b00. Concerning the occurrence of caterpillars in 178, we are unable to get very full statistics, since the prevalence of yellow fever in parts of the South rendered corresl)oI dence difficult and drew the attention of the planters from their crops to their personal safety. The worms appeared early in Texas, and were reported soon after the 1st of June from Uvalde, Atascosa, IMantagorda, Brazoria, Victoria, Lavaca, Fort Bend, Austin, Hardin, Polk, and Jasper Counties. In spite of this early appearance they seem to have spread but little, and in none of the counties mentioned did the loss exceed one-fifth of the crop. All through the cotton belt the season was a very fine one, and the crop raised largely exceeded that of 1877. In South Carolina, the worms were reported fiom Richland and Clarendon Counties late in the fall. In Georgia they were not noticed until late in August, and then only in the more southern portion of the State. Baker, Thomas, Dodge, Lee, and Early reported them in September, and later, Dooly, Laurers, and Worth. In Alabama and Louisiana the worms were, as in the prcceding States, not reported until late, and their injuries were not severe. Coffee, Bullock, Covington, Dallas, Barbour, Macon, Baldwin, Crenshaw, Monroe, Conecuh, Dale, Wilcox, Lowndes, Autauga, Jefferson, Hale, Montgomery, Perry, Greene, Sumter, and Pickens Counties, Alabama; and Concordia, Caddo, Franklin, Latfyette, Madison, Bossier, and Bienville Parishes, Louisiana, all returned more or less damage. In two Arkansas Counties-Pope and Crawford-the crop was also damaged. In Florida nearly all of the counties belonging to






32 REPORT. 4, UNITED STATES ENTOMOLOGICAL COMMISSION.

the northern tier were infested, but none badly; the crop of Hillsborough County, farther south, was, however, considerably shortened.
In 1879 the worms were noticed and reported earlier than ever before, but this is due to the fact that active workers, attached to the Commission and to the Department, were on the lookout for them. They were reported in the canebrake region of Alabama by Mr. Trelease, and in the Colorado bottom, in Texas, by Mr. Schwarz, about the middle of May; 1879 was not, however, a bad worm year. Although some localities suffered considerable loss, the general loss was far from great. From the September report upon the condition of crops, issued by this Department, we learn the following: The caterpillars were present in great numbers on the 1st of September in Beaufort County, South Carolina; Baker, Dooly, M1uscogee, Brooks, Lee, and Stewart Counties, Georgia; Putnam, Bradford, Sumter, and Marion Counties, Florida, and, in a lesser degree, in Madison, Leon, Suwannee, and Gadsden. In Alabama, Wilcox, Bullock, Coffee, and Perry suffered considerably, while Dale, Lowndes, Monroe, Barbour, and Conecuh were overrun with less resulting damage. Mississippi reported the caterpillars in Lauderdale, Rankin, Scott, Newton, Carroll, Lowndes, Oktibbeha, Copiah, Sharkey, HIindes, Leake, Holmes, and Jasper. Louisiana sent in not a single report of loss; and Texas only Austin, Trinity, Waller, and Harrison; Arkansas, Drew County. The November report increased this list by Thomas County, Georgia; Alachua, Wakulla, and Hamilton Counties, Florida; Clarke, Bale, and Lee Counties, Alabama; Amite, Newton, and Smith Counties, Mississippi; and Brazos and De Witt Counties, Texas; the two last reporting the crop as being almost entirely destroyed by worms. The year, as a whole, was not a favorable one for cotton; and the crop, as a whole, fell short of that of the previous year in spite of an increased acreage.
In 1880 there seemed to be no especially marked increase in the number of the worms over the previous year. The season was a favorable one for cotton throughout its whole extent in the Carolinas, Georgia, Florida, and Texas; although too wet after August in Alabama, Mississippi, and Louisiana, and dry in Arkansas and Tennessee. As early as June 4, the worms were reported as doing much damage in Bossier Parish, Louisiana, and in one or two Texas counties. In July they appeared in Decatur, Early, Quitman, Sumter, and Dooly Counties, Georgia; Gadsden and Madison, Florida; Bullock, Hale, Perry, Baldwin, Macon, Marengo, and Greene, Alabama; Panola, Covington, Clarke, Kemper, and Simpson, Mississippi; Pointe Coup6e and Madison, Louisiana; Jackson, Falls, and Walker, Texas. The final reports for the season show that the damage in Georgia was considerable in Decatur, Lee, and Quitman; slight, or comparatively slight, in Screven, Troup, Early, Sumter, and Dooly; considerable in Lafayette, Florida, but less in Marion, Gadsden, and Madison; considerable again in Barbour, Elmore Crenshaw, Bullock, Hale and M1acon Counties, Ala-






SUMMARY OF LOSSES IN 1881. 33

b and less again in Marengo, Perry, and Greene; considerable in Panela and Noxubee, Mississippi, and less in Jefferson, Covington, Clarke, Kemper, and Simpson; considerable in Bienville, Caddo, Bossier, and Sabine Parishes, Louisiana, and comparatively small in Washington, Pointe Coupse, Madison, Onachita, Saint Helena, Morehouse, and Calcasien; considerable again in Comanche, Erath, Bastrop, Harris, Robertson Wharton, Matagorda, Brazoria, Fort Bend, Austin, Limestone, Montgomery, Walker, and Brown Counties, Texas, and less so in Polk, Bexar, Karnes, De Witt, Jackson, Falls, Titus, Victoria, Harrison, Coryell, Montague, and Paine. In Arkansas, the crop of lempstead County was damaged.
The following summary of the losses in 1881 is taken from the Annual Report of the Department of Agriculture for 1881-'82: AJAU A.-Tal-ldega: Appeared late and only on luxuriant growth in some bect ions. Lim.stone: Shed more from want ofproper cultivation and rain and drought. Lawree: In low bottom-lands to some extent. Conocuh: All the t~p crop destroyed. Barbour: Partially in many fields rust preceded the caterpillars anld destroyed what they would. Perry: Prairie early and sandy land later. Chilton: About three-fourths stripped of leave early; after rain budded out but made nothing. e thi Kab: Stripped in ome actions. 8int Clair: Some fields were not touched while others were entirely stripped. Cherekee: me fields ripped early, other not at all. Rus ll: On botitomlands early. Marego: Stripped entirely where no poison was ued. ARANsxs.-Heipstend: Some spots none ; other a, high as 50 per cent. Pulaski: Earlier than ever before. Woodrff: Only the foliage and unmatured llls. Jackson : By the Army Worm. Montgomery: Many fields stripped after the cotton had matured. Pope: Later than usnal. ward: Leaf Worm came early but did no damage. Monroe: Whole region stripped bare of foliage. Grioou.-Bibb: On bottom and new land only. Muwsogee: On lowlands early; plands later. Lndes: Second crp of foliageentirely tripped. Hancock: Entirely Slow, wet dlani. Jones: Stripped entirely on red lands; gray land suffered but little. Dly: Only partially. Morgan: In consequence of the very late fall and frot. Lincoln: Few fields. Liberfty: Partially. Early: S.me localities early. (onee: Picking of the best cotton was done before the worns came. F~uu.-Columu : Many fiechs stripped. Madison: Only in portions of the county. Sumter: Was stripped entirely.
TzNNxsaz.-fedford: Boll-wor-s are unknown here, though caterpillars stripped the leaves. Linoln : Stripped of leaves. Dikson: Very little damage done in this county. hite: Boll-worms do the most damage. 8OUTH CAoL .-Oco ee: Only partially in limited loc-alities. Grenl: Crop made before worms came. Nrherry : In some lcalities, but so late in son as not to injure yield; rather benefit it by exposing the unopened bols to sun. AbberiUe: Where it appeared did not more than eat the leave. on the plant. Barnirille: Stripped clean of leaves and young balls, which came too late to make anything. NoRT CAAr1NA.-Ca ne too late t do any damage. Leir: Did not appear only in a few places. Columbus: Only appeared in a few places and too late to do any damage. Cabarr: Did not appear till after crop was picked; they then stripped the plant. Wil.es: A few appeared just before frost, but did no damage. Cumberland: Few fields had the leaves eaten off, but too late to do any damage. Pitt: Few places they appeared, but too late to do y damage. Cleueland: Very little. Lousu-A..- Union: A few places had then reported, but no damage done. Jackon: Stripped, but after maturity. Lincoln: In some places, but not until after it was picked. Franklin: Not until picking was over, then only partially. Et Carroll: Stripped, except very high land or shaded.
63 coN..-3






84 REPORT 4, UNITED STATES ENTOMOLOGICAL COMMISSION.

MISSISIPPI.- Union: In some localities, but after cotton matured. Tate: Second growth eaten by them (leaves) bolls not hurt. Chickasaw: Army Worm destroyed top crop. Alcorn: In a few localities, but after the crop had mostly opened. Prenti8s: Did not appear until about frost, and did no harm. Bankin: Very little, and after bolls were matured. Jeffer8on: Destroyed all top crop. Clay: Bottom crop at maturing. Issaquena: Only partially, and that late. Clarke: Owing to the early drought the leaves became so hard and dry that they made very slow progress. TXA.-Gonzales8: In some places early; others late. Bee: Damage at first of season by Grass-worm. Colorado: In some sections where not poisoned. Denton: Partially by the Web-worm. Lee: Where poison was not used the plant was generally stripped. Houston: In very few sections, and very late. Fise: Came, but too late to do harm. Brazos: Very late; too late to injure. Live Oak: In some localities. Wood: Too late to damage. Lampaeas: Came too late to damage. Milam: Second crop damaged in some localities. Van Zandt: Caterpillars came early and made clean sweep. Grimes: Only top crop injured, which seldom amounts to anything. Palo Pinto: Stripped but very little. Leon: In some places, but too late to do damage. Fannin: Some fields were stripped, but not until it was all opened.

HISTORY OF REMEDIES.
From the early days when the Creoles of Louisiana fought the chenille which was destroying their cotton, with "holy water," down to the present time, when the improved sprinklers, with their extended arms and many jets of poisoned spray, are drawn through the fields, destroying the worms upon eight to twelve rows of cotton at once, it is plain that immense improvement has been made. Let us glance at the steps by which this was brought about.
Naturally the first remedy which the planter would try would be to destroy the worms by hand, and this really was, so far as we can find, the first method used. The next remedy was suggested by the avidity with which poultry devoured the worms. Dr. Chisholm says conceriing his observations in Guiana in 1801-'O2: "A prudent, economical planter will increase the brood of every species of domestic poultry, particularly turkeys; for this has a tendency to diminish the brood of the chenille in a very great degree, while profit arises from the augmentation of useful stock. Turkeys are observed to have a remarkable appetite for the larve of the Cotton Moth and devour prodigious quantities of them." With this remedy, however, Dr. Chisholm's practical ideas seem to cease, for he goes on to describe how the worms may be killed by burning sulphur on a chafing-dish, the plant being covered meanwhile by a canvas hood! By the use of thjs remedy (as Mr. WVailes many years afterwards very justly remarked) a hand might, with exceptional diligence, go over an acre in fifteen or twenty days!
For many years hand-picking and the keeping of large poultry yards were the only remedies practised; yet excellent success was attained where thorough and energetic planters tried to save their crops by these means, as is evinced in the following quotation front Seabrook (183):
The caterpillar appeared in several parts of the field of John Townsend, of Saint John's, Colleton, early in August last. The plants were luxuriant in growth and tender in weed and leaf, and the weather, being warm and rather moist, was altogether






HISTORY OF REMEDIES. 35

propitious tothe spread and multiplying of the worms. By the adoption ofprompt and vigorous measures, some of which are new, and rigid perseverance in their execution, his crop escaped unscathed, while many of his kellow-laborers who lacked faith in any rmedy suffered greatly. In the attainment of his purpose the means resorted to by Mr. Townsend were the following:
1. His pple searched for and killed both the worm nd the chrysalis of the first

2. On the appearance of the second brood he scattered corn over the field to invite he notice of the birds, and while they depredated on the worms on the top of the talks and their upper limbs, the the rkeys destroyed the enemy on the lower branches. 3. When in the sarelia (chrysalis) state the negroes crushed them between their

4. Some patches of cotton where the caterpillars were very thick and the birds and turkeys could not get access to them were destroyed.
5. The tops of the plants and the ends of all the tender and luxuriant branches, where the eggs of the butterly arc usually deposited, were cut off. By these means, resolutely pursued, although at one time the prospect of checking the depredators was most che~rless, not the slightest injury to the field was ostained. The experiment cost Mr. Townsend 2' acres of cotton, about 15 bushels of corn, and the work of all his people for about five days.
It ill be noticed that among tt the remedies used by Mr. Townsend was that of topping the cotton, under the supposition that most of the eggs are laid upon the upper and tenderer leaves. This was one of the early remedies, but has often been urged since, and has its disciples to the present day. As we shll show in discussing preventive measures, it may be employed to advantag in some ceaes late in the season, but at the most critical period of the year the eggs are mostly on the lower part of the Ilant.
About 180 Mr. Wailes first pubicly recommended the carrying of lighted torches through the fields at night to attract and kill the mioths. Soon after, large fires began to be built in different parts of the pllatations for the same pulpoe, and, later, these fires were built upon elevated platf rms ftiored with earth. It is stated, however, b5y )r. J. C. Keal, that Col. F. ). MclDowell, an old Florida planter, had begun the use of fires to destroy the moths as early as 1805. First and last this remedy has been extensively tried; but the general verdict seems to be against its utility. It is held that such fires attract to a plantation many more moths than they kill. One author has even gone so far to dispute that any moths are destroyed in this way, stating that repeated observation has shown to him that the rush of hot air carries them up and away before they can reach they can reach the flame.
Prior to 1855 were published a number of articles recommending the flying of white flags in different parts of the fields, and stating that the moths would oviposit upon them. Each published recommendation, however, was from hearsay, and no one of the writers was able to say that he ad ever seen a single egg upon such a flag. Where the idea started we are unable to say.
Clean cultivation, forcing the cotton, and rotation of crops had all been urged by writers before this, and followed by many planters, no doubt with much advantage.






36 REPORT 4, UNITED STATES ENTOMOLOGICAL COMMISSION.

Many fanciful remedies had also been suggested, such as soaking the cotton seed in a poisonous mixture on the supposition that the egg of the worm was contained in the seed; fall-plowing, on the supposition that the pupa hibernates under ground; burning the cotton stalks, as they were supposed to contain the eggs; burning the nests of the webworms on trees, which were thought to harbor the Cotton Worms during the winter, and many others equally fallacious.
The use of plates with an adhesive sweet of some sort, to attract and capture the moths, had been tried for some years prior to 1855, but we believe that Glover was the first to publicly suggest the addition of poison to the mixture. So also Glover, in his 1855 report, was the first to describe a trap lantern for catching and destroying the moths.
In 1800 the idea of poisoned sweets was elaborated by Mr. J. M. Heard into a patent moth trap, which has been quite extensively used throughout the South, and which is spoken of in the chapter on remedies.
After the close of the war the planters seem to have awakened from the partial apathy which they had before shown on the subject of remedies. In Louisiana a sweep plow was invented which brushed the worms from the plants and buried them under ground. Numerous styles of trap-lanterns were invented; solutions of cresylic soap, carbolic acid, and other less efficacious compounds, such as decoctions of quassia and infusions of China berries, were tried, but with only partial success in the case of the former, and none in the case of the latter.
It was not until 1871 that arsenic began to be used in solution. In January of that year Thos. W. Mitchell, of Richmond, Tex., obtained a patent for its use against the Cotton Worm.
In June of 1872, at the organization of the American Agricultural Congress at Saint Louis, it was our privilege to deliver before the Convention a lecture on Economic Entomology. There were many Southern delegates present, and in the discussion which followed the lecture we suggested, in answer to inquiries from General Win. H. Jackson, of Nashville, Tenn., and Dr. J. 0. Wharton, of Terry, iss., that the Paris green mixture, which was proving so successful against the Colorado Potato-beetle at the North, might be equally efficient against the Cotton Worm ii the NSouth.
In SMay, 1873, having in the meantime experimented with Paris green upon various Lepidopterous larve allied to the Cotton Worm, we read an essay before the second meeting of the Congress at Indianapolis, in which we strongly and unhesitatingly recommended the'use of the grecn for this particular insect. An abstract of the essay was published in the Saint Louis Journal of Agriculture, and this was very generally copied in the agricultural press, especially of the South. The extensive use of the green for this purpose dtes in reality from this period, though there is evidence that it was used in Texas and in Alabama, in 1872, whether as an outgrowth of our remarks at Saint Louis in June,






HISTORY OF REMEDIES. 37

or from the logical reasoning of some energetic planter or planters, it is impossible to say.
Recently, however, Mr. J. P. Stelle, agricultural editor of the Mobile register, has put forth his own claim to having been the first to publicly recommend the use of this poison for the Cotton Worm. This claim he upon an article which appeared in the Regiter in August, 1872.
This article appeared as an editorial in the body of the paper and not in Mr. Stelles agricultural department, a fact which in itself would argue that he was not its author. Moreover, the article does not specifically recommend the use of the green, but simply announces the fact that it is being tried. We quote the paragraph in which it is found:
We have but little to offer in the way of remedies with which to combat this pest of the planter. Hand-picking the plants is urt but hardly practicable in all cases. Fires built aut t the field at night would be likely to do some good in the way of destroying the moth, as it has a natural disposition to fly into them. We know of several persons who are now experimenting with dry Paris green sprinkled upon the plants after having been mixed with 15 or '20 parts dry ahes or blacked lime, and we hope to hear a good report from them.
It is, moreover, an extremely significant fact, and indicative of the authorship of this paragraph, tht in Mr. Stelle's subsequent writings (see, for instance, The Cotton Caterpillar and How to Combat it Successfully," Rural Carolinian, July, 1874) he gives the entire credit of the recommendation to our essay before the Indianapolis meeting in May, 1873; and it is only recently that he has laid any claim whatever to an earlier announcementY
In the fall of 1873 the following circular, doubtless prompted by our Indiaapolis address, was issued and distributed throughout the South by the Commissioner of Agriculture:

PROTECTION AGAINST COTTON INSECTS.

The annual losses of cotton from ravages of cotton insects amount possibly to half a million bales in years of insect prevalence. One-fourth of a million bales would be deemed a light infliction, and yet, at $100 per bale, such a loss would be equivalent to $25,000,000. The methos to be employed for lessening their ravages have been heretofore canvassed by the Entomologist of this Department. The remedy can only be applied by the planters themselves, and their own experience can best render practicable and efficient the means employed.
Numerous correspondents have of late been experimenting with a mixture of Paris gren and flour or plaster, dusted on the plants when wet with dew-a remedy which ha proved very efficient against the Colorado potato-beetle and other insects. Some report this remedy effectual against the cotton-caterpillar, while others declare it of no value whatever; others, still, hesitate to try it for fear of poisoning. It is of the utmost importance that the facts in the experience of planters the present season should be carefully reported, showing the quality and proportions of material used, the method and frequency of its application, and the observed results, that a thorough test maybe made of its value or worthlessness. The answer of the following questions I" ipyk~






38 REPORT- 4, UNITED STATES ENTOMOLOGICAL COMMISSION.
I. What is the result of your experience or observations as to the efficacy of Paris green, or other arsenical compounds mixed with flour or plaster, for the destruction of the cotton-caterpillar I
II. In what proportions, and in what mode, time, and frequency of application have experiments been made ?
III. Have any injurious effects of the poison been observed, either upon the plants or the soil, or in human poisoning in its application, or in the destruction of beneficial insects, as bees, &c. ?
IV. Have you used any other remedies, or means of extirpation, such as fires or torches in the fields to destroy the perfect moths on their first appearance, and with what success ?
Yours, respectfully,
FRED'K WATTS,
Commissioner.
The answers to this circular, published in the Department report for 1873, showed that the green was tried during the season ih seven States and seventy counties, and that its success had been almost uniform.
The'same year several patents were taken out for poisonous mixtures to be used in destroying the Cotton Worm, and some of them reached a great sale for a few years--notably Preston & Robeira's Texas Cotton Worm Destroyer," and Johnson's "Dead Shot." But it has become generally understood that the same ingredients can be used in slightly differing proportions without infringing upon the patents, so that at the present day the patents are generally disregarded.
In the Monthly Report of the Department for November and December, 1872, Mr. E. tH. Derby, of Boston, remarking upon the fact that the worm would not eat jute, suggested that a belt of that plant around a cotton-field might keel.) the worm away. A year later, in the Monthly Report for November and December, 1873, Mr. E. La Franc, president of the Southern Ramie Planting Association, detailed experiments with three fields, which seemed to prove the practicability of the use of jute as a preventive. Subsequent experiments, however, have failed, and it is probable that from this article of Mr. La Franc's have spread the numerous reports of the efficacy of jute, which are to be found in the back files of many Southern papers.
Since 1873 most of the advance in remedies has been in the way of invention or improvement of machinery for the distribution of the poisonous mixture upon the plants. This machinery will be fully discussed in the chapter on remedies.
The cheap arsenical poison known as London Purple was first expe. rimented upon as a Cotton Worm remedy by us during the season of 1878, and the favorable results which followed its use induced extensive experiments the next year.
It is hardly necessary to add that it has grown into great favor where. ever it has been obtained pure and has been judiciously used.
The only remaining remedy of importance-Pyrethrum-was first publicly recommended by the writer for this purpose in first edition of this work, our first experiments with it upon the worms having been made during the summer of 1878.














CHAPTER IV.




THE COTTON WORM IN OTHER COUNTRIES.

Aletia ylina, although widely spread in the Western Hemisphere, has not yet been found, as far as we are aware, in the Eastern. The cotton crop in the Eastern countries, in Egypt, Greece, India, Australia, has its insect enemies: in Egypt, a Noctuid larva; in Greece, various species of Cut-worms; in India, the Teid Boll-worm, Depreswria gossypiella; in Australia, a red bug allied to the tysdercus suturellue of the West Indiess; but Aletia rylina has as yet been found only in North and South America and the intervening islands.
Up to the present time the northernmost point at which Aletia has been collected seems to be1w Quebec; and as to its southern limit, there seems little doubt but that it is found in So Paulo, one of the southern prvinces of Brazil. its western limit is the Pacific, although we have no information as to its occurrence in California, even in the cotton fields in the southern part of the State. It is found, however, upon the coast further south at Mazatlan and Manzanillo, Mexico, as shown in the following extracts from correspondence which we have had with the United States consuls at these ports, Aletia being identified in most ases from specimens received :
CONSULATE OF THE UNITED STATES,
Mazatlan, December 3, 1879.
The Cotton Worm, or as known here by the name of the Army Worm, the Bud Worm, and the Boll Worm, are the worst insect enemies. The regular Cotton or Army Worm attacks the cotton plant every year, but about once in four years is very destructive. It appears to be deposited by a fly on the underside of the leaf, which rolls up, and in a few days the worni, of about 2 inches, appears. During the winter months it disappears. Cotton was first introduced into this State, in 1&3, by an American, Mr. Francis Nolan; it was produced from seed brought from the State of Guerrero. It doet ld in this not grow wiln thiState. The first years but little trouble was experienced from the Cotton Worm; but each year they have given more trouble, especially if cotton is planted again on the same ground. The prevailing direction of the wind during the months from March to July is from the east in the morning, and from the southwest in the afternoon.-[E. G. Kelton, United States Consul.

SMAzAxjLLo, Mxx., Dec er 26, 1879. The larger worm or caterpillar (An omi xylina) has made it appearance on this coast three times during the last twenty years, in 1866, in 1873, and again in 1878. It is a dark green looking worm, with white and black lines, and destroys the cotton plant by devouring the leaves. It is as yet impossible for me to find out the origin or even habits of this worm. I have investigated the supposed causes of its appearance, but without succe; the farmers here have not the slightest idea about it. An apparent 39






40 REPORT 4, UNITED STATES ENTOMOLOGICAL COMMISSION.

coincidence between the appearance of this plague and overflooding of rivers in the cotton regions should be mentioned.
1865, September, high floods, complete inundation of cotton lands. February, 1866, appearance of the caterpillar in small numbers, not causing much damage.
1872, September, floods, partial inundation of cotton lands, high lands and ridges in the valleys not flooded. February, 1873, appearance of the plague, and total destruction of cotton plantations.
1878, September, high floods, complete inundation of cotton-growing valleys. 1879, February, partial plague, small damage done by the caterpillar.
I am of the opinion that the worm has not been imported into Mexico, but originates in the cotton valleys in such seasons, when the peculiar condition of the soil and climate combine to favor the development of the larva.
The cotton lands in this vicinity are bounded on the W. by the Pacific Ocean, on the E. by high mountains, la Sierra Madre, on the N. and S. by dense woods and tracts of uncultivated lands. These circumstances present a great many obstacles to the flight of the Cotton Moth. The nearest cotton plantations, as well to northward as to southward, are at a distance from Manzanillo of at least 100 miles.
Cotton has been grown in the State of Colima for the last fifty years. It does not grow wild, but if abandoned, some plants grow up to good sized trees, bearing fruit regularly every year.
The directions of prevailing winds on this coast are the following, viz:
January, S. and W.; February, W. and N. W.; March, W. and N. W.; April, N. W.; May, N. W.; June, S. and N. W.; July, and W.; August, S. and W.; August, S. and W.; September, S.
and W.; October, S. and W.; November, S. and W.; December, S. and W.
The north and northwest winds blow generally during the day. At night these winds change to the north and northeast.
I give the prevailing winds for the whole year, as our planting and picking seasons here are different from those in the United States.-[Augustus Morrill, United States Consul.
On the Gulf coast of Mexico Aletia is also found. The following account of its work in the consular district of Vera Cruz is from the American Entomologist, Vol. III, p. 179 (July, 1880):
INTERESTING COTTON WORM NOTES FROM VERA CRUZ, MExICO.-In this consular district about 8,000,000 lbs. are produced. The peculiarities of culture are striking. The ground is prepared by removing rubbish, and then the seed is planted by inserting a sharp stick in the ground at convenient intervals; into the holes thus made the seed is deposited and covered by the foot. No plows are used in this preparation for the seed, nor are they often used in the subsequent stages of cultivation. They pull out the larger weeds or use the hoe, confining their labor to little more than such. It is clear from that kind of culture that the cotton plant must be forced into much bad company, and be assaulted with destructive enemies. After extensive inquiries I find no one scientifically informed on the full habits of these enemies.
* * * *
It is a hotly disputed point as to what becomes of the worm during the six or eight years" when it does not appear, and no one in my circuit of acquaintance gives me anything better than a superstition for a solution of the problem. Our climate, never giving us frost, scarcely affects the constant germinal qualities of plants or the enemies thereof, and it has been asserted to me that at one place or another the Cotton Worm can always be found. However, the difficulty I have experienced in obtaining the specimens sent, induce me to doubt the correctness of that assertion.
9 9 9 9 9
The worm has been here as long as cotton has been cultivated by the Mexicans. We have historical accounts that cotton was grown and utilized since the twelfth century, but have no data that it was or was not naturally indigenous. But if said






THE COTTON WORM IN OTHER COUNTRIES. 41

h be reliable it is fair to presume that it was indigenous, because there is no knowledge of commercial relations with foreign contrie at that period.

The winds here are easterly and southeasterly.-8. T. Trowbridge, U. S. Consul, Vera Cruz, Mexico, March 3, 1880.
I send you a bottle containing various kinds of worms that destroy the cotton and plant. They are all I have een able to procure. This is now the part of the year in which the worms usually appear,and they have been gathered near San Andres Tuxtla, o the southern coast fromi here.

On the coast they are called palomas (moth) or salomilla (chrysalis or aurelia). Said paloma is ash-color, and is nocturnal in its habits. The moth produces a multitude of microscopic eggs on the plant, which eggs create the woru, also licroscopic, and which commences immediately to devour the plant, and so continues until it gets to the state of enrolment, in order to pass through the last metamorphosis. I have not been able to obtain sufficient data to say whether they were imported into this count, but I am asured that they do not take their appearance every year at the same place, or, better said, they only come one or two years in succession, then disappear for six or eight years. They are not to be found in all the country at one time. Their reproduction is usually ascribed to our southern coast.
a & S 0
I understand their invasion can be victoriously combated by sprinkling dry chloride of lime over the ground and plants, or an aqueous solution of the same, and I have red this reedy to those living on the coast for a triaL-R. de Zayns Enriques, Vera Crus, March 2, 18w0.

[The worms sent by Senor Enriquez are the genuine Aletia of all sizes, but mostly full-grown. The facts coimunicated in the above reports are most interesting, not only on account of the remote period to which the growth of cotton may be traced o this continet, but also because of the general observations as to the reoccurrence of the insect in njurious numbers at irregular periods only. In other words, the iusect presents the same phenomena in Mexico as in this country, and the same facts upon which the theory of annual immigration to t the United States have been largely based will hold equally true of a country essentially below the frost line. This all goes to prove the correctness of our conclusions that the absence of Aletia during certain years is apparent only, and that its undue multiplication during other years is paralleled by similar phenomena in respect of many other insects, and notably of the Northern Army Worm, the apparently sudden appearance and disappearance of which over vast regions is even more marked than in the case of Aletia. Yet, as we have shown in the case of both these insects, they may always be found in limited numbers even when their presence is not suspected.]
The following notes on the appearance of the worms in Yucatan, we extract from our correspondence:
UNITED STATE8 CONSULATE AT MERIDA,
Noviber 2, 1879.
The culture of cotton is very slight here. It is cultivated only in the southern part of this city, and in very small quantity; it grows to the height of 12 feet. No other int enemies are known but the worm, and this worm is exactly as described; that a green worm with white lines and black dot. This worm is always on the cotton leaf, and there is no doubt that eating the leaf it kills the plant. It does not touch the boll, as it remains always on the leaf. If possible I will send specimens.
Cotton ha been growing here for more than sixteen years and grows wild, but it is erior to the cultivated plant. The prevailig direction of winds during March, April, June, and July is generally southeast.-fM. Ceballos U. Vice-Consul.






42 REPORT, 4, UNITED STATES ENTOMOLOGICAL COMMISSION.

Passing over to the West Indies, we find that the caterpillar was destructive to cotton in the Bahamas from the earliest cultivation of the plant. In 1788 we are told by various narrators that 280 tons of cotton were destroyed. In 1794 two-thirds of the crop on Acklin's Island was lost. From this time up to the emancipation of the slaves, in 1834, the worms were injurious every year, but at this time the cultivation of the crop ceased until the outbreak of the civil war in the United States, when it was again begun, only to cease at the close of the struggle. According to the inhabitants, the Cotton Worm has not been seen since a great hurricane which visited the islands in 1866, and Mr. Schwarz, in the spring of 1879, was unable to find a trace of it in any stage.
In Cuba the cultivation of cotton ceased some fifty years ago, and Mr. J. P. Guarch6, United States consul at Matanzas, wrote the Department, in 1855, giving as the reason the superior profits of sugar cane and tobacco, and the fact that "the soil generates a worm which attacks the cotton plant and destroys the greater part of the crop almost every year. This worm is said to infest the plantations of our Southern States, but its ravages there are represented -to be trifling in comparison with what they are here."
In Santo Domingo, Porto Rico, Trinidad, Barbuda, and Guadaloupe, the Cotton Worm has probably always been present, but we have no absolute information beyond the fact that in the British Museum Catalogue of Lepidoptera, Part XIII, p. 989, four specimens of Anomie grandipuncta (synonym of Aletia xylina) are entered from Santo Domingo.
In Martinique it exists without much doubt, as appears from the following:
UNITED STATES CONSULATE,
Martinique, W. I., December 11, 1879.
Cotton is not cultivated to any extent in Martinique. There is not a cotton plantation upon the island; there are only a few traces here and there, and these grow wild upon the southern part of the island. The worst insect enemy is a green-looking worm with white points on either side. I am told that this worm has been here since the first cultivation of cotton upon the island. The prevailing direction of the wind during the months of March, April, June, and July is east-northeast.-LW. H. Garfield, United States Consul.
Cotton was formerly one of the staple crops of this island, and Mr. Grote in his report to us states that he was informed by the Hon. Robert Toombs that in 1801-'02 there was an emigration of French cotton planters from Martinique to Georgia on account of the ravages of the Cotton Worm.
In the northern countries of South America Aletia is abundant without doubt. The British Museum (loc. cit.) possesses specimens front Venezuela, and the following note from Maracaibo refers to this species: UNITED STATES COMMERCIAL AGENCY,
Maracaibo, Venezuela, February 18, 1880.
The worst enemy of the cotton plant is the caterpillar. There are two distinct kinds. One is green and rather small, and the other kind has a green belly






T CO ON WORM IN OTHER COUNTRIES. 43

and yellowih back with brown stripes. * The caterpillar generally appear in the -time; that i to say, in February and March, and at times in such quantities th they succeed in destroying whole plantations of cotton. If, however, the rainy continue a short time beyond their usual period, they are almost all destroyed by the rains.
These caterpillars have been known ever since the first time that cotton was raised ere, and, so far a I can gather from information received, are indigenous to the countr and n noway mported from elsewhere. The winds that prevail in that part of the country are north-northeat and south-southeast.-[E. H. Plumacher, Commercial Agent.
The smaller caterpillar referred to is Aletia, and the larger one a large sphingid larva.
In British Guiana the Cotton Worm was in former years very abundant and destructive. Dr. Chisholm has given a long account of its method of work and the remedies, which is quoted freely in the Report of the Department of Agriculture on Cotton Insects, 1879 (pp. 72, 73). Dr. Ure (1835) also states that the Chenille is the most destructive enemy to the cotton crop in British Guiana.
In Dutch Guiana the Cotton Worm has always been destructive, and Mr.F.W. Cragin, United States Consul at Paramaribo, writing to the Department of Agriculture, in 1856, identifies the destructive insect with Koctua ylina Say.
In Brazil, A. ylina has been found at various points. Our most trustworthy information is contained in the report of Mr. John C. Braner (Appendix V). Messrs. Bramer and Koebele, as shown in this report, reared this sps species from the larva at Bahia and at Bonito (Province of Perunmbico). In the British Museum list previously cited, A. grandipuncta is given from Santarem (Province of Para). The following concerning the Cotton Worms at Bahia is from the American Estomologist, Vol. II, pp. 128, 129 (May, 1880).

COTTON CULTURE AND THE INSECTS AFFECTING THE PLANT AT BVAmA RRALT.
Cotton is not grown at present to any considerable extent in this province, and h ceased to be an article of exportation. The cultivation is simple in the extreme, re quiring little care or attention, but owing to the distance from this part of the cottonproducing districts, the cultivation has long since ceased to be remunerative. The insect enemies of the cotton-plant which particularly attack it, consist of two species of moths, which in the form of worms or caterpillars prey upon its leaves and stalk as also the cotton pod itself. It is also attacked by a peculiar species of bug, a specimen of which is forwarded, and by the grasshoppers, which commit great ravages on the foliage and the tender stalks.
The "Cotton Worm as described by Profesor Riley is somewhat different from the worm found in this province, differing in color and other respects, but it is no doubt of very similar character.
The ravage committed by them is greater in the dry or summer months, say September, October, November, and December. This Cotton Worm is believed to have been always in the country, and not imported. Cotton has been grown in this part of Brazil for as long a time as any other produotion, and it is also found growing wild.

*Brewter's Edinburh Encyclopedia: Article Cotton.






44 REPORT' 4, UNITED STATES ENTOMOLOGICAL COMMISSION.

The prevailing direction of the wind during the months of March, April, June, and July is easterly, varying from N. E. to S. E.-Richard A. Edes, U. 8. Consul, Bahia, Brazil.
One of the caterpillars referred to by Mr. Edes is the larva of a species very near and perhaps identical with Aletia argillacea Hiibn., as proven both by specimens received from him and others collected and bred by Messrs. Branner and Koebele, while the other is undoubtedly Aletia sylina.
From Pernambuco we have had the following excellent account:

UNITED STATES CONSULUTZ,
Pernambuco, March 20, 1880.
* The foes most fatal to the cotton plant are the different kinds of caterpillars, which in some years increase to a frightful extent, destroying entirely the crop and the pasturage; the absence of rain, and "the blight." * The Cotton Worm or caterpillar, Anomis xylina, particularly described in your letter, attacks the plant in these provinces. It appears simultaneously with the other varieties at the beginning of the rainy season, and never alone. It comes and disappears with the rain.
So far as can be ascertained from observation, the Anormis ylina is believed to be a native of the country. During some entire years it is extremely rare to see a caterpillar, whether there be sun or rain, wet or dry weather. Some varieties, however, seem consequent upon the action of the sun, and others upon the action of the rain, appearing and disappearing as if by enchantment-Andrew Cone, U. 8. Consul.
In the more southern provinces of Brazil there is also a destructive Cotton Worm, but its identity with Aletia has not been established. The following paragraph from the report which Prof. J. E. Willet made to us in 1878 refers to the work of this worm:
Dr. E. L. McIntyre, of Thomasville, Ga., writes: I settled in the province of Sao Paulo, Brazil, in the year 1866, and remained there eight years and a half. The cdtivation of cotton was of recent date then, and they were planting their fourth crop when I arrived. Prior to the year 1863 there had been some cotton planted in the country, perhaps of an indigenous variety, but no one had ever observed a Cotton Worm, and I believe they had never existed there. In 1862 the price of cotton offering great inducements to Brazilian farmers, they sought to procure seeds, but none could be had, and I am informed the seed then bing used was brought from New Orleans. The first year no caterpillars were seen, but after the second they commenced to eat the leaves, and had increased to such an extent that when I moved from there the cultivation of cotton was nearly abandoned."














CHAPTER V.



ON THE ANATOMY OF ALETIA.
B CHARLES SEDOCwIK NOT AND EDWARD B~aG~e.
[Plates VI-XI.]
The following chapter was prepared at the request of Professor Riley, to whose kindness we are indebted for the material upon which our observations have been made. Several untoward circumstances have contributed to interre with the progress of the investigation. The work was bemn by Dr. Minot, who was subsequently joined by Mr. Burgess, in the hope that our joint labors would prove more efficient Nevertheless we find it necessary to leave various points undecided. This incompleteness is partly due to to the unavoidable impelIrfectiofn of preserved specimens,* and artly to the scanty light yet throw n on ect anatomy and phytiology.
ANATOMY OF THE LARVA.
The external anatomy of the larva need not be again described in this chapter. There are only a few points to be noted in egardto to he legs, the previous descriptions of which are somewhat incomplete. The true legs, Plate V, Fig. 4, are conial, treejointed, an(l provided with a terminal hook, Fig. 6, which is curved toward the median line of the body, and has at its base a thick swelling, usually described as a fleshy pad; the adjective fleshy is hardly appropriate, as the p)ad is covered by a well-developed, hard crust. Theie are two hairs on the first joint, the lowr being much the slender, There are four hairs on the lower part of the second oint, two on the inner edge rather stout and curvig, and one fine one just below them, and a long one in front. On the last joint again are four hairs, all near the terminal claw, namel, a small one in front, a thick, curving one on the side, another thick, curving one just above the pad of the claw, and immediately above this the fourth hair, which is shaped something like an Indian club, and is apparently somewhat flattened. The constancy of form and disposition of these hairs lead us to think that their arrangement must be of some importance, therefore we have given this detailed description.
*Some mater preserved i a per oet solution of chloral-hydrate was found very useful. With this specimen should be opened in several places to allow the fuid to penetrate into the laterfe. Indeed this sheald be done with alooholic specimens als45






46 REPORT 4, UNITED STATES ENTOMOLOGICAL COMMISSION.

The false feet or prolegs, Plate VI, Fig. 2, of which there are five pairs, the first pair considerably smaller than any of the others, as is well known, differ entirely from the true, anterior or permanent legs. They are thicker, cylindrical, and one-jointed ; they have a few long hairs, and are armed with a row of a dozen and a half curved hooks. The hooks turn towards the median line of the body; they diminish in size from the center of the row towards each end. Each hooui consists of a more cylindrical, large basal portion, which appears to be chiefly imbedded in the flesh of the foot, and a recurved hook proper, Plate I, Fig. 3, which has a very thick cuticula. There is also a pigmented pad, which lies over the base of each hook on the inside of the foot. We could find no certain evidence of a second row of hooks such as have been described in many caterpillars, though possibly there are very smallclaws on the pigmented pads above described.
The markings, colored stripes and dots, that decorate the larva, are produced by various means, partly by deposits in the matrix of the crust (epidermal cells), partly by colors of the crust itself. The darkbrown color belongs to the crust, and is peculiarly distributed in a manner that has not, so far as we are aware, been described hitherto. Upon the outside of the crust is a very thin but distinct layer, which in certain parts rises up into a great number of minute, pointed spines that look like so many dots in a surface view, Plate VI, Fig. 8. Each spine is pigmented diffusely, and together they produce their brown markings. The spines are clustered in little groups, one group over each underlying matrix, or epiidermal cell.
The stigmata of the larva are small vertical fissures on the sides of the segments. The first, fourth, and subsequent segments have each a pair, making nine in all; there are none on the second and third rins. Viewed from the surface they are seen to be provided with an anterior lip, which is simple, and a posterior lip, which bears a projecting lever. Both these lie quite deep down and serve to close the trachea. Above each lip are several rows of hairs that are short, branching, and spinelike. The stigmata form the subject of a recent excellent memoir by Oskar Krancher,* a pupil of Rudolph Leuckart, the distinguished professor of zoology at Leipzig. On pages 543-546 of this essay the stigmata of caterpillars are fully described. According to Krancher, the lever bearing, or posterior, lip is more developed than the anterior. (The former was named by Landois the Verschlussbiiel, the latter the Verschlussband; but these names are not specially appropriate, and we prefer to use anterior and posterior lip instead.) The lever arises from the upper end of the posterior lip. In most of the diurnal lepidoptera it is a simple chitinous rod, but in some of the Bomibycide it is more complicated. Attached to the lever is a double muscle; one part, running to the lower end of the lever-bearing lip, serves to approximate
Okarr rancher. Der Bau der Stigmen be den Inaektcn. Zeo1tchr. f. wise. Zoologie, XXXV, 1881, pp. 505-575, Taf XXV11I-XXIX.






ANATOMY OF THE LARVA OF ALETIA. 47

the two lips, and so close the opening between them; the other part is attached to the neighboring epidermis, and serves to open the lips. Only this latter division of the muscle, which is considerably the larger, was described by Landois.*
The internal anatomy of the larva agrees closely with the lepidopterous type, as established by previous observers. In the head, Plate VII, Fig. 1, the di estive.canal begins with the large mouth mi, lined by a dark, firm cuticula and passing over into the narrow muscular cesophagus, Oc. Behind the mouth is a projecting pointed process at the tip of which opens the salivary duct. Above and in front of the mouth there is a distinct mass of tissue, of a fibrous, areolar character, spreading out fin-like from the upper wall of the esophagus and attached in front to the lower part of the clypeus and to an endocranial process. In this mass of tissue lies the small frontal ganglion. Above the esophagus is the brain, br; below it the sub~sophageal ganglion S, connected by a short coinissure with the first ganglion of the ventral chain.
The rest of the internal anatomy is illustrated by Fig. 1, Plate VI. In the first (thoracic) segment the The large stomach alone represents the entodermic canal, and presents
Landois. Zeit. wiss. Zoologie, 1867.






48 REPORT. 4, UNITED STATES ENTOMOLOGICAL COMMISSION.

the same essential peculiarities of minute structure as were described by Minot* in the orthoptera. The lining epithelium is thrown up into folds so as to form imperfectly differentiated glandular follicles. If the epithelium be brushed off, the characteristic arrangement of the muscular fibers can be seen, Plate VI, Fig. 7. There is an internal coat, composed of a great number of pale fibers running transversely around the stomach and more or less parallel to one another. Outside are the longitudinal striped muscles, which are distributed in single bundles, I 1, and do not form.a continuous layer. Each bundle is composed of a number of fibers and pursues its own course; the bundles are not parallel, but sometimes two bundles unite, or are connected by a third; their general trend is longitudinal. Finally it must be mentioned that numerous tracheal branches penetrate the muscular layers, and ramify through both them and the connective tissue.
EXTERNAL ANATOMY OF THE IMAGO.

To prepare the external skeleton for examination the following method is satisfactory and convenient. The whole insect, either in the fresh state or after preservation in alcohol, is placed in a test tube with a solution of caustic potash and carefully boiled over a flame for a couple of minutes. The specimen is then thoroughly washed with water, to which a little acetic acid or vinegar is added to neutralize the alkali. The specimen while in this state may be brushed with a camel's-hair pencil, and most of the scales removed. It is best to put it next, for twentyfour hours, in strong alcohol and to then complete the brushing upon the hardened object. With. a little care and patience all the hairs and scales can be removed without injuring the crust.
A view of the exoskeleton of the female is given on Plate VIII, Fig. 1. We shall follow Mr. Burgess' memoir upon the Milkweed Butterfly,f as to the homologies and nomenclature of the parts. The head is more triangular in outline, when seen from the side, than in Danais, and the eyes, E, are relatively smaller. The palpi and maxillm are very similar to those of the butterfly. The antenna, a, are thicker and the enlargement of the two basal joints is quite marked. The thorax is large and compact. The first segment (I) is small, the second (I) by far the largest of the three. The prothorax is connected with the head by a narow neck, which is perhaps really the anterior portion of the first thoracic segment. This point is better shown in a view of the underside Plate IX, Fig. 1. The front legs are there removed; the insertion of coxme into the thorax is shown at 1; just in front of this insertion is a thickened ring of hard crust; farther forwards the integument is membranous, and the prothorax proper becomes directly continuous with
Minot, C. S. Histology of the locust (Calotenus): and the cricket (Anbru): Chapter X, in Second Report of the United States Entomological Commission. 1880. Pp. 183-224. Plates II-VIII. t Burgess, Edward. Contributions to the Anatomy of the Milkweed Buttertly (Danais archippus, Fabr.). Anniv. Merm. Boston Soc. Nat. Hi8t.. 1881.






EXTERNAL ANATOMY OF THE MOTH. 49

theneck. So, too, a median section shows that the neck and prothorax are reilly one, Plat VIII, Fig. 2. Two pendulous lobes sa, Fig. 1, Plate VIII, project from the upper side of the prothorax, which appear to belog the scutum, but their real homololies are not yet determined with certainty. They are constricted around their bases, so as to be quite movable. Upon the sides, just behind and below them, lies the first spiracle, ~'. Below the spiracle are two pieces of elongated shape, running down to the insertion of the coxe; the anterior piece, eps', is the episternum, and meets its fellow on the ventral side, forming a median suture between the two coxal articulation, Plate IX, Fig. 1; the posterior is the homologue of the epimeron of the segments.
The mesothorax Plate VIII, Fig. 1, 1, is the largest segment of the body. It is longest on the upper side. The principal dorsal piece is the big scutum, s, below the lateral edge of which springs the front wing, '. Over the base of the wing runs back the large patagim,pt, which is very much developed; its only connection with the body is in front, where it bends over and, as it were, hooks around the front edge of the wing. The scutellum, m, is isalso prominent and extends for some distance over the metathorax. The episternum, eps, is an oblong piece which runs backward, beginning just underneath the front end of the patagium, and is joined behind to the epimeron, epm2. It is united below with a double piece, st, which extends downwards and backwards to the coxe, cc. This piece was determined by Dr. Packard, in Attacus, as the sternum, and his nomenclature was followed by Burgess in his article on Danais. From our study of the Cotton Moth, it seems doubtful whether this interpretation can be sustained. The piece is double on each side, as can be especially well seen in a ventral view, Plate IX, Fig. 1. The same aspect also shows that the two pieces do not meet in the median line, but are separated by a clear triangular space, behind which lies a pair (a, a) of pieces which separate the coxe and meet one another in the median ventral line. These are perhaps the real sternal pieces. In any case it is evident that further and extended study is necessary to elucidate the real morphology of these numerous components of the thoracic skeleton. The epimeron, ep m (Plate V III, Fig. 1), is quite large and complicated. It consists of a hard V-shaped piece, between the two legs of which is a large, triangular membranous area. The anterior leg of the V is much the broader, and joins above to the episternum, and in front to the part marked st, which Packard has held for the sternum. The membranous portion between the legs presents an inconspicuous structure, which is perhaps a spiracle, although this could not be certainly established. The coxal joint, 2d, tapers rapidly; examined from the outer surface it appears to consist of two pieces; the anterior piece has been called the coxa, the posterior the trocantine by some authors.
The metathorax (III) is particularly puzzling on account of its very complex structure, due at least in part to the development of numerous
63 CON G-4





50 REPORT 4, UNITED STATES ENTOMOLOGICAL COMMISSION.

air-chambers in the interior, accompanied by manifold'ingrowths of the outer crust to serve as partitions between the adjacent air-chambers. As the ingrowths are connected with divisions of the exoskeleton, this last becomes very complicated, especially in the posterior lateral region below the wing and above the leg. The scutum, s', is well marked; immediately below it arises the hind wing, w2. The piece which Burgess determined as the scutellum in Danais we have not found in Aletia; but what in the butterfly appears merely as the tip of the scututm is distinctly differentiated in the moth and is very probably the true scutellum; in this case the part so named in Danais would have to be considered as the post-scutellum. On the front edge of the segment, between the front edge of the wing and the coxal joint, is a single piece, eps3, which seems to correspond to the two pieces, eps2 and St2, of the mesothorax, fused into one. In the posterior part, epm3, there are a variety of structures, of which the most important are two, marked A and B. The former is a little quadrangular flap, which hangs down from just below the posterior edge of the hind wings. The latter, B, is a deep-lying, oval, pellucid membrane, which we think is probably homologous with the tympanal membrane of grasshoppers. The relation of these parts is better shown in the enlarged figure, Plate XI, Fig. 3, in which the oval membrane, B, and the flap, A, are both very distinctly drawn. We have not succeeded in observing any spiracle on this segment. The boundary between the metathorax and the abdomen is not clearly marked externally. The coxal joint, cx3, is similar to that of the second leg.
A. H. Swinton has published a paper on the organ of hearing in lepidoptera,' in which he refers to the oval disk, which we have interpreted as a tympanum. According to Swinton, a nerve passes from the third thoracic ganglion obliquely across and round the elevator muscle of the hind wing to the supposed tympanum, where it is connected with a structure (Swinton's membranous vesicle") which is apparently identical with the structure in like position in the grasshoppers, which latter was likewise originally described as a vesicle, but is now known to be really a cluster of rod-bearing, terminal organs, such as are now known to be the essential-constituents of tympanal organs. For a general account of these apparatus see the r6sum6 by C. S. Miuot.t It is probable that the part we have described in moths is a real t> mpanum, and entirely homologous with that of Acridians, but the matter must remain uncertain until the terminal rods have been actually found.
The abdomen consists of nine segments, numbered 1-9, the last two not showing in the figure, being retracted into the seventh segment. The first is smaller than the second and succeeding segments, and, therefore, appears as a sort of thick stalk uniting the abdomen with
Swinton, A. H. On an Organ of Hearing in Insects, with special reference to the Lepidoptera. Entomologist's Monthly Mag., XIV (1877), 121-126.
tMintA, C. S. Comparative Morphology of the Ear. Fourth Article. American Journ. Otology, IV (1882), 89-168.






EXTERNAL ANATOMY OF THE MOTH. 51

the thorax. Each of the segments consists of a dorsal, two lateral (one on each side) and a ventral piece. The side piece or membrane of the first seven segments bears a spiracle. The first segment, in its transverse diameter, is nearly as broad as the thorax, but its dorso-ventral diameter is barely half as great. In front it bends over and inwards, especially at the sides, so that here (see Plate II, Fig. 3) the crust, where it joins the thorax, faces towards the head. It is here that the spiracle
(sp) is placed, so that in a side view of the abdomen we see the edges of the spirale, and not its opening, as in the other segments; the spiracle looks forwards.
The structure of the spiracles is interesting. They are all essentially alike. Plate XI, Fig. 1, represents that of the second abdominal segment. The spiracle is a vertical fissure with two lips, of which the anterior is connected with a long tendon, to which are attached the muscles which move the lips. Outside the lips is a row of stiff hairs, or spines, which, standing out from the borders of the fissure, reach towards its center. so that those of the opposite sides nearly meet in the middle. Fig. 2 of the same plate gives a more magnified representation of l single spine. It rises from a pore-canal (or tube running through the cuticula), makes a bend at the start, and then runs out nearly straight, a thick stem, from the outer half of which arise a number of oblique prickles or thorns irregularly placed. The shaft consists of a hard sheath and a core or pulp. The hairs on the front edge are a little shorter than those on the posterior. At the top and bottom of the fissure the hairs become very small. The purpose of these spines is undoubtedly protective; they serve to prevent the entrance of foreign bodies, like the similar structures in the spiracles of the caterpillar. In the adult there is a single row of long spines; in the larva several rows of short spines.
The legs offer little requiring special description. The tarsal joints are five on each leg. After removal of the scales they are seen to be armed with a double row of spines on their inner margin (P1. IX, Fig. 2), except the last joint,which has only hairs. The spines are shortest on the upper part of each joint and increase towards the distal end, the lowest spine being the longest. The end of the last joint bears in front two long, curving hairs, and behind the two recurred hooks, between which is placed the soft hairy pad, or pulvillus, p. The other joints are distinguished by their gradual diminution in length, the first or upper being the longest and having also the largest number of spines, as well as the greatest intervals between the adjacent spines. The scales on the legs are peculiarly grouped, being inserted in little clusters of some 10 to 15. Each cluster is very compact and elongated, in the sense of the long axis of the limb.
The scales are flattened hairs, divided into a blade of variable shape and a short pedicel, by which they are attached to the skin. The blade consists of a central portion, homologous with the core of hairs, and






2 REPORT 4, UNITED STATES ENTOMOLOGICAL COMMISSION.

a cuticular membrane, consisting, of course, of an upper and lower lamina, united at their edges and continued on the pedicel. Burmeister gives it as his opinion that the scale is empty between the two lamine; but we cannot accept his view, because in those scales we have examined there is always an internal pulp, which often contains coloring matters. The scales have longitudinal strih, which are produced by folds of the outer surface or lamina, as is at once shown by a cross-section of a scale (Plate IX, Fig. 1A). The upper surface is more nearly flat. The lower surface is recurved on each side. The scales are thickest in the middle line and thin out towards the edges. All these features werelikewise observed by Burgess in Danais, and it is probable that they are common to the majority of the lepidopterous scales. There has been much dispute concerning the nature of the strike on the scales, and Burgess was the first to describe their real character. Certainly Burimeister is in errorwhen he says: "Il n'estpas douteux que les stries bien visibles des 6cailles soient des filets 6lev6s au c6t6 interne de la lame supdrieure, se pronongant au c6t6 externe seulement comme stries finement imprim6es." In many species, especially of butterflies, there ae transverse stria~, which are said by Burmeister to be confined to the inferior lamina. In conjunction with the longitudinal strio, they divide the scales into little squares. There is great variety in the form of the scales, but the study of these variations has hitherto borne little fruit. R. Schneider has published a memoir on the form and distribution of the scales over the body in Lepidoptera, treating the subject with considerable detail. More interesting is Burmeister's essay, which contains the best general account with which we are acquainted.
The scales are inserted into peculiarly-shaped oblique pore-canals (Plate XI, Fig. 5). They begin on the outer surface with a wide open funnel that leads into a bulb or spherical dilatation of the pore. From the deep-lying surface of the bulb runs inward a fine tube. Apparently the stalk of the scale fits into the outer funnel, and is attached to the bulb.
The distribution of the scale pores is characteristic; they lie in little groups, which tend to spread out in lines having the same general trend, but never strictly parallel with one another (Plate XI, Fig. 4). On the legs, as already mentioned, there is a similar grouping, though not identical with that shown in Fig. 4. On certain parts, as, for example, the patagia and the membranous portions of the thoracic crust, the pores are scattered more evenly, each by itself.
The best account of the structure of the maxillm, or proboscis, of butterflies is that given by Burgess, and an examination of this organ in Aletia reveals the same essential structure as in the butterfly, so.that we may dispense with a detailed account. Plate XI, Fig. 6, represents
Burmoister. Description physique de la R6publique Argentine. Torme cinquibme. L6pido. pt6res. (Examon sp6cial des Ecailes, pp. 21-28.) Bu6nos-Ayres, 1878. t R. Schneider. Die Schuppen an den verschiedenen Fliigol- und K irpertheilen der Lepidopteren. Zeitschr. f. d. geanmmt. Nat.-Wiss. I (1878), pp. 1-59, Taf. I-IIL






INTERNAL ANATOMY OF THE MOTH. 53

just the tip, to show its peculiar outline and the spine-like structures, which probably have a sensory function. They are present in all Lepidoptera, but under a great variety of forms; in Danais they are reduced to small warts, but in many other genera they are large and conspicuous; for details the reader may consult Darwin and Breitenbach.* The spines are evidently modified hairs, for they are each placed over a wide pore-canal of the cuticula, and are themselves pointed chitinous tubes, as shown in the figures (Plate XI, Figs. 6 and 8). The spines consist of twd parts, a cylindrical basal joint and a double outer portion, compo ed of two tapring horns (Plate XI, Fig. 8). 8). In some of the larger spines one of these horns is much the greater of the two, and seems to be a direct, spur-like continuation of the base, while the shorter fork is articulated to the proximal joint. In the smaller spines the inequality of the two forks is much less; the long fork is most developed on the spines of the dorsal side of the maxilla. There is difficulty in making out these characteristics in all the spines, as they often lie on the slide i positions unfavorable to microscopic examination, and there remain many points undecided. The largest spines are found a little way from the tip; on the very tip of the trunk they are a little smaller, and towards the base of the proboscis they gradually grow smaller and smaller, and lie further apart; they are not found on the basal half of the organ. Upon that edge of the maxill which is dorsal when they are extended, are hairs such as are represented in Plate XI, Fig. 7. These hairs are for the most prt iclined away from the tip-like barbs. Whether they are stiff, so that they serve to lacerate the flowers attacked by the moths, we were unable to determine; that this function is performed by the large spines is, we think, improbable, although Professor Comstock has suggested this view.

INTERNAL ANATOMY OF THE IMAGO.

The digestive canal of Aletia closely resembles that of the Milkweed Butterfly, Da ai areipps, as described by Burgess. We shall therefore follow his account.
The canal traversing the proboscis opens into a large muscular pharynx, which occupies much of the lower part of the head, Plate VII, Fig. 2. The pharynx is oval, and is suspended by at least two pairs of muscles, one dorsal, mi', and one frontal, mn. At the anterior border of the pharynx is a triangular muscular flap, the epipharynx, mn, overlying the opening of the proboscis, and serving as a valve to close the latter. The pharynx shows two layers of muscles, an outer, thicker one of longitudinal fibers, and an inner of transverse fibers. The pharyngeal cavity extends obliquely upwards from front to back, and is much broader than high.
SThe pharynx, as is evident from its structure, serves as a pumping Darwin Quart Journ. Micros. Sci., XY, 385. Breitenbach. Arch. fUr mikros. Anat., XV, 8, and XVI. 308. Jena. Zeitechr. f. Nat. Wias.






54 REPORT 4, UNITED STATES* ENTOMOLOGICAL COMMISSION.

organ to suck the liquid food of the animal through the proboscis, and force it backwards into the digestive canal, the process being as follows: The proboscis is unrolled, and inserted into the nectary of a flower; at this moment the muscles which suspend the pharynx contract, and its cavity is thus extended, creating a vacuum, which must be supplied by a flow of honey through the proboscis, into the pharynx. When the latter is full its muscles contract, the valve closes the aperture to the proboscis, and the honey is forced backward into the esophagus. The pharynx is then again opened, and the same process is repeated. To prevent the food being sucked back from the cesophagus, it is probable that some of the numerous fibers in the muscular sac near the origin of the former can, by contraction, close its opening; but in any case, as the proboscis presents a free tube, and the esophagus leads into the closed alimentary canal, it is evident that the former offers the easiest route for a supply to fill the vacuum produced in the pharynx." (Burgess.)
The organ just described escaped the notice of entomotomists until discovered by Burgess, and its functions were conjecturally ascribed to other parts. The so-called I sucking stomach' thus received its name from earlier writers, and when its structure was better known and such a purpose negatived, the capillarity of the fine tube of the proboscis, and even a peristaltic action of the latter, have been suggested to explain the power possessed by the butterfly to suck up its food."
At the upper extremity of the pharynx opens the narrow esophagus, oe, and at the lower edge of the hypopharynx the common duct of the salivary glands, sal, discharges into the expanded base of the proboscidean canal. These glands consist of two long convoluted tubes, extending along each side of the thoracic central nervous system. In the general figure, Plate VIII, Fig. 2, the glands have been removed, in order to show the course of the esophagus and ganglionic chain.
The esophagus, Plate VIII, Fig. 2, oe, is a slender and delicate tube leading from the pharynx above, and after piercing the nerve commissure between the brain and the succeeding ganglion, passes straight through the thorax into the abdomen, in the very base of which it separates into two short branches, the upper leading into the food reservoir, the other the true stomach.
The food reservoir, fr, (or so-called sucking stomach), is a large membranous sac filling the anterior end of the abdomen; its walls are a very delicate cuticle, which is interiorly thrown into very curious labyrinthine wrinkles; near the neck is a region armed with singular processes or spines, scale-like in shape, each scale being armed with some six or eight very sharp teeth. The neck has an investment of transverse, annular muscular fibers.
In alcoholic specimens the food reservoir is much crumpled, and in all specimens opened was empty. There are some indications that the sac is not a simple one, but has secondary lobes or partitions; but this






INTERNAL ANATOMY OF THE MOTH. 55

point is still unsolved. Since the organ is not for sucking, as long supposed, and is evidently not digestive, it seems likely, or at least possible, that it serves simply as a reservoir. It is first developed in the pupal stage.
In a lateral view, as in Fig. 2, the neck of the reservoir is concealed by the anterior end of the stomach, which projects into two short lobes on each side of the neck.
The stomach, st is very much smaller than than in the larva, for it barely extends through four abdominal segments. Its walls have the same two muscular coats as we have described in the larval stomach, ride supra, and the epithelial lining is thrown up into beautiful glandular corrugations. The stomach is overlaid with the convoluted malpighian vessels, mn, six in number, three of which, on each side, unite and open by a short, common duct into the posterior end of the stomach. At the end of the stomach begins the peculiarly coiled small intestine, i, which passes to the left of the bursa copulatrix in the female, and of the genitalia in the male. The intestine passes into the wide terminal division, or rectum, R, from the front end of which runs out a curved blind pouch or cecumn, c. In Danais the terminal division is clearly separated into an an anterior part or colon, and a posterior part, or true rectum, but the rectal region is less noticeable in Aletia.
The course of the aorta, or anterior extension of the heart, in lepidoptera, was not correctly described by the older authors. Burgess observed its strange bend in the butterflies, and has since studied it in several forms of lepidoptera, and published his results in a short paper.* In this article he describes and figures the course of the thoracic aorta in a noctuid. In Aletia it enters from the abdomen behind, bends immediately upwards, widens rapidly, makes a slight crook, and then, reaching the dorsal wall of the metathorax, to which it is secured by fibrous tissue, it makes a sharp bend and runs back upon its own course; next curves forwards, and, growing gradually narrower, runs along just above the esophagus into the head, passing with the former through the brain.
The nervous system consists of a chain of ganglia and the nerves. The supra-wsophageal ganglion, or brain, occupies nearly the center of the head (Plate VII, Fig. 2, Br.), and is connected by very thick commissures with the sub-ewsophageal ganglion, which passes gradually into the cord that leads to the first thoracic ganglion. This is quite distinct, but the second and third are almost completely fused, and connect with the abdominal gauglia by a very long commiissure. In the abdomen (Plate VIII, Fig. 2) there are four nerve centers (a. g., a. g.), as is almost always the case in the Lepidoptera, lying in the third, fourth, fifth, and sixth segments respectively. The last is the largest, and is compounded of two or more ganglia fused together; the principal nerves arising from it seem to innervate the organs of reproduction.
*Burss. E. Proceedings Boat. Soc. Nat Hist., XIL 153-156.






56 REPORT, 4, UNITED STATES ENTOMOLOGICAL COMMISSION.

TERMINAL BODY SEGMENTS AND ORGANS OF REPRODUCTION.
In the state of rest the eighth and ninth segments in the abdomen of both sexes lie concealed within the seventh, the intersegmental membranes in these cases being long enough to admit of this telescoping action. The eighth segment of the male does not differ from the preceding, except in wanting the spiracles and in its smaller size. It has, however, on its under side a thick shock of long hairs or scales parted down the middle, which, when this segment is retracted within the seventh, serves to form a soft cushion between the two, although this may not be its only purpose. The brushes of hair, to be described below, borne by the ninth segment act in the same manner as a cushion between the eighth and ninth segments.
The dorsum of the latter or terminal segment is produced backwards into a slightly curved hook, often compared with the telson of the crustacea (see Plate VIII, Fig. 2, and Plate X, Figs. 1 and 3, where the hook is marked with the figure 9). This hook covers the anal opening (a.), and in some hoctuids is greatly developed. Beneath it is a chitinous finger (Fig. 3,f) which is movable, but its function is obscure.
The ventral portion of the ninth segment forms a broad trough-shaped process (Plate X, v.pr., Figs. 1-3), with upturned lateral edges, the penis lying in the bottom of the trough so formed, and hinged to each side of this segment are the "claspers," which are narrow triangular pieces with a slender, slightly incurved apex. Their exact shape will be more readily understood by referring to the lateral, dorsal, and ventral views given in Plate X, Figs. 1, 2, and 3, c left, o' right clasp.
There is still another and singular organ attached to the ninth segment. This is a sac with delicate membraneous walls thickly covered with slender, long-stalked scales (Plate IX, Fig. 3). The sac is very elastic, and may be protruded like a long finger and again retracted at will. The long hair-like scales give the organ the appearance of a brush. It is shown in various positions on Plate X, Figs. 1-3, b, the scales being removed in all the figures. This brush-sac is attached to the base of the claspers.
Morrison first called attention to similar organs in Leucarctia acrca, and states they are protruded by being filled with fluid from within. He also noticed them in Danais, Agrotis, and Euplexia. Burgess (loc.cit.) described their structure in Danais, where, however, they are not placed in the same position as in Leucarctia and the Noctuids. The retractor muscle found in Danais we have not succeeded in finding in Aletia. MUiller has also noticed these appendages, and regards them as scent organs. At all events it is probable they are organs for sexual excitation. They are not found in the female.23
The male organs of reproduction consist of a very large testis, two vasa deferentia, in each of which a tubular gland opens, a ductus ejacuM orrison, IL K. Psyche, I, 21.






INTERNAL ANATOMY OF THE MOTH. 57

latorius, and the penis. The testis is shaped like a very thick, nearly spherical, button. (Plate VIII, Fig. 2, and X, Fig. 1, Te.) It is really a compound organ composed of two testes fused together. The testes can be found in the caterpillar as separate kidney shaped organs lying close under the dorsal vessel* in the fifth abdominal segment. In both larva and imago the fifth abdominal spiracle sends a branching tracheal tree which spreads over and into the testes on each side. The vasa deferential lead from the posterior face of the testes. After a few convolutions they dilate into pod-shaped chambers, and then contract for a length of very fine tubes until reaching the point of union with the glandulw mucosw, into the basal portion of which the vasa deferentia seem to open. A short distance farther and the two vasa deferentia unite into a long, single duct, the ductus Cjaculatorius, which is of larger diameter, contracting slightly near its end, again dilating into a very muscular, gourd-shaped section (Plate X, Fig. 1), which opens into the penis.
The latter organ is a slender, chitinous tube whose top projects between the claspers and below the anus, and which lies in the the trough formed by the ventral arch of the ninth segment, as already described. It is protruded by a muscle on either side, the protractor penis, which is attached to the ninth segment. The end of one of these protractors is shown at pp in Figs. 1 and 2, of Plate X. The retractor was not found. From the tip of the penis project two prongs, which bear on their inner aspect several stout spines and some smaller teeth, as shown in Fig. 4, Plat X. These prongs seem capable of protrusion and retraction, and telescoped within the penis can be seen other chitinous processes and spines, apparently of considerable complexity, which could not be satisfactorily studied in the specimens at disposal.

FEMALE ORGANS OF REPRODUCTION.

The ovaries consist of four long slender tubes, lying in several folds on each side of the body. Their slender tips end in suspensory ligaments, all eight of which unite together immediately under the dorsal vessel. At their basal ends the ovarian tubes of each side unite into a uterine chamber (Plate IX, Fig. 4, u.), the short oviducts from which unite into a single ovduct, which passes through the eighth and ninth segment and opens between the lateral flaps of the latter beneath the anus.
Two accessory glands-colleterial or sebaceous glands, so calledwhich are concerned with secreting the egg-shell or the cement by which the moth fixes the eggs in place when laid, open into the common oviduct. The anterior gland is single; the posterior is a pair of glands with a single duct. Both consist of long cecal tubes, with pear-shaped dilations near the base, followed by another roundish dilation. (See
*See Meyer. Zeitchr. wiss. Zool. I, 182. Also H. Landos, ibid., xiii, 316.






58 REPORT' 4, UNITED STATES ENTOMOLOGICAL COMMISSION.

Plate IX, Fig. 4, a.gl.1 and a.gl.) The paired glands lie close under the rectum, and would at first sight be supposed appendages of the latter instead of belonging to the oviduct.
At the base of the eighth segment, beneath, opens the vagina (v.), the orifice of which is therefore distinct from that of the oviduct. It is a long horny canal, which leads into a very large pyriform copulatory pouch. (Plate IX, Fig. 4, c. p.) This pouch is a very remarkable organ in the Lepidoptera. Its walls are very thick, and consist of a powerful muscular layer (Fig. 7, m.), within which is an epithelial layer (sp.) or matrix which gives rise to a stout cuticula intina (ca.). This last lies in heavy folds or ridges (Fig. 5), which have a general longitudinal direction, but with various curves and anastomosing branches. It is covered with little points, or teeth, which are stouter near the base of the pouch, and similar to the cuticular spines of the larval skin described at the beginning of the chapter. Each point arises in a little field of its own, separated by various-shaped boundaries from adjoining fields. (See Fig. 6.) These fields probably correspond to the underlying cells of the matrix. Near the base of the interior of the pouch a transverse triangular flap or valve is suspended from above, very thickly covered with short teeth, like those over the rest of the pouch.
There is a deep longitudinal furrow on the top of the pouch, so that cross-sections of the latter give a Y-shaped cavity. The vagina itself has a smooth, stout cuticula. Near the base of the vagina a slender sperm-duct (s. d.) leads from the vagina into the oviduct, through which duct the spermatozoa pass from the copulatory pouch, where they are discharged into the oviduct where the eggs are to be fecundated. The sperm-duct does not expand into a spermatheca, as is often the case.
In the female, as in the male, the two terminal segments are retracted, resting within the seventh, and do not bear spiracles. The eighth segment is like the preceding in shape, but smaller, with the pocket beneath for the vaginal opening, as described. From the anterior margin, each side, a stout spur projects into the interior of the abdomen (Plate IX, Fig. 4) for the attachment of muscles to move the segment.
The dorsum of the ninth segment forms merely a membranous covering over the rectum and contains no ossified element. The sides of the segment are produced into two lobes (see Plate IX, Fig. 4), which flank the oviduct and form a short ovipositor. Anteriorly the lobes send out two spurs like those of the preceding segment, but they are not shown in the figure. Ventrally the segment terminates in a short triangular piece projecting between the lateral lobes.