INSECTS INJURJ THE HO OUS TO USEHOLD BY GLENN W. HERR1CK The RurarScieffce Ser ie s I LH, Bailey Editor THE LIBRARY OF THE UNIVERSITY OF CALIFORNIA LOS ANGELES TTbe TRural Science Series EDITED BY L. H. BAILEY HOUSEHOLD INSECTS Efje i&urai Science Series THE SOIL. King. THE SPRAYING OF PLANTS. Lodeman. MILK AND ITS PRODUCTS. Wing. Enlarged and Revised. THE FERTILITY OF THE LAND. Roberts. THE PRINCIPLES OF FRUIT-GROWING. Bailey. BUSH-FRUITS. Card. FERTILIZERS. Voorhees. THE PRINCIPLES OF AGRICULTURE. Bailey. 15th Edition, Revised. IRRIGATION AND DRAINAGE. Xing. THE FARMSTEAD. Roberts. RURAL WEALTH AND WELFARE. Fairchild. THE PRINCIPLES OF VEGETABLE-GARDENING. Bailey. FARM POULTRY. Watson. Enlarged and Revised. THE FEEDING OF ANIMALS. Jordan. THE FARMER'S BUSINESS HANDBOOK. Roberts. THE DISEASES OF ANIMALS. Mayo. THE HORSE. Roberts. How TO CHOOSE A FARM. Hunt. FORAGE CROPS. Voorhees. BACTERIA IN RELATION TO COUNTRY LIFE. Lipman. THE NURSERY-BOOK. Bailey. PLANT-BREEDING. Bailey. 4th Edition, Revised. THE FORCING-BOOK. Bailey. THE PRUNING-BOOK. Bailey. FRUIT-GROWING IN ARID REGIONS. Paddock and Whipple. RURAL HYGIENE. Ogden. DRY-FARMING. Widtsoe. LAW FOR THE AMERICAN FARMER. Green. FARM BOYS AND GIRLS. McKeever. THE TRAINING AND BREAKING OF HORSES. Harper. SHEEP-FARMING IN NORTH AMERICA. Craig. COOPERATION IN AGRICULTURE. Powell. THE FARM WOODLOT. Cheyney and Wentling. HOUSEHOLD INSECTS. Herrick. INSECTS INJURIOUS TO THE HOUSEHOLD AND ANNOYING TO MAN BY GLENN W. HERRICK PROFESSOR OF ECONOMIC ENTOMOLOGY IN THE NEW YORK STATE COLLEGE OF AGRICULTURE AT CORNELL UNIVERSITY Nefa gorfe THE MACMILLAN COMPANY 1914 AU right* reserved COPYRIGHT, 1914, BT THE MACMILLAN COMPANY. Set up and electrotyped. Published October, 1914. XottoooH ISrtss J. 8. Cashing Co. —Berwick & Smith Co. Norwood, Mass., U.S.A. lture INTRODUCTION SOME one has remarked in a rather facetious vein that, from a zoological standpoint, the present age may be called the age of insects. On second thought, the remark holds more reason than might appear at first sight. We are especially impressed with the impor- tance of the relation to man of these tiny, but multitu- dinous, forms of life when we recall that the species of insects outnumber the species of all other animals com- bined ; that the insect pests in this country alone cause a loss of over a billion dollars annually ; that several hundred trained men in the United States are giving their entire time to a study of these pests ; and that thousands of letters are sent each year to our govern- ment agencies, requesting information regarding insects and means of fighting them. Until within the last few years the economic importance of insects has been at- tributed to their indirect injuries to man through attacks on the things that he produces. Suddenly, almost within the last decade, insects have assumed an entirely new and exceedingly important significance through knowledge of their direct injuries to man himself. Since the epoch-making discoveries were made that mosquitoes carry malaria and yellow fever, insects, es- pecially those frequenting the household, have assumed a most unexpected importance. The hum of the mos- quito and the buzz of the house-fly have become fraught with an entirely new significance. Even the dog and 833185 Vi INTRODUCTION • the cat, with their burdens of fleas, have taken on a new aspect and appeal to us from an entirely new viewpoint. The kitchen drain, the open cesspool and closet, the barnyard manure pile, the horse stable, and the hog pen present entirely new problems to the occupants of the farm home through the insects that originate in them. One neglected manure pile can furnish enough house-flies to overrun several households all the summer through. An open kitchen drain can afford breeding- places for enough mosquitoes to change pleasant summer evenings into hours of torment and displeasure. The present work is not intended as a treatise on the relation of insects to disease. The author's colleagues are now at work on a thorough and extended discussion of that phase of the subject. In the following pages, the writer devotes the principal part of the discussion to the habits, injuries, and control of insects simply as pests of the household and of man, contenting himself with a brief summary of the relation of insects to disease. It is hardly to be expected that so brief a work will include all of the insect pests that may invade the household ; but an attempt has been made to discuss, at least, the most important ones with which our present knowledge makes us more or less familiar. The erroneous ideas and unnecessary fears prevalent regarding the poisonous nature of certain insects and their near relatives and the interest evinced in this matter have seemed to warrant the addition of a chapter on this subject. In this discussion, the author has at- tempted to state the simple truth and to clear away, as far as existing knowledge makes it possible, the hazy and almost superstitious notions regarding the venomous qualities of these small animals. INTRODUCTION vii The book has been written particularly for the house- keeper and for those who desire to obtain information regarding household pests and practical methods of controlling them. As few technical terms as possible have been used. . Nevertheless, painstaking efforts have been made toward accuracy of statement. To make the work of value to the student, references to literature have been given and the lack of knowledge regarding the life histories and habits of many of these common pests has been pointed out with the hope of stimulating investigation. The author has drawn freely on all available sources of information and has often quoted extensively from various writers. Most of the illustrations are original. They have been drawn from actual specimens principally by Miss Anna C. Stryke, Miss Catherine Kephart, and Mr. John Eyer. To these the author is greatly in- debted for their careful and accurate delineation. Whenever it has seemed more advantageous, figures have been copied from various sources but full credit has always been given. The writer is also under deep obligation to his wife, Nannie B. Herrick, who has read the manuscript and proof and has made many helpful suggestions and constructive criticisms. GLENN W. HERRICK. ITHACA, NEW YORK. CONTENTS :HAPTEK PAGES I. THE HOUSE-FLY 1-34 II. FLIES, OTHER THAN. THE HOUSE-FLY, THAT FREQUENT HOUSES 35-53 III. MOSQUITOES, THEIR HABITS AND DISEASE RELATIONS 54-83 IV. METHODS OF DESTROYING AND REPELLING MOSQUITOES 84-107 V. THE COMMON BEDBUG 108-123 VI. COCKROACHES 124-143 VII. FLEAS 144-163 VIII. ANTS, THEIR ACTIVITIES AND INVASIONS OF THE HOUSEHOLD 164-188 IX. INSECTS INJURIOUS TO CLOTHES AND CAR- PETS 189-226 X. INSECTS INJURIOUS TO CEREALS AND PRE- SERVED FRUITS 227-271 XI. INSECTS INJURIOUS TO MEATS, CHEESE, AND CONDIMENTS 272-299 XII. SOME HUMAN PARASITES 300-316 XIII. SOME ANNOYING PESTS OF MAN . . . 317-346 XIV. SOME TROUBLESOME INVADERS OF THE HOUSE- HOLD 347-385 ix X CONTENTS CHAPTEE PAGES XV. SOME WOOD-BORING INSECTS AND THEIR RELATIVES 386-397 XVI. POISONOUS INSECTS AND THEIR RELATIVES . 398-440 XVII. THE USE OF GASES AGAINST HOUSEHOLD INSECTS 441-461 INDEX . 463-470 LIST OF ILLUSTRATIONS FIGUBE PAOB 1. The adult house-fly. ( x 5.) . 1 2. Maggot of house-fly. ( x 3£.) 4 3. Puparium of house-fly. ( x 5.) 5 4. Foot of house-fly, showing pulvilli, enlarged ... 7 5. Plate of gelatine, showing colonies of bacteria in foot- prints of fly. (x 1.) After Underwood . . . 8 6. Head and proboscis of house-fly. ( x 20.) ... 9 7. Bin for holding manure. After Herms .... 22 8. Hodge's trap for garbage can. After Howard . . 25 9. A large fly trap. After Bull '26 10. End of trap, showing hooks. After Bull ... 27 11. Cross-section of trap. After Bull 27 12. Wing of the lesser house-fly. ( x 10.) .... 36 13. Wing of house-fly. ( x 10.) 36 14. Wing of stable-fly (Muscina stabulans). (x8.) . . 37 15. The cluster-fly. ( x 2£.) 39 16. Head and proboscis of the biting house-fly. ( x 8.) . 42 17. Biting house-fly (Stomoxys calcitrans). (x3^.) . . 42 18. The stable-fly (Muscina slabulans) . ( x 3.) . . .46 19. The blow-fly. ( x 2.) 49 20. Life history of a house mosquito. ( x 3.) After Howard 56 21. Egg mass of the house mosquito, (x 5.) . . . 57 22. Pupa of Culex, enlarged .58 23. Head of female, left; male, right, (x 8.) . . .59 24. Anopheles quadrimaculatus . (x7.) . . . .61 25. Larva of Anopheles punctipennis, enlarged ... 62 26. Anopheles punctipennis. ( X 7.) . • . . .64 27. Head of female Culex, left; female Anopheles, right. (x 8.) 65 xi Xii LIST OF ILLUSTRATIONS FIGTTBK PAGE 28. The yellow fever mosquito. ( x 7.) . . . .67 29. Trichinella spiralis embedded in human muscle, much enlarged 73 30. Roach or golden shiner. After Jordan .... 87 31. Top-minnow. ( x 1|.) After Jordan and Evermann . 88 32. Spraying a ditch for mosquitoes with a knapsack sprayer 91 33. Screen covering whole window 99 34. Screen over lower half of window 99 35. Under side of head of bedbug showing the beak, enlarged 109 36. Nymph of a species of Aradus, much enlarged . .116 37. Egg-case of croton-bug. ( x 3.) . . . . . 132 38. American cockroach. ( x 1.) 135 39. Oriental cockroach. ( x f .) 136 40. Australian roach, (x 1J.) 137 41. Cross-section of a roach trap . ... . . . 140 42. Tin box trap for roaches 140 43. Human flea, much enlarged 147 44. Cat and dog flea, much enlarged 147 45. Egg of flea. ( x 38.) 150 46. Larva of a flea, above; cocoon, below, much enlarged. After Howard 151 47. Interior of an ant's nest. From Wheeler's " Ants " . 167 48. The red ant. ( x 20.) 174 49. The small black ant. ( x 14.) . . . . . .176 50. The large black carpenter ant, enlarged .... 178 51. The queen Argentine ant, enlarged. After Woodworth 183 52. Case-making clothes moth. ( x 4.) . . • . .192 53. Case of the case-making clothes moth ( x 3.) . . 193 54. Webbing clothes moth. (x4.) 195 55. Egg of the webbing clothes moth. ( x 25.) . . .196 56. Larva of the webbing clothes moth, (x 6.) . . . 197 57. Tapestry moth. (x3.) 197 58. The "Buffalo bug" (carpet beetle). (x9.) . . . 204 59. A common lady-bird. ( x 13.) 205 60. Cast skin of larva of "Buffalo moth." ( x 6.) . . 206 61. Black carpet beetle. ( x 9.) 210 LIST OF ILLUSTRATIONS xiii FIGURE PAGE 62. Larva of the black carpet beetle. ( x 5.) . . . 211 63. Pupa of the black carpet beetle, dorsal and ventral view. (x 9.) 212 64. The fish-moth. ( x 2.) 215 65. The domestic fish-moth. (xl£.) After Marlatt . . 219 66. The domestic cricket, (xlj.) After Marlatt. . . 224 67. The Cadelle. ( x 4.) 232 68. Larva of the Cadelle. ( x 3.) 233 69. Section of bin showing holes in the wood made by the larva of the Cadelle 234 70. The saw-toothed grain-beetle. ( x 20.) .... 237 71. Larva of saw-toothed grain-beetle, enlarged . . . 237 72. The Angoumois grain-moth. ( x 3.) . . . . 239 73. Ear of popcorn infested with larvae of the Angoumois grain-moth 240 74. Egg of Angoumois grain-moth, enlarged .... 240 75. Larva of Angoumois grain-moth, enlarged . . . 241 76. Pupa of the Angoumois grain-moth, enlarged . . 241 77. The confused flour-beetle. ( x 12.) .... 248 78. Larva of the Indian-meal moth, enlarged . . . 254 79. The meal snout-moth and larva. ( x 2£.) . . . 257 80. ' The granary weevil. ( x 17.) 259 81. The rice weevil. ( x 7.) 261 82. Larva of the rice weevil. ( x 10.) 262 83. Pupa of the rice weevil. ( x 10.) 263 84. A fruit-fly (D. ampelophila). ( x 10.) . . . .265 85. Pupa of a fruit-fly, enlarged 266 86. Bean weevil. (x8.) 270 87. Larder beetle. ( x 4.) 273 88. Larva of the larder beetle. ( x 3.) 274 89. Red-legged ham beetle. ( x 8.) 277 90. Larva of the red-legged ham beetle, enlarged . . . 278 91. A common cheese mite (T. lonyior). (x 60.) After Canestrini 281 92. Hypopus of cheese mite, much enlarged. After Banks 282 93. A cheese mite (T.farince). (x 80.) After Banks . 284 xiv LIST OF ILLUSTRATIONS FIGURE PAGE 94. Sugar mite (G. robustus). (x50.) After Banks . 286 95. Tarsi I, IV, and hairs, h, from T. longior, enlarged. After Banks 287 96. The parent fly of a cheese skipper. (x9.) . . . 288 97. Cheese skipper, maggot of P. casei. ( x 5.) . . . 290 98. Pupa of cheese skipper, enlarged 290 99. Cigarette beetle. ( x 20.) 293 100. Larva of cigarette beetle. ( x 20.) . . . .294 101. Drug-store beetle. ( x 24.) 295 102. Larva of drug-store beetle. ( x 20.) .... 297 103. Itch mite, female. ( x 85.) 302 104. Itch mite, male. ( x 125.) 303 105. Burrows of the itch mite beneath the skin, diagrammatic 304 106. Head louse. ( x 13.) 310 107. Body* louse. ( x 20.) 312 108. Crab louse. ( x 20.) 314 109. Adult of harvest mite (T. holosericeum). ( x 20.) After Railliet 318 110. Young of harvest mite. ( x 60.) After Railliet . 321 111. Yellow-jacket. ( x 3.) 326 112. Bald-faced hornet, (x 2£.) 326 113. A punkie (C. stellifer), enlarged. After Pratt . . 331 114. A punkie (C. guttipennis), enlarged. After Pratt . 332 115. Larva and pupa of a punkie (C. guttipennis), enlarged . After Pratt . 333 116. A black-fly (S. pictipes). (x 10.) 341 117. Larva of the black-fly (S. pictipes). ( x 3.) . . . 342 118. Pupa of a black-fly (S. pictipes). (x6.)' . . .343 119. The female mite, much enlarged. After Banks . . 349 120. The female mite when full of eggs, enlarged. After Banks 350 121. The male mite, enlarged. After Banks . . .351 122. The clover mite, adult, enlarged. After Marlatt . . 353 123. A young clover mite, enlarged. After Marlatt . . 354 124. The house centipede, (x 1.) . . . ... 357 125. A scorpion, (xf.) 361 LIST OF ILLUSTRATIONS XV PAGE 126. A queen termite, (xl.) ...... 365 127. A soldier termite. ( x 13.) ...... 366 128. Winged male termite, enlarged ..... 367 129. A worker termite. ( x 9.) ...... 368 130. The American spring-tail, enlarged. After Marlatt . 378 131. The American spring-tail, under side of the body, en- larged. After Marlatt ...... 378 132. The common book -louse, enlarged .... 380 133. A powder-post beetle (Z. linear is), enlarged . . . 387 134. The death-watch beetle, enlarged ..... 389 135. The white-marked spider-beetle, enlarged . . . 393 136. Chelicera of a spider ; p, poison gland ; d, duct; 0, open- ing at tip of fang ; /, fang, enlarged . . . 399 137. Hour-glass spider, dorsal view. ( x 2|.) . . . 403 138. Hour-glass spider, ventral view. (x4£.) . .. 404 139. The southern cattle-tick. ( x 4£.) ..... 407 140. A solpugid. After Putnam ...... 409 141. Centipede from Texas, much reduced .... 412 142. A dragon-fly. ( x 1.) ....... 415 143. An earwig. (x2.) ....... 416 144. An electric light bug (Belostoma) . (xl.) . . . 417 145. The cannibal bug (R. personatus). ( x 2.) . . . 419 146. The blood-sucking cone-nose. ( x 3.) . . . .423 147. Screw worm fly. ( x 3^.) . . ... . .425 148. The buck moth (H.maia). (xl.) . . . .429 149. Eggs of the buck moth, (xl.) • • • .430 150. Poisonous hairs (P) and ordinary hairs (R) of the brown-tail moth caterpillars ..... 434 151. Materials used in fumigation . • . . . . 444 152. A room " strung " for fumigation ..... 446 LIST OF PLATES FACING PAGE Plate I. Eggs of house-fly, above ( x 4), Photo, by Knight ; properly screened porch below, Photo, by MacGillivray . 30 Plate II. Cockroach, croton-bug with egg-case ( x 1) ; trap for cockroaches, Photos, by Slingerland ; bedbug, below, much enlarged, Photo, by author 110 Plate III. Beetle of darker meal-worm ( x 3) ; and pupa ( x 2£) ; pupae and larva of meal-worm ( x 1), Photos, by Knight; yeast cake injured by drug-store beetle, Photo, by author 228 Plate IV. Indian-meal moth above, enlarged by Bishop; Mediterranean flour-moth ( x 3) by Bishop ; eggs ( x 5) and pupae of Mediterranean flour-moth, Photos, by K night 244 Plate V. Blisters on leg caused by redbugs, enlarged, Photo. by Bradley 322 Plate VI. Book injured by termites, above, Photo, by author ; nest of termites in South Africa, below, Photo, by Gunn 364 Plate VII. Tarantula, above, Photo, by Crosby ; chicken ticks, Photo, by author; and brown-tail moths, below, Photo, by Slingerland 402 Plate VIII. Caterpillar of buck moth above, Photo, by Ilg ; saddle-back caterpillar in middle, Photo, by Slingerland ; larvae of flannel moth, Photo, by Slingerland ; and of io moth, below, Photo, by Knight 428 xvii HOUSEHOLD INSECTS CHAPTER I THE HOUSE-FLY Musca domestica THERE are no household insect pests more annoying, on the whole, than house-flies. They are present from early spring to late fall, even remaining far into the winter. They are trouble- some in kitchens and dining- rooms because of their abun- dance, their proneness to get into food, and their gener- ally filthy habits. Until within comparatively recent years the house-fly (Fig. 1) has been generally regarded as somewhat of a scavenger and has been considered of value to humanity because of its aid in the removal of wastes that are a menace to human welfare. The eggs of the house-fly are often deposited on decaying vegetable FIG. 1. — The adult house-fly. (X5.) 2 HOUSEHOLD INSECTS matters that are allowed to accumulate in the vicinity of human habitations and the maggots that hatch from the eggs live on this decaying matter and aid in destroy- ing it. Thus it must be conceded, perhaps, that house- flies do assist somewhat in the removal of foul and dangerous waste matters and, to this extent, are of benefit. On the other hand, it has been conclusively shown that this modicum of benefit is greatly over- balanced by their role in disseminating dangerous dis- eases. It has been shown that house-flies carry the germs of cholera, typhoid fever, cholera infantum, and tropical dysentery, on their feet, legs, and bodies and in their digestive tracts. There can be no doubt of the responsibility of the house-fly for much sickness and many deaths. A COMMON SOURCE OF HOUSE-FLIES In the summer of 1910, two large piles of horse ma- nure were drawn and placed in a field about twenty rods south of the building in which the office of the author is located and on the same side. During the months of July and August the flies were so abundant in the build- ing and especially in my office that screens had to be used as a protection against the dreadful annoyance of these pests. On investigation, the piles were found to be teeming with maggots of the house-fly. In seven ounces of the manure, taken from the smaller pile, 458 maggots of various sizes were actually counted. Many of the smaller ones must have escaped notice. The seven ounces of manure was a seething mass of maggots, showing what a tremendous number of flies the two piles of manure could have furnished if they had been equally infested all THE HOUSE-FLY 3 through the surface layers. Fortunately they were not. It was only in the moist, warm portions of the piles near the surface that maggots were present. But with these conditions enough flies were bred in the two piles of manure to stock the rooms of a very large building. Apropos of the possibilities of manure in the produc- tion of house-flies, L. O. Howard gives even more surprising figures. He took a quarter of a pound of horse manure, well infested, and found within it 160 maggots and 146 puparia which would produce about 1200 flies to a pound of manure. Again, during September, the manure that had been allowed to accumulate for several months was removed from a certain large cowshed at the old University barns. The wagons were backed under the shed and loaded. When drawn out they had to pass over a plank twelve inches wide that served as a threshold of the double doors. After the work had been going on some time, W. A. Riley gathered the puparia that had accumu- lated on one square foot of this plank. By weighing the whole mass and a known number of the puparia, he was able to determine that the square foot of surface had yielded 7000 puparia. In a subsequent examination, the plank was found, for its whole length, black with them, and the remaining manure on the floor of the shed was full of the dark brown puparia. THE LIFE HISTORY OF THE HOUSE-FLY The house-fly, like its remote cousin, the mosquito, has four distinct stages in its life history, egg, larva or " mag- got," pupa, and adult. The house-fly, in all of its phases 4 HOUSEHOLD INSECTS and instincts, seems to be a lover of filth. Its eggs are usually laid in manure, preferably in horse manure, at least whenever this medium can be found. Sometimes they are laid on cow manure and often on human excre- ment, especially in open closets, and on other decaying animal and vegetable material. A female fly may deposit 120 to 150 eggs at a time and as she has been observed to make four deposits we must conclude that a single fly is capable of laying at least 600 eggs. This will account, in a measure, for the enormous number of these insects. The egg is a small, white object about one-twentieth of an inch long and resembles in shape a grain of wheat, except that it is more pointed. They are laid more or less in clusters (Plate I) and hatch in from FIG. 2. -Maggot of house- eight to twenty-four hours or fly. (x3i) longer, depending on the tem- perature. The maggot is whitish in color, pointed at the head end, blunt at the opposite end and about one-third of an inch in length when mature (Fig. 2). It is quite active and can crawl with considerable facility. It grows rapidly, molts three times,1 and reaches maturity in five to seven days under favorable conditions. With the third and .last molt the larva transforms to a pupa. The pupa is inclosed in the last cast skin of the maggot. This skin soon turns dark brown and becomes hard and dry, thus affording a protective case for the pupa, known as a puparium (Fig. 3). The pupa rests quietly for five to seven days or longer, at the end of which time its enveloping case breaks open and the adult fly comes forth. 1 If the casting of the last skin that serves as a puparium is counted. THE HOUSE-FLY 5 Our observations indicate that house-flies frequently pass the winter in the pupal stage. We are also of the opinion that adult flies are able to survive the winter. The length of time required for a generation of flies to mature varies and will depend upon the temperature, amount of food available, and other factors. For example, in Massachusetts, it may take about fourteen days for a generation of flies to mature, while in the latitude of Washington, D.C., ten days may be sufficient. But it takes the flies several days after they issue to become sexually mature and ready to lay eggs. In Massachu- setts, then, there might be time, during a favorable season, for seven or eight complete generations, while in the latitude of Washington there would be time for ten or twelve Fl°- 3- — Puparium of ,. n i_ ji r house-fly. (X 5.) generations. One can hardly realize the enormous numbers that such rapid development is capable of producing. Inside of two months, one female fly can give rise to many millions of progeny. For the purpose of illustration, we will assume that a female fly lays 100 eggs. If these hatch and all the larvae come to maturity, about one-half will probably be males and the other half females. Then at the end of the first genera- tion there will be fifty egg-laying females. At this rate, at the end of the eighth generation there would be pro- duced about 1,875,000,000,000 adults. Of course, in nature, a very large part of these would die and never reach maturity, so that actually one female would prob- ably never produce such an enormous number of individuals. However, under normal conditions tre- mendous numbers are produced. HOUSEHOLD INSECTS BREEDING PLACES FOR FLIES Without doubt, house-flies prefer piles of horse manure whenever these can be found. This has been shown by many observers. Next to horse manure, flies apparently prefer human excrement. At least, open closets in the back streets of cities have been shown to be one of the main sources of house-flies in such localities, especially in those regions in which there are few or no horse stables. Moreover, Howard has shown that the larvae of house- flies are often found in chance droppings of human feces in back allies, yards, and so on. We would emphasize the fact that the most dangerous breeding places for flies are in open closets; for in these places the germs of typhoid fever, dysentery, and other enteric diseases are present in great abundance. House-flies will also breed in cow manure especially when moist enough. Piles of stable manure containing rotting straw or barnyard refuse are favorable breeding places. Manure, bedding, and filth of pig-pens breed large numbers of flies ; even the refuse of poultry houses, if composed in considerable part of rotting bedding, may contain maggots. The decaying and fermenting garbage from kitchens, if allowed to stand long enough in barrels or cans, may become breeding places for flies, although it would seem that the stable fly, Muscina stabulans, is the more common fly in such situations. Forbes' assistants bred 267 house-flies from carrion in the streets, which runs contrary to former ideas concern- ing carrion and house-flies. It is probably safe to say that house-flies will breed in almost any vegetable matter that lies long enough to ferment and decay. THE HOUSE-FLY THE ADULT FLY The adult fly is about one-fourth of an inch in length and has two thin membranous wings, the fifth longitudinal veins of which turn abruptly upward near the ends (Fig. 1). The dorsal side of the thorax is dusty gray in color and has four dark, longitudinal stripes. The legs and the body are covered with many hairs and bristles, among which great quantities of germs are easily entangled and carried from place to place. Moreover, each one of the six feet is furnished with two sticky pads called pulvilli (Fig. 4). Each pad, or pulvillus, is thickly beset with tiny hairs, which secrete minute drops of a sticky liquid that literally sticks the fly to the ceiling upon which it is walking. Unfortunately, these sticky hairs, in addition to enabling the fly to walk upside down, form ideal organs for picking up all sorts of FIG. 4. — Foot of bacteria from the filthy materials upon which the fly walks. Thus we see the house-fly is fitted in many ways for gathering and carry- ing germs. In fact, it cannot help but gather bacteria from the various things upon which it alights and then distribute them far and wide, for it wipes its feet upon everything it touches. The relation of the fly to the germs that it carries is purely a mechanical one. It has been shown repeatedly that house-flies do carry multi- tudes of bacteria. In Fig. 5 is shown a plate of gelatine house-fly, showing pulvilli, enlarged. 8 HOUSEHOLD INSECTS over which a fly was allowed to walk. In every foot- print there is a white colony of bacteria with millions of individuals. Esten and Mason examined 414 flies from different sources and found that the number of bacteria carried by. each one varied from 550 to 6,600,000, with an average FIG. 5. — Plate of gelatine, showing colonies of bacteria in footprints of fly. (X 1.) for each fly of nearly one and one-fourth millions. They also found that those flies caught in swill-barrels, pig-pens, and similar places carried the most bacteria and the most objectionable kinds of bacteria. The mouth-parts of the house-fly are very complicated but, in general, they constitute a short proboscis fitted for sucking but not for piercing. The house-fly cannot THE HOUSE-FLY 9 "bite." The proboscis (Fig. 6) can be protruded and retracted to a certain extent. Roughly, the proboscis consists of two parts, a part nearest the head that bears two short curved appendages, and a longer part farthest from the head that bears two lobe-like appendages called the oral lobes. Each lobe bears on its under surface many trans- verse ridges called false tracheae (pseudotrachese) . These lobes are rasping organs. Each lobe reminds one of an old-fashioned shoe float formerly seen in stores and used for removing the ends of wooden pegs that projected through the soles in the inside of a shoe. When feeding on fluid substances the fly simply applies the oral lobes to the material and sucks it up. When feeding upon solid substances FIG. the action is quite different. If such a substance as sugar is eaten, for example, it is first moistened and dissolved by saliva from the mouth of the fly before it is sucked up. The oral lobes also serve to rasp the material and break it down. Graham-Smith watched a fly sucking a mass of sputum that had apparently dried and hardened. The insect seemed to moisten the layer of sputum by sending out saliva through its proboscis and sucking the fluid in and out until the layer was liquefied and could be drawn up into the mouth. • Head and proboscis of house-fly. (X 20.) 10 HOUSEHOLD INSECTS HOW FAR CAN THE ADULT FLY ? The question of how far this insect will fly from its breeding place has an important bearing upon methods of fighting it. Moreover, the area that it can cover in a neighborhood has an important bearing upon its dangers as a disease-germ-carrying instrument. It is held by observers, in general, that house-flies, under normal con- ditions, do not fly far. However, when aided by winds they may go considerable distances. Arnold, of the Monsall Fever Hospital in Manchester, captured 300 flies and marked them with a spot of white enamel on the back so that he could identify them. He liberated these in fine weather and during the next five days captured 5 out of the 300 in traps, all within 30 to 190 yards from the point of liberation. Hewitt says he has seen them flying at a height of 80 feet and remarks that this would greatly facilitate their carriage by winds. In an experiment by Copeman, Howlett, and Merriman, three English investigators, on the range of flight of flies, they recovered marked specimens at distances varying from 400 to 1408 yards and, in one case at least, at a distance of 1700 yards. This indicates a flight of nearly a mile. It shows that the breeding places within a mile of a given building must be abolished if the flies are ex- terminated. C. F. Hodge has found house-flies very numerous on the cribs of the Cleveland waterworks six miles out in Lake Erie. These flies could not possibly have bred on the cribs and the only conclusion is "that the flies are blown at least six miles off shore." THE HOUSE-FLY ENEMIES OF THE HOUSE-FLY The house-fly has a goodly number of enemies, some of them members of the plant world, but most of them belonging to the animal kingdom. These enemies, how- ever, do not seem to succeed in reducing the num- bers of the house-fly to any great extent. Of course, it is impossible to say how many house-flies there might be if none of its enemies existed. It is a common thing to find dead house-flies on window panes in the fall surrounded by a whitish ring. This ring is caused by the minute white spores of a fungus that lived within the body of the fly, finally causing its death. There are, at least, three species of these minute low plants or fungi that have been found to attack the house- fly. Certain mites are often found attached to the bodies of house-flies. It is certain that some of these, at least, are simply clinging to the fly as a method of transportation from one place to another. They undoubtedly lie in wait for the fly and when opportunity offers seize hold and are carried to a supply of food, where they drop off. It is possible that other species of these mites feed upon their host, but very little of definite information is at hand con- cerning this point. Of course, spiders, when allowed to build their webs and establish themselves in rooms, will catch and kill many flies. Hornets are more or less effective fly catchers. The English Entomologist, Westwood, writing in 1840, quotes from St. John's "Letters to an American Farmer" to the effect that "The Americans, aware of their [hornets] 12 HOUSEHOLD INSECTS service in destroying flies, sometimes suspend a hornet's nest in their parlors." Again, in 1869, Benjamin D. Walsh, an American Entomologist, writes that "some persons in America have turned this insect devouring propensity of the hornets to good purpose by suspending one of their nests in a house much infested by the common house-fly. In such a situation we have been told that they soon make a clearance of the obnoxious flies ; and so long as you do not meddle with them they will not meddle with you." It has never been the author's good fortune to know any one personally who has used this unique method of destroying house-flies. Under ordinary circumstances we believe the good housekeeper would rather take her chances of happiness among the house- flies than with a good big nest of hornets as a kitchen companion. There are several minute hymenopterous parasites of the house-fly. Some of these are parasitic on the larvae and some upon the puparia. It is probable that in certain instances some of these parasites are numerous enough to destroy many flies. However, much more remains to be learned regarding the habits and destructiveness of these enemies of the fly. A. A. Girault and G. E. Sanders of the University of Illinois have given a good deal of attention to the parasites of the house-fly. Many of their observations have been published in the entomological magazine, Psyche, within the last two or three years. In one instance, at least, they found a certain parasite so abundant that it destroyed as high as ninety per cent of its host. One could wish that this enemy of the house-fly occurred more fre- quently and were more widely distributed. THE HOUSE-FLY 13 THE RELATION OF THE HOUSE-FLY TO DISEASE Notes of suspicion have been sounded against the house- fly by far-seeing physicians for many years, but nothing definite was proven against this insect until comparatively recent times. It has now been definitely proven that house-flies can and do carry, both externally and inter- nally, certain disease producing germs. For example, it has been shown by several observers that the bacilli of typhoid fever may be carried on the feet, legs, bodies, and in the alimentary canals of flies. Moreover, the bacilli pass through the alimentary tract and are voided in the "specks" in a virulent condition. The typhoid bacillus has been recovered from flies caught in undrained privies. The bacillus of cholera has also been found in great numbers on the bodies of flies and has been found in fly "specks" within 17 hours after the insects have been fed upon cholera infected material and the bacilli have persisted in the "specks" for several days. Moreover, flies infested with these germs have been shown to carry them to milk. It is also held that the house-fly may carry the tuber- culosis bacillus and deposit it on food. Several experi- menters have found the bacillus in the intestines and ex- crement of flies that have been fed on the sputum of tuberculous patients. There is evidently grave danger of infection through the agency of house-flies. Every one has noted the avidity with which flies seem to feed on expectorated saliva. House-flies are charged with the conveyance and dis- tribution of the germs of infantile diarrheal diseases. Jackson showed that the mortality of bottle-fed infants 14 HOUSEHOLD INSECTS in proportion to those feeding at the breasts was as 25 to 1 in New York City. He feels sure that the house-fly is responsible for a large part of this mortality among bottle-fed infants, due to the infection of the milk by the flies with the germs of infantile diarrhea, and the like. There seems a possibility that the house-fly may convey the plague bacillus from infected rats or human beings to other individuals. The bacilli of leprosy have been found in the alimentary canals and feces of flies after they have been allowed to feed on leprous sores. Whether these bacilli, if lodged by the fly on the person of an un- infected individual, would enter the system of that in- dividual and produce the disease is not known. At all events, one would not care to have a fly carrying these bacilli alight on one's food or person. Anthrax bacilli are also carried about by flies, and Howe, according to Howard, has shown that the purulent con- junctivitis of the Egyptians is spread by the house-fly. House-flies are especially dangerous as agents of the dis- semination of disease germs because they are fond of all kinds of human foods, both liquid and solid, and, moreover, are very restless, active insects, traveling quite extensively and flitting from place to place with considerable rapidity. "In the course of a few moments a single fly may crawl over human or other excrement, sip from a glass of milk or water, and merrily chase across a dish of mashed potatoes, or other human food. It may visit a dead and decaying animal, or sport about the mouth of a reeking sewer, and in the next five or ten minutes sip from the edge of a glass of jelly or alight in the sugar bowl." As an English author wrote many years ago, the house-flies become a great nuisance "both from their numbers and THE HOUSE-FLY 15 the pertinacious curiosity with which every individual of the race seems resolved, for its own satisfaction, to taste, see, and touch every object around it." As a result of this restless characteristic of the house- fly, it often plays a prominent part in the contamination of milk. Unfortunately, milk is a favorable medium for the growth and multiplication of bacteria and it is, there- fore, easily contaminated. We have already pointed out that the body and feet of the fly are admirably fitted for carrying bacilli ; and that the bodies of flies are usually teeming with myriads of these microscopic plants. More- over, it is easy, in fact almost inevitable, for flies to fall into open pails and cans of milk whenever the latter are accessible to these roving insects. If a fly bearing typhoid fever bacilli should fall into a pail of milk, the contagion might easily be spread all along the route of the milkman. Undoubtedly, such instances have occurred, as shown by the following case quoted by Hewitt from Taylor (Colorado State Board of Health). " In the city of Denver we had a very sad as well as a plain demonstration of the transmission of typhoid fever by flies and milk. Early in August of this year the wife of a dairyman was taken with typhoid fever, remaining at home about three weeks before the removal to the hospital, August 28. During the first two weeks of September we received reports of numerous cases of typhoid fever in the northern portion of Denver, and upon investigation found that all these cases had been securing their milk from this dairy. An inspection of the dairy was then made, and in addition to learning of the illness of the dairyman's wife, we also found the dairyman himself suffering with a mild case of typhoid fever, but still up and delivering milk. The 16 HOUSEHOLD INSECTS water supply of the dairy was fairly good. However, we found that the stools of both the wife and husband had been deposited in an open privy vault located 35 feet from the milk-house, which was unscreened and open to flies. The gelatine cultures exposed for 30 minutes in the rear of the privy vault and in the milk-house among the milk-cans gave numerous colonies of typhoid bacilli, as well as colon bacilli and the ordinary germ-life. The source of infection in the dairyman's wife's case is un- known, but I am positive that in all the cases that occurred on this milk route the infection was due to bacilli carried from this vault by flies and deposited upon the milk-cans, separator, and utensils in the milk-house, thereby con- taminating the milk. The dairyman supplied milk to 143 customers. Fifty-five cases of typhoid fever occurred and three deaths resulted therefrom." THE NATURE OF TYPHOID FEVER AND ITS RELATION TO THE HOUSE-FLY The relation of the house-fly to typhoid fever is con- sidered the most important phase of the disease-germ- carrying powers of this insect. In order to understand and appreciate this relation clearly, something of the nature of the fever and of the typhoid bacillus should be known. Typhoid fever is a so-called enteric disease. That is, it is caused by a bacillus or germ that enters and lives within the intestines of the affected individual, causing liberations of these organs. The bacillus affects other organs than the intestines, for example, the spleen, and is often found in the kidneys, liver, lungs, and even in the brain. Its presence, together with a poison that it ex- THE HOUSE-FLY 17 cretes, produces the conditions that give rise to the char- acteristic symptoms of typhoid fever, namely, an increas- ing and fluctuating temperature, rose rash over the abdomen, diarrhea or constipation, and occasionally hemorrhages of the intestines. The peculiar and vitally important thing about the bacillus causing the disease is, that it may be present in the alimentary canal of a human being some time before the individual becomes ill and may remain long after the patient has entirely recovered. Moreover, the bacilli, when present in an individual, may be given off in the feces and in the urine. Thus, an individual may be giving off these bacilli of typhoid fever days before taking to the bed, and weeks or months or even years, in the case of a "walking typhoid" patient, after recovery. If the excreta or urine containing these bacilli are deposited where they are accessible to flies, for instance in open privies, the chances are high that the bacilli will be carried on the bodies of these insects back to our kitchens and dining-rooms and be deposited on our food. During the Spanish-American War, flies were traced by their whitened feet, from the lime-sprinkled, open latrines, or privies, to the dining tables of the soldiers in camp. It makes one shudder to think of the thousands of open closets in the towns of the United States to which flies have access and in which they breed and from which they may come direct to our kitchens and dining-rooms. CHRONIC CARRIERS As stated in the foregoing, it has been known for some time that the bacilli of typhoid might be given off before 18 HOUSEHOLD INSECTS the patient was brought to bed and several days, perhaps, after apparent recovery. But it is only within com- paratively recent years that the "chronic carrier" has become recognized. Howard gives many instances of this type of affected individual, among the more notable of which are the two following : " The first case here to receive general notice was that of 'Typhoid Mary,' an Irish cook, who was discovered by Dr. George A. Soper of New York. She had been cook with a family on Long Island and during the summer of 1906 several cases of typhoid occurred. The writer was consulted, and advised that Doctor Soper be called in to make a thorough investigation. The results of Doctor Soper's search were most interesting. After studying every possible source with absolutely negative results, the proper examinations were begun, and it was dis- covered that Mary, the cook, was a chronic carrier. Her past history was looked into, and it was found that for several years there had been typhoid cases in nearly every family who had engaged her. She was immedi- ately isolated and kept in custody three years. Then she was released, promising never again to engage as cook and to report at frequent intervals. She returned after four months, saying that she could get no work and was placed by the New York City Department of Health in one of the laundries of a public institution, where she still remains." "In another instance an epidemic of typhoid in the Tenth German Army Corps in the summer of 1909 was traced to a chronic carrier in the case of a woman who prepared vegetables and who had assisted in the prep- THE HOUSE-FLY 19 aration of vegetable salads. The typhoid bacillus grows on the surface of potatoes readily, and this accounted for the outbreak, on the necessary supposition that the woman was of uncleanly habits. The curious point in this case was that she had had typhoid thirty-six years previously for the only time." It is difficult to detect these chronic carriers, and often a serious problem to know what to do with them when found. It is evident that they are dangerous and un- doubtedly many, of whose presence we are unaware, are in existence. It is important that all possible efforts should be made to detect them and it is equally important that none of them should be allowed to take any part in the production or sale of milk or its products and no part in preparing and handling food. FLIES THAT BREED IN HUMAN EXCREMENT Since flies take up bacilli on their feet, from places where they breed and over which they walk and carry them into our dwellings, it becomes pertinent to ascertain what flies breed in human excrement and whether such flies enter our houses. L. O. Howard, in an investigation of this subject, found that 36 species of flies actually breed in human feces and 41 species were found visiting this substance or feeding upon it. Of these 77 species, he found that six were in the habit of visiting houses and were actually caught in dwellings. At the head of these stood the common house-fly, which was, by far, the most abundant fly in houses, but not, be it said, the most numerous one on the excrement. It is almost superfluous to point out and emphasize 20 HOUSEHOLD INSECTS the great desirability of protection from these filth- carrying and quite possibly disease-carrying insects. METHODS OF PREVENTION The ideal method of fighting house-flies would be to destroy the eggs and maggots, just as we fight mosqui- toes, but the problem is a difficult one, especially in the country, where open closets exist and horse and cow stables are always present. The opportunities for flies to breed are really very great, and waste material in the form of decaying animal and vegetable matter is an in- variable accompaniment of life. There is much that can be done, however, to lessen the dangers from this insect. Treatment of manure piles. — Domestic animals are absolutely necessary, but it is not necessary to throw the manure from horse and cow stables and from pig-pen and poultry house out into piles in the open yard to lie there for weeks and become ideal breeding grounds for flies. The treatment of manure piles with a substance to kill the maggots has been tried by Howard, Forbes, Herms, and others. Howard found that chloride of lime was an effective maggot-killer and that one pound of it mixed with eight quarts of horse manure killed 90 per cent of the maggots in less than twenty-four hours. Unfortu- nately, chloride of lime costs at least three and one-half cents a pound and, in addition, the chlorin fumes from treated manure piles act as an irritant to the eyes of live stock. If the manure is piled away from the stable and one does not mind the expense, chloride of lime may prove satisfactory. Otherwise it is probably impracticable. Howard's experiments with kerosene seem to indicate THE HOUSE-FLY 21 that this material is also impracticable. It does not penetrate a large pile of manure with sufficient ease to reach all of the maggots unless so large quantities are used that the cost becomes prohibitive. Ordinary slaked lime has not proved an efficient destroyer of the maggots. J. J. Davis of the University of Illinois, under the direc- tion of S. A. Forbes, carried out some interesting experi- ments in the treatment of manure piles with iron sulphate. This treatment proved so successful in killing the maggots that it seemed possible to make certain recommendations, namely, that a solution of iron sulfate, two pounds in a gallon of water, or two and one-half pounds of dry sulfate would be sufficient for one horse each day. Iron sulfate is so cheap that it would not cost over two cents a horse a day and, in addition, it completely deodorizes the manure. As a basis for this recommenda- tion, it was estimated that the average driving horse produces about fifteen pounds of manure a day, while a working horse might produce twice that amount. But a large part of the manure of the working horse is dropped out-of-doors, so that, perhaps, no more would accumulate for treatment than for a driving horse. The storage and removal of manure. — It has been shown that flies prefer light, open places in which to breed and that they rarely enter dark rooms to deposit their eggs. It therefore becomes an inexpensive and simple matter to build a dark, well screened room or a tight cement pit in which the manure can be stored for a long time or, if preferred, can be removed once or twice a week. Herms describes and illustrates several forms of re- ceptacles for the storage of manure in use in Berkeley, California. He says, "Where only one horse is stabled 22 HOUSEHOLD INSECTS a simple galvanized iron garbage can has been found very useful and convenient, or even a tight barrel covered over with a tightly fitting lid. The contents of these cans or barrels are removed once or twice per week, either by the city scavengers or by gardeners for fertilizing purposes. Where many horses are stabled, as in a livery stable, a larger receptacle must be provided. In such cases, a closet or bin can be constructed at a small cost, which is satisfactorily offset by the absence of the fly nuisance. Such a closet may be built in one corner of the stable, with a small screened door through which the manure is thrown when cleaning the stalls (providing for ventilation), and an outer door giving access to clean out the closet once or twice per week. Or a closet of about the same construction may be built in the form of a shed or lean-to, connecting with the stable by means of a small screened door, as above. Where it is not convenient to construct a lean-to of this type because of sliding doors or other obstruction, a bin may be substituted as shown in the figure (Fig. 7). The illustration shows the bin ready to receive the manure ; the bolted door shown in front swings up to allow access in the removal of the manure. The use of a concrete floor built directly upon the earth is strongly recommended, and the wood inside should be well provided with a heavy coat of tar." Of course, con- FIG. 7. — Bin for holding manure. THE HOUSE-FLY 23 crete bins and pits are preferable to wooden ones, but they are more expensive. In the country, where it is preferred to remove the manure once or twice a week rather than to store it, it should be drawn to the fields and scattered thinly over the surface. If the manure is left in piles or in large lumps, there is still danger of its serving as a breeding place for flies. But if scattered thinly, it will soon dry out and become unsuitable for the maggots. A manure spreader would be an admirable machine for this purpose, for it cuts the manure up fine and scatters it evenly and thinly. Open box privies. — These are more dangerous in a direct way than barnyard manure piles. The flies that breed in these privies and those that breed in the manure piles and afterward visit the privies are a constant source of danger. The feet of such flies are sure to be loaded with whatever germs there may be in such filth and where they eventually visit the kitchen and dining-rooms the food they touch just as surely becomes contaminated with the germs the flies are carrying. Moreover, on farms these flies are apt to contaminate the milk and thus endanger the lives of people consuming it. City health authorities are becoming alive to the dangers of unsanitary conditions on the farms from which milk supplies come. It, therefore, behooves a farmer to pay special attention to these conditions, not only to safeguard the lives of his own family, but to insure the disposal of his milk products to the best financial advantage. There is no longer any excuse for the old open, box privy, cleaned out once a year. It is a positive menace to every house in the near vicinity as well as to individuals living, perhaps, hundreds of miles away because of its possibilities in contaminating milk 24 HOUSEHOLD INSECTS supplies. Some form of sanitary closet must be substi- tuted and the question is so important that it seems worth while to discuss it at some length. Undoubtedly some form of closet by which the waste matter falls in water to be disposed of later or to be carried away immediately through underground pipes to a safe place of disposal is the most satisfactory. In the country, and in a multitude of small country towns probably some form of dry closet will be most used for years to come. A type of closet that serves much better than the open, box privy should, first of all, be built as nearly fly tight as possible. It should have a vault built underneath it of brick and cement or other water-tight material. The vault should be wide enough so that it extends as far back outside of the closet as it extends underneath and should be high enough to prevent surface water from entering it. Of course the part extending outside of the closet must be cloesd with a tight fitting cover. In addition, an abun- dant supply of wood ashes, sifted coal ashes, or fine soil, or lime, should be kept inside and sprinkled freely over the material in the vault by each one using the closet. A liberal use of kerosene oil by pouring it over the material in the vault once every week will aid greatly in destroying the eggs and maggots of the fly. When the part of the vault beneath the seat becomes full, the material may be drawn backward into the outer half of the closet. This may be repeated several times during the year. The material may remain there, but it is best to soak it well with oil occasionally. When it is removed, it should not be used as fertilizer, but should be burned if possible, and if not, it should be buried far from any buildings. A much better form of closet is described and figured THE HOUSE-FLY 25 in detail by Stiles and Lumsden in Farmers' Bulletin 463 of the United States Department of Agriculture. This bulletin may be had by writing to the Secretary of Agri- culture, Washington, D.C. The author would advise all who are interested in this subject to obtain a copy of this bulletin. Two simple types of sanitary privies are described in detail and fully illustrated. Each one is simple in con- struction, inexpen- sive, and sanitary. Explicit directions are given for build- ing them, together with a detailed bill of lumber and materials needed. Fly traps. — There are excellent wire traps for catching flies, that, when baited with some attractive substance, will catch hundreds of these insects. C. F. Hodge is very enthusiastic over the use of traps placed out-of-doors, for instance, on garbage cans, to catch the flies before they enter the houses at all. With one of these traps affixed to a garbage can he caught 2500 flies in fifty-five minutes (Fig. 8). The cover of the can was held up so that there was a small open space all around through which the flies might enter. After they had once FIG. 8. — Hodge's trap for garbage can. 26 HOUSEHOLD INSECTS entered the can, they naturally migrated upward through the hole over which the trap was placed, being attracted by the light which entered only at this place. Hodge argues that we should catch the first original pair of flies in the spring before they lay any eggs and thus escape the whole fly trouble. And he thinks it could be done in some such way if every one would cooperate. The ordinary fly traps are rather small and where flies are abundant have to be emptied too often. It is sometimes desir- able to have a trap in which flies may be caught in large quantities without being fre- quently emptied. A. M. Bull of the engineering divi- sion of the Uni- FIG. 9. — A large fly trap. versity of Minnesota designed a large trap of this kind that has proved very successful (Fig. 9). The trap is twenty-four inches long, eight inches high, and twelve inches wide. It consists of three parts, a baseboard (a), a roof -like trap (6), and an oval part (c). On the base- board are two shallow pans to contain the bait, usually milk and bread. The trap consists of two roof-like screens with several openings along the ridge for the flies to crawl through. These two traps are fastened THE HOUSE-FLY 27 to the board (6). The oval part (c) covered with wire screen is placed over the roof-like traps to receive and hold the flies. The three parts are held together by the hooks at the end (Fig. 10). In Fig. 11 is shown a cross section of the trap, which will aid in explaining the construction. The space between the baseboard and middle portion is about one-half an inch. The bait should be renewed occasionally and not allowed FIG. 10. — End of trap, FIG. 11. — Cross section showing hooks. of trap. to become dry and unattractive. The flies that gather in the upper, oval part of the trap may be killed by pour- ing boiling water on them. Probably galvanized wire screen will withstand the effects of water and general usage without rusting better than the ordinary painted wire. With this trap, the Minnesota people caught in a dairy barn in one day, 1700 flies ; dining hall, rear of building, two days, 3000 flies; same place, five days, 13,000 flies; on the back porch of a dwelling house not far from a stable 28 HOUSEHOLD INSECTS containing a few horses, two days, 8700 flies ; same place, one day, 12,000 flies; same place one and a half days, 18,800 flies. These instances suffice to show the effective- ness of such a trap in certain situations. Insect powder. — There is a powder known as pyre- thrum, Persian insect powder, or buhach, that is sold a great deal for killing all kinds of insects, especially household pests. When the pyrethrum can be obtained in a fresh condition it is an excellent insecticide. There is no more satisfactory way of ridding a kitchen of house- flies than by the use of this powder. Go into a kitchen at night, close all the doors and windows and then sprinkle fresh insect powder over the stove, on the window ledges, tables, in the air, everywhere. In the morning flies will be found lying around dead or stupefied. They may then be swept up and burned. It is often difficult to get fresh pyrethrum and for this reason its use is not always a success. The buhach is a California product made from the pulverized heads of a- species of Chrysanthemum grown near Stockton, California. This powder costs a little more than the Persian powder, but it is apt to be fresher and stronger. It will pay to buy the buhach whenever possible. Another method of using pyrethrum or buhach is to moisten the powder with water and mold it into small cones. These cones are then placed in an oven until they are thoroughly dry. Then they may be set on end in pans and lighted at the tips. The fumes, which are not unpleasant and are harmless to human beings, will kill the flies. It is said that the vapor produced by placing 20 drops of carbolic acid on a hot shovel will also kill the flies. We THE HOUSE-FLY 29 have never tried this and have heard of reported failures. It would seem as though the amount to be used would depend upon the size of the room. Minis culicide. — This is also useful in killing flies as well as mosquitoes. It should be used exactly as is described in the chapter on methods of protection from mosquitoes. Bichromate of potash. — This is a substance often used to kill flies. It is not a virulent poison and, therefore, little danger is incurred in putting it about the room. It should be dissolved in water at the rate of one part of the potash to two of the latter and then set about in shallow dishes. If the room can be darkened except one window and the solution put on the ledge of this one, in the light, the results will be quicker. This substance has not always given good results. Formaldehyde. — One of the best solutions for attract- ing and killing flies is a dilute mixture of formaldehyde (40 per cent) with water and milk. A tablespoonful in a pint of equal parts of water and milk will attract the flies and kill large numbers of them. The mixture should be poured into shallow dishes, soup plates for instance, and a crust of bread dropped into the middle of the dish for the flies to light upon and to facilitate their feeding. If the shades of all of the windows in a room but one are pulled down and a plate of this mixture set in the light, the flies will be attracted and killed. We have cleared a dining-room of every fly in an afternoon in this way. Formaldehyde will not prove so effective in dining- rooms or kitchens where there is food, water, or milk to which the flies have access. It will be most successful where it is the only liquid they can get to drink. For- 30 HOUSEHOLD INSECTS maldehyde is not a virulent poison and little risk is run in using it. Fly papers. — Tanglefoot fly papers should be in use in a kitchen and in a dining-room too, if the latter has flies in it. This fly paper can be had anywhere now, costs little, and is very efficient. No fly should be allowed to live a minute longer in any kitchen than is absolutely necessary. Better, a great deal, that it should live in the parlor. House-flies are very fond of gathering on a string or strip of paper or cloth hanging from the ceiling. This habit is noticeable in any room where flies are abundant and the strips are available. It may be taken advantage of in a very effective manner, namely, by suspending narrow strips of tanglefoot paper from the ceiling. The flies will alight on these narrow strips when they will not go near the sheets lying on a table or window sill. It is amazing how easily and in what numbers they may be caught by this simple device. Disposal of wastes. — Decaying fruits, vegetables, scraps, and slops from the house ought always to be placed in tightly covered cans or barrels or in closely screened rooms until they can be removed and buried, burned, or otherwise disposed of. Scrupulous care and cleanliness should always be practiced around the house. The excretions of patients suffering from typhoid fever, diarrhea, dysentery, and other intestinal diseases should be thoroughly sterilized by treating with a liberal quantity of carbolic acid before being thrown into closets or sewers, or should be burned. Special effort should always be made to exclude flies from a sick room, particularly in the case of contagious PLATE 1 Eggs of house-fly (X4), above; properly screened porch, below. THE HOUSE-FLY 31 diseases. They not only annoy the patient, but they are liable to convey contagion to other members of the household. The faces of babies should be screened with mosquito netting. Protection of food. — Food and confectionery exposed in public places, lunch counters, and restaurants should be protected from flies by screens, cases, or other con- trivances. One ought to boycott lunch counters that expose their food to the dust, flies, and other insects always found in abundance about railway stations, and restaurants. The exposure of fruits in the ordinary street fruit stands in cities is dangerous to public health. The use of screens. — After all is done that seems pos- sible, still there will be some flies, but these may be largely kept out by a thorough screening of all doors and windows, as is fully described in the discussion of the mosquito. Especially will there be flies and filthy, germ-bearing ones, if the neighbors take no pains with their stables and closets. Flies enter a house largely through the back door of the kitchen. They are attracted to this opening by the odor of the cooking and by the warm air pouring outward when the door stands open. This is especially noticeable on a wire gauze door toward night if the main door is left ajar. The wire screen is often literally black with flies and whenever it is opened some of them are almost sure to enter. Moreover, this door is opened, probably, more than any other in the house. The only efficient method of keeping flies out of the kitchen is to build a porch (Plate 1) over the back door and screen the three open sides. Of course a wire gauze door must be placed in one side wherever it is most desired. With this arrangement, the flies cannot gather on the screen 32 HOUSEHOLD INSECTS door of the kitchen, and they do not gather on the porch screen door any more than anywhere else because there is no warm air or odor there. REFERENCES TO ECONOMIC LITERATURE ON THE HOUSE-FLY 1836. SPENCE, WILLIAM. — Observations on a mode practiced in Italy of excluding the common house fly from apartments. Trans. Ent. Soc., London, Vol. 1, pp. 1-7. 1869. PACKARD, A. S. — Observations on the anatomy and life history of the house fly. Amer. Nat., Vol. 2, pp. 638-640. 1874. On the transformations of the common house fly with notes on allied forms. Proc. Bost. Soc. Nat. Hist., Vol. 16, pp. 136-150. 1896. BUTLER, E. A. — Household insects, p. 172. 1896. HOWARD, L. O. — The principal household insects of the United States. Bull. 4, n. s., Bu. Ent., U. S. Dept. Agri., pp. 43-47. 1896. LUGGER, OTTO. — The housefly. Bull. 48, Minn. Expt. Stat, pp. 173-183. 1898. HOWARD, L. O. — Further notes on the house fly. Bull. 10, n. s., Bu. Ent., U. S. Dept. Agri. pp. 63-65. 1898. - — House flies. Circ. 35, s.s., Bu. Ent., U. S. Dept. Agri., pp. 1-8. 1899. NUTTALL, H. F. — On the role of insects, arachnids, and myriapods as carriers in the spread of bacterial and parasitic diseases of man and animals. Johns Hopkins Hospital Reports, Vol. VIII, pp. 1-152. 1900. REED, WALTER, VAUGHAN, V. C., and SHAKESPEARE, E. O. — Abstract of Report on the origin and spread of typhoid fever in the U. S. military camps during the Spanish war of 1898. Washington Government Printing Office. 1900. HOWARD, L. O. — A contribution to the study of the insect fauna of human excrement. Proc. of the Wash. Acad. of Sci., Vol. II, pp. 541-600. 1901. The carriage of disease by flies. Bull. 30, n. s., Bu. Ent., U. S. Dept. Agri., 1901, pp. 39-45. CHAPTER II FLIES, OTHER THAN THE HOUSE-FLY, THAT FREQUENT HOUSES AMONG the flies commonly found in houses, the house- fly constitutes the major number ; but there are several other species of flies that frequent dwelling rooms, some of which are often mistaken for the house-fly. Perhaps the most common ones found in houses are the biting house-fly, the small house-fly, the cluster-fly, the stable- fly, the "blue-bottle" flies, and the fruit flies. Although the foregoing and a few other species of flies are frequently found in dwelling-houses, the house-fly constitutes, by far, the greater portion of all the flies that may occur in living-rooms. Howard, aided by persons in different parts of the United States, made a collection of the flies found in rooms in which food-stuffs were exposed. Altogether, 23,087 flies were caught from various localities in this country. Of these, 98.8 per cent were the common house-fly. Of the remaining 1.2 per cent, the smaller or lesser house-fly was the commonest species. Hamer, in London, found that more than nine-tenths of the flies in kitchens, and living-rooms of houses near depots for horse-refuse, manure, etc., were the common house-fly. The following table adapted from Johannsen will serve to distinguish some of the more common of these allied species. A hand lens will be needed to make out some of the characters : — 35 36 HOUSEHOLD INSECTS a. Wing with apical veins (M and R) parallel or diverging at tip (Fig. 12). Homalomyia canwvlaris, the lesser house-fly, breeds in waste vegetable substances, and also in excrement. FIG. 12. — Wing of the lesser house- fly. (X 10.) The male has 3 pairs of yellow translucent areas on its abdomen. Several related kinds (Phorbia, etc.) are also frequently seen in houses. Wing with apical veins (M and R) more or less convergent (Fig. 13). FIG. 13. — Wing of house-fly. b. Flies with blue or green metallic coloring. Blue and green bottle flies. Common indoors, especially in spring and fall. They breed in fresh and decaying meat and vege- tables, some in excrement. bb. Flies with dull non-metallic coloring. 'c. With mouth-parts produced and pointed, fitted for pierc- ing (Fig. 16). Stomoxys calcitrans, the biting house-fly, is a trifle larger than the typhoid fly. Especially com- FLIES THAT FREQUENT HOUSES 37 mon in barns. It breeds in vegetable refuse, manure, and excrement. 3 Hcematobia serrata, the horn fly, is similar, but much smaller. It is occasionally found in houses ; common on cattle, cc. With blunt mouth-parts (Fig. 6). d. Last section of vein M of the wing with abrupt angle. e. Thorax with four longitudinal lines and without golden hairs. House-fly, Mwca domestica. ee. A larger fly with no lines on thorax but with golden FIG. 14. — Wing of stable-fly (M. stabulans). (x 8.) hairs. Cluster-fly, Pollenia rudis. dd. Last section of vein M of the wing with a broad gentle curve (Fig. 14). /. Eyes microscopically hairy; each abdominal seg- ment with 2 spots. Larvae are found in dung and excrement. Myiospila meditabunda. ff. Eyes bare; abdomen gray and brown marbled. Muscina assimilis with black legs and feelers, and Muscina stabulans with legs more or less yellowish, and which breeds in decaying vege- table substances, dung, and excrement, are fre- quently found in houses. 38 HOUSEHOLD INSECTS THE CLUSTER-FLY Pollenia rudis The cluster-fly is well-known to most housekeepers because of its habit of entering houses in the autumn and hiding away in protected nooks in large groups or clusters. We have seen a handful of these flies in single clusters in the corners of rooms and beneath garments hung up in closets and beneath curtains at the windows of seldom used rooms. They are a nuisance and a source of considerable annoyance, not from the damage they do, for this is evidently slight, but because of their presence. They are not welcome guests at any time. The cluster-fly is an European insect and it was known there at least a century ago. Just how or when it came to this country is not known. It could easily have come to this country on board ships, for it would as readily enter a ship lying in port on an autumn day as a dwelling house. From its habit of hibernating in clusters all winter it could take several rides back and forth across the ocean before spring. Loew mentions it in a list of flies published in 1864 as common to Europe and America so that it was here some years before that date, at least. Appearance of the fly. — It is slightly larger than the house-fly and appears longer and narrower. This is because the wings, when in repose, overlap each other, thus bringing the outer edge of each almost parallel with the sides of the abdomen. This position of the wings gives the effect of narrowness when viewed from above (Fig. 15). The wings of the house-fly when in repose stand out at a considerable angle to the abdomen. More- FLIES THAT FREQUENT HOUSES 39 over, the thorax of the cluster-fly bears many short, golden hairs. The thorax is of a uniform coloration and lacks the light and dark lines on the thorax of the house- fly. The abdomen is grayish but inclined to be iridescent, and thickly set with hairs, especially at the posterior end and along the sides. Its habits. — Normally the cluster-fly lives out-of-doors, frequenting the flowers and fruits of plants. In the autumn, however, it enters dwelling-houses in search of snug retreats in which to pass the winter. It gathers in clus- ters in the corners of unused, darkened rooms, under clothing in closets, beneath curtains at windows, and in other nooks. A correspondent writes, "Can you give me information con- cerning the house-fly which in late August and September gets ^ ^ _ Tfae duster.fly into unused rooms where there (x 2|.) is no food or odor and bunches in the angles of the wall and behind pictures and fur- niture ? They do not fly much but crawl about in a lazy manner. Screens and every device which works perfectly in excluding the ordinary fly are useless in keeping these out." This letter describes the habits of the cluster-fly admirably. W. H. Dall quotes from a letter of a relative living at Geneva, New York, who had been much troubled with these flies. Evidently the flies had been troublesome in the neighborhood, for the letter says, " people soon learned to look everywhere ; in beds, in pillow-slips, under table 40 HOUSEHOLD INSECTS covers, behind pictures, in wardrobes, nestled in bonnets and hats, under the edges of carpets, etc." They were also said to be found in incredible numbers under buildings between the earth and the floor. Lintner gives several instances of the occurrence of these cluster-flies in buildings in different localities in New York State. The cluster-flies enter a building in the fall one by one through cracks and crevices and afterwards gather in clusters. In the spring they swarm on windows on warm sunny days. When crushed some say they emit an odor like honey, others say the odor is disagreeable. Its life history. — Almost nothing is known of the life history of this fly, as common as it is. Riley states that he found the puparia of the cluster-fly in the roots of grass about three inches below the surface of the ground. Howard says that a single specimen of this fly was reared from cow-manure in the Insectary of the Bureau of Ento- mology at Washington. J. S. Hine of Columbus, Ohio, writes Howard that he reared a number of specimens of cluster-flies from cow droppings in the pasture. Robineau Desvoidy remarks that the eggs of the mem- bers of the genus Pollenia are laid in manure and in de- composing animal and vegetable matter. Methods of control. — We are probably partly safe, at least, in assuming that the cluster-flies lay their eggs on decaying vegetable matter and that the larvae live in these substances. If correct, then the same methods used in the control of the house-fly will also be of benefit in controlling the cluster-fly. However, it is probable that the cluster-fly breeds over much wider areas, — away from buildings, out in the fields and possibly in the woods. FLIES THAT FREQUENT HOUSES 41 In this event, it would be impracticable to control it in the same way as we would the house-fly. The clusters of flies found in the corners of rooms may be swept into boiling water and killed. Fresh pyrethrum or buhach dusted freely on them will kill or stupefy them so that they may be swept up and burned. Screens afford little protection against cluster-flies. A correspondent writes that, "The only way I have found to keep them out of the room is to leave out screens, lower the window from the top, and have the room light." Fortunately, the cluster-flies are often subject to a fungus disease, which kills many of them. This fungus has been determined by Thaxter as Empusa americana. THE BITING HOUSE-FLY Stomoxys calcitrans This fly is commonly known as the stable-fly, but as it frequents houses, bites severely, and is often mistaken for the house-fly, it may well be called the biting house- fly. Because of the mistaken identity between this fly and the common house-fly the popular fallacy that the latter can bite has arisen. The biting house-fly is slightly larger and more robust than the house-fly and has an awl-like proboscis (Fig. 16) with which it can pierce the flesh and cause severe irritation. It will bite through stockings, and is very annoying, sometimes, by biting one's ankles, especially when low shoes are worn. Habits and life history. — This is normally an out- door insect, but it frequently seeks the shelter of houses, especially just before storms and has, therefore, been called the "storm-fly." Other flies, however, have the 42 HOUSEHOLD INSECTS same habits, and the name "storm-fly" is no more appropriate for this fly than for others. It loves the direct sunlight, and may be seen basking on walls and fences in the sun. When darkness begins they seek shelter in protected places, entering stables and other buildings. While camp- ing one summer in the Adirondacks the author pitched his tent in a small wooded pasture near the shores of a lake. Every FIG. 16.— evening these flies (Fig. 17) would come Head and pro- into our tent in numbers and rest on the biting house- walls and roof until the sun appeared the fly. (xs.) following morning. They evidently bred in the droppings of two cows that frequented a moist shady retreat not over a score of yards from our tent. Farm-yards and sta- bles are evidently the usual haunts of this fly, but it is found in fields, about gardens, and in open woods where cat- tle are grazing. Newstead has traced its life history quite fully. He found that the creamy-white eggs were laid in irregular heaps in fresh horse ma- nure and in the feces of other animals. He FJG 17. _ Biting house.flyj stomoxys found the females actu- caidtrans. (x 3|.) \ FLIES THAT FREQUENT HOUSES 43 ally depositing their eggs in numbers in piles of heated lawn grass alongside of a cucumber frame in a garden. Howard has reared the fly from horse and cow manure and remarks, "I judge from the fact that it is attracted to human excreta that it may become a carrier of in- testinal disease." The eggs hatch in two to three days under temperatures ranging from 65 degrees to 72 degrees F. The larvae demand a good deal of moisture and an absence of light for their best development. Under these conditions they attain their growth in two to four weeks. Evidently where soil is available beneath the manure the larvae bore down to it and pupate in the earth. The pupal stage lasts 6 to 26 days. The complete life cycle is, therefore, passed through in from 3 to 4 weeks under favorable con- ditions of light, heat, and moisture. F. C. Bishopp records a very interesting outbreak of the biting house-fly in Texas. The flies, in this case, were found breeding in great numbers in straw stacks. From these situations they swarmed on the live stock, causing serious injury to horses and cattle. Moreover, investi- gation and inquiry disclosed the fact that previous out- breaks of this fly had occurred in former years. Bishopp found the flies breeding in oat, rice, barley, and wheat straw, and in horse manure and cow manure. In the straw stacks, the maggots were found in the wet rotting straw. When the larvae attained their growth they pupated in the straw. A single fly was seen to make three depositions of eggs, laying a total of 278 eggs. The total period from egg to adult varied from nineteen to forty-three days. Howard, in his book on the house-fly, relates an in- 44 HOUSEHOLD INSECTS teresting investigation of the biting house-fly made by Lucien Iches and reported in a paper to which we have not had access. Iches found the flies swarming in great numbers on a large estate in the province of Santa Fe , Argentina. The cattle were very greatly annoyed and driven almost frantic by the bites of the flies. Certain Durham bulls were particularly infested with the flies. The hair had disappeared in spots and the skin was crack- ing. A search for the breeding places showed that the larvae and puparia existed by the millions in the lower portions of piles of straw left from threshing. Fermenta- tion had begun in the straw, thus affording an attractive place for the deposition of eggs. The breeding places were destroyed by burning the straw. The bite of this fly is severe, as any one can attest who has been a victim. Osborne says: "It causes a great amount of annoyance to cattle, horses, and other domestic animals, and it is frequently very troublesome to people working in places where it abounds. Its bite is not poisonous and aside from the pain given and the possibility of its disseminating disease, it is less injurious than some other members of the group. When abundant, however, this annoyance may be very great, and they all deserve attention." Bold gives an interesting note regarding the severity of the bite on cattle. In this case fourteen cows under the treatment of a veterinary surgeon were generally bitten on the legs, shoulders, and rarely on the necks. "In some of the severe cases the joints were so much swollen that the poor animals could not bend their legs to lie down ; and in them the inflammation rose so high as to cause the loss of the outer skin and hair. The flies FLIES THAT FREQUENT HOUSES 45 appeared to prefer the knees and upper portion of the foot in the cow, frequently crawling from thence to the hands of the veterinary, but on him their bite had no injurious effect." Relation to disease. — The biting house-fly has been suspected of transmitting disease, particularly among domestic animals. They have been charged with trans- mitting glanders from diseased to healthy animals and anthrax among cattle. Schuberg and Kuhn have lately shown, experimentally, that this fly is capable of trans- mitting certain trypanosomes in a mechanical manner to healthy animals. In 1912, Brues and Sheppard brought together certain evidence pointing toward this fly as a transmitter of infantile paralysis. Later, in September of that same year, Rosenau and Brues announced that they had experimentally transmitted infantile paralysis, through the agency of Stomoxys calcitrans to monkeys which were suspectible to the disease. In the month following, October, Anderson and Frost, of the Public Health and Marine Hospital Service, announced that they had re- peated the experiments with similarly positive results. We therefore find that four scientists working in groups of two, independently of each other, have demonstrated that the biting house-fly is a transmitter of infantile paralysis among monkeys susceptible to the disease. Moreover, Brues and Sheppard have shown that the seasonal occurrence, distribution, and other facts con- nected with Stomoxys agree wonderfully well with the conditions of an epidemic of this disease. From all the evidence at hand we are justified in looking upon the biting house-fly with considerable suspicion, for it may be a transmitter of infantile paralysis among children. It must 46 HOUSEHOLD INSECTS be said, however, that later experiments by different workers have given only negative results in the trans- mission of this disease. It has been suggested, with some show of reason, that this fly may play a role in the transmission of pellagra. THE STABLE-FLY Muscina stabulans The stable-fly resembles the house-fly considerably but it has a longer and more robust body. It is evidently not as abundant in houses as some of the other species. Hewitt says he usually finds it in the early summer be- fore the house-fly has ap- peared in any numbers. It seems to be widely dis- tributed in this country and in Europe and is often mistaken for the house-fly (Fig. 18). The dorsal side of the thorax is gray and FIG. IS. — The stable-fly, Muscina , T • stabulans. (x 3.) bears tour dark longitudi- nal lines quite similar to the thorax of the house-fly. The eggs of the stable-fly are laid on decaying vegetables, fruits, fungi, and in cow manure. Hewitt says that the larvae sometimes attack growing vegetables, probably having been introduced about the plants in manure. Howard found the flies frequenting human excreta and the larvae breeding in this material. It has been reared FLIES THAT FREQUENT HOUSES 47 from the pupae of the cotton-leaf worm, the gipsy moth, and from pupae of certain Hymenoptera. It has also been reared from masses of the larvae and pupse of the imported elm leaf-beetle. The chances are that it was not parasitic on these insects, but that the pupae were in a decaying condition, thus acting as food for the larvae. The life history of this fly is not known in detail, but Taschenberg says that the life cycle occupies from five to six weeks. The larva of this fly has been known to pass through the alimentary tract of man. In this case access was probably gained to the stomach through vegetables eaten by the individual. The relation of this fly to the dissemination of disease is not definitely known, but it is a species that should be considered with suspicion until proven guiltless, at least. It breeds in human excreta and is evidently attracted to this material, especially when it is deposited in open places. As it enters houses there is thus ample op- portunity for it to pick up and convey disease-producing germs. Its scientific name, stabulans, was given to it before its habits were known ; but in the light of what we now know of its breeding places there seems to be little appropriateness in the name stable-fly. THE LESSER HOUSE-FLY Homalomyia canicularis In early spring, in May and June, before the house-fly appears, there are often numbers of small flies frequenting rooms and crawling on the window panes. Chief among these is the lesser house-fly. It is considerably smaller than the house-fly and by many is considered a young 48 HOUSEHOLD INSECTS house-fly not full-grown. The Germans call it the " Kleine stiibenfliege, " which means little room-fly or house-fly. The lesser house-fly differs markedly from the house-fly not only in size, but in other characters. The fifth vein of the wings runs straight out to the edge without the sharp upward curve of the same vein in the wing of the house-fly. Indeed, the lesser house-fly belongs in the family Anthomyiidce, a family considered, by some authors, distinct from the Muscidoe, which contains the house-fly. Although the lesser house-fly appears rather early in the season, it is soon lost among the greater numbers of the house-flies that come on in June and July. The larvae of the lesser house-fly differ very much from those of the house-fly. The body is compressed or flattened and along each side bears a double row of spiny processes very different from the perfectly smooth maggots of the house-fly. The dirt usually clings to the spines, thus giving the maggots a dirty appearance. The full- grown maggot measures from £ to \ of an inch in length. The larvae of the lesser house-fly live in waste vegetable matter, in the manure of different animals and especially in human excrement. Hewitt says he has found them very abundant in privies. This habit of breeding in excreta of various kinds makes the flies dangerous inhabit- ants of our rooms. They may act as conveyors of disease- germs quite as readily as the real house-fly. They are rapid breeders, for a generation may be produced in two weeks in hot weather. It is interesting to know that some of the Anthomyiids are parasitic on other insects, while some are well-known pests of garden crops, for example, the cabbage-root maggot, the onion maggot, and the beet-leaf miner. FLIES THAT FREQUENT HOUSES 49 THE BLUE-BOTTLE OR BLOW-FLIES Calliphora erythrocephala and Lucilia ccesar There are certain large flies known as "blue-bottles," "green-bottles," or "blow-flies" that are found in houses, especially during June and early summer. They may be recognized by their large size, buzzing noise, and blue metallic colors. The common blow-fly, C. erythrocephala, has a bluish-black thorax and a dark metallic blue abdo- men (Fig. 19). The eggs of this fly are usually laid on fresh or decaying meat, although they may be de- posited in SOreS Or WOUnds FIG. 1!J. — The blow-fly. (X2.) of living animals. The fe- male blow-fly seems capable of laying a large number of eggs. Portchinsky records finding 450 to 600 eggs from a single fly. Hewitt found that a generation of these flies was produced in twenty-two to twenty-three days. Normally, this blow-fly lives out-of-doors, but it often enters houses in search of material upon which to deposit its eggs and evidently also for shelter. It has been found frequenting human feces and for this reason may be suspected of bearing intestinal bacteria, thus making it a fly to be dreaded. The other "blue-bottle" (L. coesar] is smaller than the 50 HOUSEHOLD INSECTS one just discussed and is more brilliant in color, — some- times bluish and sometimes greenish. It is common in this country and in Europe. It frequently enters houses, especially just before rain-storms. It breeds in carrion, in sores on living animals and in the excrement of man and other animals. The larvae are very similar to those of the first blow-fly discussed except that they are smaller. THE MOTH-FLIES Psychoda mirnda There are often found upon window panes certain tiny flies with broad wings densely clothed with hairs. In appearance they resemble very small moths and are, therefore, known as moth-flies. They belong to the family Psychodidse and may be distinguished from all other flies by their moth-like appearance. The larvae of some of these flies live in cow-dung, others in decaying vegetation, while some live in water, especially sewage water or drain water from kitchens. We have seen hundreds of these moth-flies among the weeds overhanging a ditch carrying the drainage water from a kitchen. We have also seen them in abundance along ditches carrying sewage water from houses. In the first-mentioned instance they were always present on the window panes of the kitchen, readily passing through the ordinary wire screen. Judg- ing them from the places in which they breed, we would consider them unwelcome guests in our houses. Almost nothing is known of the life history of the North American species. Kellogg found the larvae of one species of moth-fly, Pericoma calif ornica, in a stream in California. He found the larva were slug-like, about one-tenth of FLIES THAT FREQUENT HOUSES 51 an inch long and that they clung to stones in the stream by a row of eight suckers on the ventral side of the body. When ready to pupate the larvse crawl higher up on stones where the spray dashes on them. The pupa? are small, flatish, and breathe by a pair of respiratory tubes on the thorax. After about three weeks the adults issue and fly to the overhanging weeds. It is an interesting fact that one of the species of this family is a carrier of the disease known as phlebotomus fever. This disease occurs in the countries surrounding the Mediterranean Sea and the fly concerned in carrying the fever is Phlebotomus papatasii. The habits of this fly seem to be similar to those of the related species occurring in this country. The adult fly is said to be a vicious biter, although very small, and does its biting entirely at night. We have one species of Phlebotomus in the United States, but it is not known whether it will act as a carrier of this disease or not. It seems also to have been demonstrated that a species of Phlebotomus in South America transmits the disease verruga. REFERENCES TO ECONOMIC LITERATURE ON THESE FLIES THE CLUSTER-FLY Pollenia rudis 1883. DALL, W. H. — Proc. U. S. Nat. Mus., Vol. V, p. 635. 1893. LINTNER, J. A. — Ninth Kept., N. Y. Ins., pp. 309-314. 1911. HOWARD, L. O. — The house-fly, disease carrier, p. 236. See Lintner's ninth Rept. for further references. 52 HOUSEHOLD INSECTS THE BITING HOUSE-FLY Stomoxys calcitrant 1865. BOLD, T. J. — Entomologists' Monthly Magazine, Vol. 2, pp. 142-143. 1896. OSBORN, HERBERT. — Insects affecting domestic animals. Bull. 5, n. s., Bu. Ent., U. S. Dept. Agri., p. 122. 1906. NEWSTEAD, ROBERT. — Journal of Economic Biology, Vol. 1, pp. 157-166. 1911. HOWARD, L. O. — The house-fly, disease carrier, p. 240. 1912. BRTJES, C. T., and SHEPPARD, P. A. — The possible etiological relation of certain biting insects to the spread of infantile paraly- sis. Jr. EC. Ent., Vol. 5, No. 4, pp. 305-324. 1912. ROSENAU, M. J., and BRUES, C. T. — Some experimental observations upon monkeys concerning the transmission of poliomyelitis through the agency of Stomoxi/s calcitrans. Bull. Mass. State Board Health, pp. 314-317. 1912. ANDERSON, J. F., and FROST, W. H. — Transmission of poliomyelitis by means of the stable fly (Stomoxys calcitrans). Public Health Reports, Vol. 27, No. 43, pp. 1733-1735. 1913. BRUES, C. T. — The relation of the stable fly (Stomoxys calcitrans} to the transmission of infantile paralysis. Jr. EC. Ent., Vol. 6, pp. 101-109. 1913. BISHOPP, F. C. — The stable fly (Stomoxys calcitrant) an important live stock pest. Jr. EC. Ent., Vol. 6, pp. 112-126. 1913. The stable fly. Farmers' Bull. 540, U. S. Dept. Agri. THE STABLE-FLY Muscina stalntlans 1880. TASCHENBERG, E. L. — Praktische Insekten-kunde, Part IV, p. 108. 1909. HEWITT, C. GORDON. — The Quarterly Journal of Micro- scopical Science, Vol. 54, Part 3, p. 360. 1911. HOWARD, L. O. — The house-fly, disease carrier, p. 248. FLIES THAT FREQUENT HOUSES 53 THE MOTH-FLIES Psychodida; 1895. COMSTOCK, J. H. — Manual for the study of insects, p. 428. 1901. KELLOGG, V. L. — An aquatic psychodid. Entomological News, Vol. 12, pp. 46-49. 1905. American insects, p. 319. THE LESSER HOUSE-FLY Homalomyia canicularis 1909. HEWITT, C. GORDON. — The Quarterly Journal of Micro- scopical Science, Vol. 54, Part 3, p. 354. 1911. HOWARD, L. O. — The house-fly, disease carrier, p. 246. THE "BLUE-BOTTLES," OR BLOW-FLIES 1909. HEWITT, C. GORDON. — The Quarterly Journal of Micro- scopical Science, Vol. 54, Part 3, pp. 358-361. 1911. HOWARD, L. O. — The house-fly, disease carrier, p. 252. CHAPTER III MOSQUITOES, THEIR HABITS AND DISEASE RELA- TIONS MOSQUITOES are really a kind of small fly differing from house-flies in size and in their power to "bite." They are no more abundant to-day than they were a century ago; but much greater interest is shown in them nowadays than formerly because of their relations to certain diseases. Since the discoveries were made that mosquitoes carry certain diseases the hum of one of these insects has come to have an entirely new meaning for us. Before, our only thought was to kill the insect to prevent it from annoying us. Now, we see visions of sickbeds, feverish patients, suffering, and, in many cases, death. Naturally, a great deal of interest in mosquitoes has been aroused, and very properly so, because we should take an interest in anything that affects our health. There are known to be nearly 400 different kinds of mosquitoes in North America alone, and over sixty species occur in the United States. Not over half a dozen of these are common about our houses and only three1 of them are known to carry malaria and only one is concerned in disseminating yellow fever. The malarial species occur all over the United States in sufficient numbers 1 The three species are Anopheles quadrimacidatus and Anopheles crucians with Anopheles psetulopunctipennis as a probable third host. MOSQUITOES 55 to carry malaria to thousands of people. It must be said, however, that our most common and abundant species of mosquitoes have no connection with human diseases, so far as we know, and are of importance only because of their extreme annoyance in biting. Mosquitoes are found in both salt and fresh water. It would seem as though these insects bred in greatest numbers in saltwater, and we usually find areas of greatest infestation along the seacoasts. The greater number of our common species of mosquitoes belongs to the genus Culex. So far as known, none of these are disease- carrying. There are three species belonging to the genus Anopheles in the United States that have been shown to carry malaria in some one or more of its forms. Finally, there is one species of mosquito, Aedes calopus, that has been proven to carry yellow fever. In order to control mosquitoes intelligently, one should understand something of their life histories and habits. LIFE HISTORY OF A COMMON MOSQUITO Throughout the interior of the United States probably the house mosquito, Culex pipiens, is the most common. It is a so-called European species, but has now been de- termined as present quite generally over the country. So far as is known, it neither transmits malaria nor yellow fever to human beings. It is, therefore, of importance largely because it greatly annoys man. We portray its life history (Fig. 20) and habits here, because it is famil- iar to every one and thus serves as an example to show how mosquitoes live. It breeds in almost every place in which fresh water may be found, in quiet pools, road- 56 HOUSEHOLD INSECTS side ditches, sewer ditches, hollow stumps, rain-barrels, cisterns, tin cans, watering-troughs, and other receptacles. Some instances of curious places in which the larva? have been found will be given later. FIG. 20. — Life history of a hou The adult mosquitoes, in the fall, hide away in cellars, barns, outhouses, or other suitable places and there pass the winter in a dormant condition. Probably the majority of these hibernating mosquitoes die before spring. Those females that survive the winter become active in the early spring, and after feeding or sometimes without obtaining MOSQUITOES 57 food, seek a convenient pool of water on which to deposit their eggs. Eggs. — The eggs of Culex pipiens are laid on the sur- face of the water in more or less boat-shaped masses, (Fig. 21). Each mass contains from 75 to 200 eggs, con- sequently they vary much in size. They measure from ^ to ^ of an inch in length and are plainly visible to the eye. The eggs stand on end in regular rows with the larger ends down. When first laid the masses appear yellowish white, but a little later they FlG- 21 become dark brown in color and appear as small masses of soot floating on the water. Very often where there are many egg masses on the water, several of them will run together by capillary action and form a raft of eggs on the surface. We have seen as many as a dozen of these egg masses clinging to each other. Each individual egg is long and cylindrical, larger at the lower end, and tapering to the upper end. As seen from the side, it resembles the blade of a knife (Fig. 20, d). These eggs float on the surface of the water from twenty-four hours to several days, depending upon the temperature, and then hatch. Larva. — When the egg hatches, there issues from the lower end a larva, or "wriggler." Every one that has looked into rain-barrels that have stood for some time during hot weather has surely seen "wrigglers." These are the product of mosquito eggs. The larva of Culex pipiens rests for the greater part of the time with the tip of the abdomen at the surface of the water, and the head 58 HOUSEHOLD INSECTS hanging downward at an angle of 40 degrees. At the tip of the eighth abdominal segment is a long tube known as the respiratory tube (Fig. 20, ...I oenneo spaces, covereo wun WIIUJQU scales, sunateu on the front margin of each wing* three-f oorths of Ac lengtk of the wing from the body, is a yeuowkh white spot. These two spots together with the other give the mosquito a very handsome an pearance. wsnxcnvE IHTFEEEXCES BETWEEX IHK ADTLT FEMALE AXOPHELES AXD THE FEMALE MOSQCIHMES OF ' - doee by and at rest. From theheadof thefemaleAnoph- _i ti . -» !•» «, eies tnere project tnree long, siender ^^M** of nearly the head of the female Coles there k only one ptujccliam, Figtire 27 gives an idea of thfe 6WerenceT ahhoogh Ae parts are much enlarged. Another dMfaeiiLe between Ae then* restcmg positions. When the Culex. ansjits on a wall it rests wiA fe body 66 HOUSEHOLD INSECTS parallel to that wall like a house-fly ; but an Anopheles mosquito usually rests with its body at a considerable angle to the surface. We have seen Anopheles clinging to the ceiling in a horse stall by their four front legs with their bodies hanging almost straight downward. Moreover, the wings of all of the common Anopheles are more or less spotted, while those of Culex are plain and clear. BREEDING PLACES OF ANOPHELES It is quite as necessary to know the places in which these mosquitoes breed as to know their life history, if one wishes to destroy them before they become full- grown. The common mosquito (C. pipiens) breeds in barrels, tubs, cisterns, and other receptacles about the house and is, therefore, known as the house mosquito ; but Anoph- eles rarely breed in such situations. They choose a ditch, a pool, or the shallows of a spring brook, creek, or river for their breeding places. It is important to note that all these breeding places are in water standing or running on the ground and only occasionally in barrels, buckets, or other receptacles about dwelling-houses. In this respect the malarial mosquitoes are quite different from the common Culex, which breeds in almost any situation where it can find water. THE YELLOW FEVER MOSQUITO Aedes calopus = Stegomyia fasciahi The yellow fever mosquito is a small day-flying species with white banded legs and silver lines on the back of the MOSQUITOES 67 thorax (Fig. 28). It is commonly known as the "day" mosquito, "tiger" mosquito, "gray" mosquito, and "calico" mosquito. It is undoubtedly not a native mos- quito of the United States, but has been introduced through commercial inter- course from tropical countries. It is, however, widely dis- tributed south of the Mason and Dixon line, and has been reported as far north as New York, where it was probably car- ried by boats. It is primarily a house mosquito in towns and cities and is seldom found around country homes. Its life history is similar to that of Culex. The eggs are black in color and covered with a shining membrane. They are cigar-shaped and are found singly or in groups near or on the surface of the water in rain-barrels, cisterns, tanks, or other receptacles for water about the house. The eggs are very resistant to cold and to drying, but under favorable circumstances hatch in ten hours to three days. The larvae are very active, always searching and foraging FIG. 28. — The yellow fever mosquito. (XT.) 68 HOUSEHOLD INSECTS for food. They attain their growth in from seven to eight or ten days. The pupal stage lasts about two days, so that the whole life cycle maybe passed in two weeks or even less. The yellow fever mosquito seems to be most active and to do most of its biting in the afternoon and early evening, although Miss Mitchell says that in Baton Rouge it troubled her most before 9 P.M. We have found them particularly active in the early afternoon on shady porches. Yellow fever cannot become epidemic where this mosquito is not present. Any one can remain among cases of yellow fever with perfect safety if he avoids being bitten by an infested mosquito. BREEDING PLACES OP THE MORE COMMON MOSQUITOES In general, it may be said that almost any body of fresh water in almost any situation, if left standing long enough, will become infested with larvae of mosquitoes. In the ditches that receive sewage, we have seen a black fringe of larvae on both sides for nearly a mile. It is ordinarily supposed that mosquitoes breed only in stagnant water, or in water that is changing very little. We have found them breeding in considerable numbers in troughs for watering stock, when the water ran in at one end and out at the other all the time. We have found an unused room swarming with mosquitoes that came from a bucket of slop water. A friend of mine tells me of finding an abundance of wrigglers in a glass globe of water standing on a table in the parlor of a house at which he was visiting. Fish had been kept in the globe, among some water plants growing there. The fish had died some time before and MOSQUITOES 69 had been thrown out and now the family were wondering where the mosquitoes were coming from. HOW FAR DO MOSQUITOES FLY? The answer to this question is an important one since upon it depends the success of certain methods of exter- mination. Owing to the careful observations of John B. Smith, and his corps of workers, we are able to answer the question with some degree of certainty. In the first place, it is held that Anopheles mosquitoes do not fly far — probably not more than half to three-quarters of a mile and usually not nearly so far. On the other hand, cer- tain saltwater mosquitoes fly many miles, especially when aided by a strong wind. Fortunately, these do not carry disease so far as we know. The domestic mosquitoes, Culex, under ordinary con- ditions, do not fly far from their breeding places. The yellow fever mosquito is essentially a domestic one and breeds near dwelling-houses. Miss Mitchell says that "the mass of evidence by experts is to the effect that the greater number of species are not in the habit of flying more than two hundred yards to a quarter of a mile, and that most places, not situated near a salt marsh, will be found to be locally infested. ... If mosquitoes, not the marsh species, are plentiful in a city, the chances are that the breeding place is near by." THE BITE OF A MOSQUITO The beak of a mosquito is made up of six bristle-like or lance-like organs inclosed in a sheath. This sheath 70 HOUSEHOLD INSECTS constitutes the part of the beak that we see from the outside. The bristle-like organs inside are the real puncturing part of the beak, for the sheath does not enter the flesh when a mosquito bites. The sheath bends and the bristles project beyond the end and bore their way into the flesh. The whole apparatus serves as a carrier to conduct the blood to the mouth. While the mosquito is puncturing the skin an irritating substance, the chemical nature of which is not known, is injected into the wound. It is thought by some authors that this poison comes from special glands situated be- tween the salivary glands in the mouth of the insect. Others think it comes from the salivary glands themselves, while others think it is a liquid secreted in certain pouch- like organs connected with the esophagus and known as the cesophageal diverticula. At any rate a sensation of itching is produced by the bite. The immediate area turns red, becomes inflamed, and in some individuals much swelling follows. The itching and irritation may be relieved by the appli- cation of dilute solutions of ammonia or a 5 per cent solution of carbolic acid or a 1 per cent alcoholic lotion of menthol. RELATION OF MOSQUITOES TO MALARIA It has been common knowledge, for nobody knows how long, that in some way malaria is connected with stagnant or standing water. Along with this we have also known that malaria is most prevalent in bottom lands, valleys, swamps, and in regions at the mouths of rivers because it is in such places that water collects and stands. It has MOSQUITOES 71 been learned from experience that by moving to high, dry situations malarial fevers may be avoided. The disease has been attributed not so much to the water as to the so-called miasmatic airs that arise from the water and wet soil. In fact, malaria means bad air. Not long ago the writer heard a person object to building a house in a certain valley-like depression because the cold, damp air might cause malaria. It is a common precaution against malaria to go within doors at early dusk and remain until daylight, for the purpose, it is thought, of escaping the damp, fever-giving atmosphere. It is true that there is a definite relation between malaria and low lands, swamps, stagnant water, marshes, and exposure out-of-doors at night in which people have believed so long. The relation, however, results from a very different agent than has been generally supposed heretofore. Within the last few years, it has been con- clusively and repeatedly demonstrated that malaria is conveyed to human beings and communicated to the blood by mosquitoes and not by miasmatic airs arising from swamps and marshes. The question immediately arises, how does this accord with the relation of malaria to low lands, marshes, swamps, stagnant water, exposure at night, and the like ? The facts as we now know them give the answer. We now know, by scores of investiga- tions, that mosquitoes can exist only where there is water ; that they are abundant in swamps, marshes, and low lands, and that they (malarial mosquitoes) fly and inflict their bites mainly at night and that they are not usually present in high, dry situations. Our next great proof of the relation of mosquitoes to malaria is the fact that the germ causing malaria has been 72 HOUSEHOLD INSECTS carefully and repeatedly traced through its life history, and it has certainly been found to pass a part of its exist- ence in man and a part in the body of the mosquito. Moreover, the part of its life that is passed in man is not like that passed in the mosquito, but both are necessary to the ultimate existence of the germ. These facts have been independently worked out by some of the world's greatest scientists : Ross, Celli, Bignami, Daniels, Laveran, Shipley, Bastianelli, and others. To those familiar with the lives and habits of the lower animals it is not at all difficult to believe that one of them can pass part of its life in the body of one animal and the rest of its life in the body of a second animal. Many cases of this kind are known and some of them commonly known. For example, a common tape worm which exists in the bowels of a human being spends a part of its life in the body of a hog. In fact, we get this particular tape worm only by eating what is known as measly pork. That is, pork containing young minute forms of the tape worm. The pork is eaten and the tiny, undeveloped tape worm set free, which soon grows into an adult worm within our own bodies. Again, there is the liver fluke worm that causes the liver rot of sheep. This parasite passes part of its life in a snail from which, after a time, it crawls up on the blades of grass growing about ponds and pools of water in which the snails live. In this situation the minute worm is swallowed by the sheep along with the grass and finally finds its way to the liver of the sheep. Then, there is that much dreaded parasite, Trichinella spiralis (Fig. 29). This is the little worm on which Uncle Sam spends so much money hiring men to look for it in the carcasses of animals in the great slaughtering and pack- MOSQUITOES 73 ing houses of the United States. If this worm is found in these carcasses, they are condemned and burned because it is by eating them that human beings get the Trichina in their bodies, which may cause death. Many more examples might be given of parasites that live in more than one host. So, after all, the fact that the malarial germ lives in both man and mosquitoes is not a new and anomalous discovery, having no parallel in animal life, for many similar examples have been long and well known. The nearest parallel we have is the germ causing what is known as Texas fever or tick fever, in the cattle of the Southern States. The parasite causing this disease is very similar to the human malarial parasite and acts on the blood of cattle in a similar way, namely, by destroying the red blood corpuscles. It causes fever and chills in the cattle quite similar to those caused in man by the malarial parasite. In fact, many writers call Texas fever Cattle Malaria. This germ spends one part of its existence in the common cattle tick and the other part in the blood of cattle. The germ is conveyed from one animal to another and injected into the blood by the bite of the tick very similar to the manner in which the malarial germ is carried to a person and injected into the blood by a mosquito. It has been demonstrated again and again that if cattle be kept free from ticks, they will not have Texas fever. On the other hand, it has been FIG. 29. — Trichinella spiralis embedded in human muscle, much enlarged. 74 HOUSEHOLD INSECTS repeatedly demonstrated that this fever can be given to cattle by putting ticks on them. Exactly similar facts have been demonstrated in regard to human malaria and mosquitoes. And these experiments constitute our last and final proof of the relation between malaria and mosquitoes. The region known as the Campagna near the city of Rome, Italy, is a low, marshy, wet area, which is one of the most malarious regions in Italy, if not in the world. It is not at all a thickly settled region, because people will not and cannot live there on account of chills and fevers, especially in the autumn during the wet season. Here, if anywhere, was a good place in which to test the whole question of the relation of mosquitoes to malaria in a practical and convincing manner. Here was the water, the marsh, the bad air, the mosquitoes, and the malaria. If people could live in the midst of the Cam- pagna, breathe the bad air, get wet, and undergo all the conditions of life there with one exception, namely, keep free from mosquitoes and their bites, and yet escape malaria, it would certainly convince the most skeptical. Exactly this has been done. Two English physicians, Sambon and Low, in the sum- mer of 1900 determined to satisfy themselves and the world in a practical way of the part that the mosquito plays in malaria. During the summer, they caused to be built in the worst part of the Campagna a small, one- story, five-room house, the windows and doors of which were tightly screened with wire netting so that no mosqui- toes could possibly enter. Here both physicians lived and worked, for they had their instruments with them, during the late summer and autumn while the rainv and most MOSQUITOES 75 malarial season was on. The house stood near the banks of a canal in which was an abundance of the larvae of Anopheles. They went out during the day ; at times allowed themselves to become wet to the skin ; left the windows open at night so that the bad air could enter and circulate all through the house ; in fact, they did every- thing that an ordinary inhabitant would do, with one exception ; namely, they went into the house before six o'clock every day and so evaded being bitten by Anopheles mosquitoes. It must also be mentioned that they took no quinine or other preventive medicines against malaria. It was said that the critical test would come when the rainy season began in the autumn. At this time, the people living under ordinary conditions suffered much from chills and fever. But through it all, these two phy- sicians developed not the remotest trace of chills or fever. It was certainly a remarkable and triumphant vindication of the labors and conclusions of Laveran, Ross, Celli, and many others. But this is not all. There yet lacked one more link in this chain of evidence. The chain had been surely forged link by link during all these years since 1880 through the persistent and brilliant researches of the men mentioned above and now came the forging of the last link that vindicated their wisdom. A son of the renowned Manson, at that time living in London and who had not been in a malarious country since childhood and was therefore as free from the disease as one could well be, offered himself as a subject for the forging of this last link. Bastianelli, the famous Italian whom we have mentioned before, procured some Anopheles mosquitoes and turned them loose upon a man in Rome suffering from malaria. They, of course, bit the man many 76 HOUSEHOLD INSECTS times, sucking his blood and thereby getting the malarial germ into their stomachs. These identical mosquitoes were then sent to London, England, and there allowed to bite Manson. In the regular course of time, he was taken with a well-marked case of malaria and, moreover, when his blood was examined the well-known germs were found in the red corpuscles. Finally, the thing was done. It had been actually proved that men could keep free from malaria by keeping free from mosquitoes and their bites, and lastly it had been proved that the bites of Anopheles mosquitoes would actually produce malaria in a man not previously suffering from it. THE REAL NATURE OF MALARIA Within the last generation tremendous strides have been made in the realms of both pure and applied science ; and if more progress can be said to have been made in one domain of science than in another, it will have to be said of that of medicine. Moreover, with all the remark- able advances made in medicine perhaps no late discovery in that field has aroused more general interest than the discovery in 1880 of the causal germ of malaria by the French physician Laveran, together with the later demon- stration by Ross that this germ is communicated to human beings through the agency of certain kinds of mosquitoes. When Laveran announced that he had discovered a minute organism living in the red cells of the blood and destroying them, thereby causing the disease, malaria, he was not believed. Later, however, his statements were corroborated by other reputable investigators, who had without doubt seen this same tiny parasite in the MOSQUITOES 77 blood corpuscles. Since that time the work has been duplicated and verified by many reliable scientific workers here and in Europe. So that now we know malaria is caused by a very minute animal parasite living in the red cells of the blood and destroying them by the millions. The life history of the parasite has been carefully traced in the blood of man and in the body of the mosquito. History of the parasite in man. — We will suppose that one of these tiny parasites (sporozoif) has found its way into a person's blood from the bite of a malarial mosquito. If conditions are favorable, it soon goes inside of a red blood cell, where it lives and grows, gradually destroying the contents of the red corpuscle, and finally taking up much of the space inside the cell. Finally, the parasite (now called a schizont) inside the blood cell has grown all it will, and it then divides into several distinct individuals (merozoits) commonly called spores. The wall of the red blood corpuscle then bursts and these parasites are set free in the liquid part of the blood. Now if a person has a severe case of malaria, there may be several millions of these parasites in the blood, each one in its own red blood cell. Moreover, all the parasites become mature, form spores, and burst out of these red cells at just about the same time. It is just at the time that the multitudes of minute parasites burst forth into the liquid part of the blood that the chills and rigors be- gin. There are at least three kinds of malarial parasites : (1) the parasite that forms spores and causes chills every two days, thus producing tertian fever; (2) the parasite that forms spores and causes chills every three days, thus producing quartan fever; (3) the parasite that causes malignant fever which frequently becomes very serious. 78 HOUSEHOLD INSECTS The parasites set free in the blood may enter other red blood cells, grow, reach maturity, and burst fortli again. These, in turn, may go through the same course again and again, producing chills and fevers incessantly unless destroyed by some agency. Finally, there appears in the serum of the blood the male and female individuals of the parasite, but these cannot develop farther until taken into the body of a mosquito. History of the parasite in the body of a mosquito. — Suppose while the blood of a malarious person is full of the minute parasites he should be bitten by a mosquito. As the mosquito sucks up the blood some of the parasites would be sure to be taken up with it. After being sucked up into the beak of the mosquito they are carried to the stomach of the insect and there pass through a sexual process. They then enter into the cells of the stomach walls, undergo certain changes, and finally pass through the stomach walls of the mosquito, undergo complicated changes in the body cavity of the insect, and eventually find their way to the salivary glands, from which they are injected through the beak into the blood of the person who is being bitten by the mosquito. There they again enter the red blood cells, pursuing the course already described and causing chills and fevers. Summary. — To sum up, then, malaria is caused by a minute animal parasite that lives within the red blood corpuscles of human beings. This parasite destroys millions of the red blood cells that are so necessary to life and, in addition, secretes certain poisonous substances known as toxins, which lodge in various parts of the body. Its life history has been traced step by step by many careful observers. MOSQUITOES 79 It has been found that the parasite goes through certain stages in the blood of man, but that finally it is taken up by mosquitoes and in the bodies of these insects it goes through certain stages quite different from those gone through in man. Finally, we know that the parasite is injected into the blood of a person by a certain kind of mosquito. Since this parasite lives only in man and the mosquito, it can get from one person to another only through the agency of these insects. In other words, a person once free from the malarial parasite will remain free just so long as the bites of certain species of mosquitoes can be avoided. Number of germs in the blood. — The number of malarial germs in the blood may vary at different times. The more germs there are, the harder will be the chills and fever as a rule. It is easy to see that the more in- fected mosquitoes there are to bite a person, the more germs there will be in the blood and the more severe will be the case of malaria. This is important to bear in mind because it is closely connected with what we shall have to say in regard to methods of prevention. Ross says he "computes that something like a quarter of a billion of them must be present to produce fever." There is another fact that we should also bear in mind, namely, that the germs may actually be present in the body and yet not produce chills and fevers. They may lie dormant in the body, as it were, for a long time and then suddenly become active, increase and produce fever. Under such a condition of affairs circumstances might seem to prove that a person could have malaria without being bitten by mosquitoes. It must be remembered, 80 HOUSEHOLD INSECTS however, that that person was bitten at some time by an Anopheles mosquito, else the germs could never have gained access to the blood. RELATION OF MOSQUITOES TO YELLOW FEVER That yellow fever is not a contagious disease, but one that, like malaria, is carried from one individual to another only through the agency of a mosquito, has been finally and authoritatively settled. It must be said, however, that no one has yet discovered the parasite that causes yellow fever. It is either too small to be seen with any lens now made or it inhabits some organs of the body not suspected or its habits are entirely different from any other parasite with which we are familiar. In any case the germ has eluded all efforts to locate it and scientists are ignorant regarding its real nature, habits, and appearance. PROOFS THAT YELLOW FEVER IS CARRIED BY MOSQUITOES Carlos Finlay, as early as 1881, promulgated the theory that mosquitoes transmit yellow fever and he carried on some experiments at that time in which he claimed to have conveyed the disease from yellow fever patients to non-immunes through the bites of mosquitoes. It was not, however, until the early part of 1900 that more serious experiments were undertaken to determine the actual agents in the transmission of yellow fever, and the relation of this disease to mosquitoes if any existed. During this year a medical commission from the United States Army, consisting of Walter C. Reed, James MOSQUITOES 81 Carroll, Jesse W. Lazear, and A. Agramonte, was sent to Cuba to investigate the whole question. In a field near Quemados, Cuba, this commission of surgeons erected a small wooden building tightly ceiled and with the windows and doors closely screened so that no mosquitoes could enter. In this house, during a total of sixty-three days, seven non-immune men were kept. These men slept in beds furnished with the unwashed pillow-slips, sheets, and blankets that had previously been used on the beds of genuine yellow fever patients in Havana and elsewhere. This bedding was actually stained with the excretions of the fever patients. Neither during that time nor subsequently did one of these seven men develop a case of yellow fever. This indicated to the surgeons, beyond much question, that yellow fever is not carried in clothing, as had always been held. This experiment concluded the first phase of the work. Another house was built in this same field and divided by wire screen from floor to ceiling, into two rooms. The doors and windows of each room were closely screened with fine wire netting so that no mosquitoes could enter. All bedding and material carried into the rooms were disinfected by steam, which precluded any possi- bility of the yellow fever germ being present in the bedding or clothing. In one of the rooms, mosquitoes of a certain kind that had previously bitten patients sick with yellow fever were placed. In the other room none were allowed. Non- immune men were placed in both rooms. Of those in the room containing no mosquitoes, not one had yellow fever. Of those in the other room that were bitten by the infected mosquitoes, six out of seven developed cases 82 HOUSEHOLD INSECTS of genuine yellow fever. This indicated beyond much question that mosquitoes were transmitters of this disease. These experiments have been extended and duplicated many times with the same results, so that we are jus- tified in believing that a certain mosquito known as Aedes calopus is the sole and only agent in the trans- mission of yellow fever. REFERENCES TO ECONOMIC LITERATURE ON MOSQUITOES 1900. HOWARD, L. O. — The mosquitoes of the United States. Bull. 25, n. s., Bu. Ent., U. S. Dept. Agri., pp. 1-70. 1901. Mosquitoes; how they live; how they carry disease; etc. Book, 241 pp. 1901. HERRICK, G. W. — Some mosquitoes of Mississippi and how to deal with them. Bull. 74, Miss. Expt. Stat., pp. 1-31. 1902. Ross, RONALD. — Mosquito brigades and how to organize them. Book, 100 pp. 1902. Malarial fever, its cause, prevention and treatment. Book, 68 pp. 1903. SMITH, J. B. — Mosquitocides. Bull. 40, n. s., Bu. Ent., U. S. Dept. Agri., pp. 96-108. 1903. HERRICK, G. W. — Relation of malaria to agriculture and other industries of the South. Pop. Sc. Mon., Vol. 62, April, pp. 521-525. 1904. SMITH, J. B. — Report of the New Jersey State Agri. Expt. Stat. on the mosquitoes, etc. 482 pp. 1904. FELT, E. P. — Mosquitoes or Culicidse of New York State. N. Y. State Mus., Bull. 79. 1905. HERRICK, G. W. — Notes on some Mississippi mosquitoes. Ent. News, Vol. XVI, p. 281. 1905. BLANCHARD, R. — Les moustiques, histoire naturelle et m&licale. Book, 673 pp. 1906. FELT, E. P. — Mosquito control. 21st Rept. N. Y. State Ent., pp. 109-116. 1906. QUAYLE, H. J. — Mosquito control. Bull. 178, Calif. Expt. Stat., pp. 1-55. MOSQUITOES 83 1907. KELLY, H. A. —Walter Reed and yellow fever. Book, 310 pp. 1907. MITCHELL, Evelyn G. — Mosquito life. Book, 281 pp. 1908. SEAL, W. P. — Fishes in their relation to the mosquito problem. Bull, of the Bu. of Fisheries, Vol. 28, Part 2, pp. 833-838. 1909. BOYCE, R. W. — Mosquito or man ? Book, 267 pp. 1909. HOWARD, L. O. — Economic loss to the people of the United States through insects that cause disease. Bull. 78, Bu. Ent., U. S. Dept. Agri., pp. 1^0. 1910. DOANE, R. W. — Insects and disease. Book, 227 pp. 1910. Ross, RONALD. — The prevention of malaria. Book, 669 pp. 1910. HOWARD, L. O. — Prevention and remedial work against mosquitoes. Bull. 88, Bu. Ent., U. S. Dept. Agri., pp. 1-126. 1912. HOWARD, L. O., DYAR, H. G., and KNAB, FREDERICK. — The mosquitoes of North and Central America and the West Indies. Vols. I and II, Carnegie Institution, Washington, D.C. CHAPTER IV METHODS OF DESTROYING AND REPELLING MOS- QUITOES THE best way to escape annoyance from these insects and to prevent the carriage of disease by them is to destroy them. No one has yet devised practical methods of destroying the adult mosquitoes, hence all of our efforts are best directed against the immature stages of these pests; namely, egg, larval, and pupal stages. The methods taken to destroy mosquitoes fall into three distinct classes ; namely, the drainage of bodies of water liable to contain eggs and wrigglers, the application of oil to bodies of water that cannot be drained, and the intro- duction of fish into pools that cannot be drained or oiled. At the very start one should find out, if possible, what kind of mosquito is causing trouble and then find some- thing about its habits and breeding places. If it is a far- flying species coming from far distant saltwater pools, make up your mind to endure it until it disappears. If it is a local, fresh-water species, then hunt out its breeding places, and use some of the methods outlined in the following paragraphs. DRAINAGE This remedy hardly needs discussion. It is obvious that if a pool be drained or a bucket or barrel be emptied, 84 DESTROYING AND REPELLING MOSQUITOES 85 no mosquitoes can breed there. Tanks not especially needed should be taken down. This should always be done whenever possible, because a tank down and out of the way will be sure to give no trouble. All receptacles like buckets, and barrels, should be looked after and emptied at least once a week, and permanently if possible. Permanent ditches that trouble us most should be tiled and the water conducted a long distance from the house. In many cases, it is much easier to draw a wagon load of earth or even more to fill up a small shallow pool than to dig an outlet. Draining is the most desirable means of fighting mosquitoes because if once well done, it is always done and needs no attention afterward. There are hun- dreds of swamps and marshes near habitations that could be drained with comparatively little expense. When we come to realize fully the discomfort, sickness, and deaths that occur from malaria because of the presence, in the vicinity, of a small swamp in which malarial mosquitoes develop, the small matter of the expenditure of a little money will hardly be taken into consideration. The only question seriously considered will be the one concerning the best method of drainage. FISH VERSUS MOSQUITOES There are often pools or bodies of water that cannot, for one reason or another, be drained. There are also pools and ponds of water used for ornamental purposes that add greatly to the beauty and enjoyment of a land- scape but that serve as prolific breeding grounds for mosquitoes. It is not desirable to drain such pools nor is it feasible to treat them with oils or other substances 86 HOUSEHOLD INSECTS on account of the deleterious effect that may result to the plants growing in the water. Much of the drinking water for stock in many of the states in this country is caught and stored in surface pools. The stock is allowed access to these pools at any and all times. These drinking pools often become breeding places for mosquitoes. The water cannot be drained away because it is absolutely essential for the stock. Neither is it desirable to pour oil on the surface because the water is thereby rendered unpalatable and obnoxious to the animals. In such cases, the best way of controlling the mosquitoes is the introduction of certain kinds of fishes into the pools. In order for a species of fish to be effective in the control of mosquitoes it must possess certain characteristics. In general, it should be a small fish so that it can reach the shallower parts of the pool. It should also be a top- feeder, a voracious feeder on mosquito larvae, and a pro- lific breeder. Finally, it should have a wide geographical range in order to make it available for as many localities as possible. It is evident that but few species of fishes possess the foregoing combination of qualities. It would appear from a knowledge of the habits of the larvae of Anopheles that they are much less easily held in check or destroyed than the larvae of Culex. The larvae of Anopheles are found especially in quiet waters, and in ornamental pools among the lily pads, duckweed, and other plants. They simulate remarkably well their surroundings and are thus screened from observation. Moreover, they live upon the surface, lying and mov- ing in a horizontal plane. It is evident that only those fishes that are small and can penetrate to the spaces of water among the lily leaves and duckweed will DESTROYING AND REPELLING MOSQUITOES 87 ever be able to give relief from Anopheles mosquitoes. Moreover, the fishes must be top-feeders in order to find the larvae lying on top of the water. The goldfish is a good species for introduction into pools, especially ornamental plant pools. This fish is used in Japan for this purpose. In fact, goldfishes, when grown commercially in that country, are fed largely on the larvae of mosquitoes. W. L. Underwood describes the work of goldfish in devouring mosquito larvae as follows : " I took from the pond a small goldfish about three inches long and placed it in an aquarium where it could, if it would, feed upon mosquito larvae and still be under care- ful observation. The result was as I had anticipated. On the first day, owing perhaps to FIG. 30. — Roach or golden shiner. the change of en- vironment, and to being rather easily disturbed in its new quarters, this goldfish ate eleven larvae only in three hours ; but the next day twenty were devou.ed in one hour; and as the fish became more at home the 'wrigglers' disappeared in short order whenever they were dropped into the water. On one occasion twenty were eaten in one minute, and forty-eight within five minutes." Un- fortunately goldfish grow rather large and tend to become cannibalistic. The roach, or golden shiner (Fig. 30), is also an admirable fish for pools and ponds. It is widely distributed and is very abundant. Moreover, it is a very active fish, 88 HOUSEHOLD INSECTS always scouting the waters in search of food. It is always found in large numbers in muddy pools, grassy ponds, and weedy bayous. A species of fish that perhaps meets the requirements most nearly with the possible exception of a wide distri- bution is the top-minnow, Gambusia affinis (Fig. 31). This minnow does not become more than one and one-half to two inches in length. It is active and voracious and feeds near the top, penetrating to the shallowest parts FIG. 31. — Top-minnow. (X 1}.) of the pool about the edges. Here it is safe from its larger enemies and, at the same time, is in the presence of desirable food. It constitutes a most admirable fish for the destruction of mosquitoes in the Southern states. It occurs from the Potomac River and southern Illinois southward and west to Texas. Whether this minnow can be acclimated in northern waters is not yet known. There are also two small species of sunfish, of the genus Enneacanthus, that seem well suited for this purpose. They are widely distributed, are active in pursuit of prey, and live among water plants. In an admirable paper on " Fishes and their relation to the mosquito problem," W. P. Seal sums up the whole question as follows: "The writer has come to the con- DESTROYING AND REPELLING MOSQUITOES 89 elusion, after many experiments in small ponds, that a combination of the goldfish, which is ornamental and useful in the open water, the roach or shiner, which is a very active species, two small species of sunfish, which live among plants, and the top-minnow would probably prove to be more effective in preventing mosquitoes breeding than any other fishes." OIL AS A REMEDY FOR MOSQUITOES The power that oil has to kill the larvae and pupae of mosquitoes has been known for some time. Its practical use against these insects has been of comparatively recent date. How it kills. — If oil be poured upon water, it will sooner or later spread evenly over the surface in a thin film. This film has a comparatively strong tension, and speak- ing from the standpoint of an insect, is very difficult to break. The larva and pupae of the mosquitoes, as we have already shown, breathe air direct by thrusting the ends of the respiratory tubes out of the water. As they come up beneath the oil film, to obtain air, they are unable to push their tubes through the oil, and thus are completely shut off from the air and in a short time drown from suffoca- tion. It may also be said that the oil, as it comes in con- tact with the respiratory tubes, produces injury which hastens death. If any eggs are lying on the surface of the water and are touched by the oil, they are destroyed. Likewise the adult female mosquitoes are caught in the oil and killed when depositing eggs. Kinds of oil to use. — In all my experiments ordinary kerosene oil, such as is used for illuminating purposes, 90 HOUSEHOLD INSECTS was used. In the first place, ditches with their strong currents need a light oil that will spread as rapidly as possible. In the second place, petroleum has cost us just as much as the refined oil, even if bought by the barrel. For bodies of water that have no currents a heavy oil might be superior to ordinary kerosene because the former would not evaporate so quickly and thus need not be applied so often. On the other hand, an oil too heavy will not spread easily, but will gather in spots here and there over the surface, thus losing its effectiveness. Howard says, "so long as the oil flows readily and is cheap enough, the end is gained, provided it is not too light and does not evaporate too rapidly." Other investigators have found, that what is known as "light fuel oil" is the most satis- factory. Amount of oil to use. — Careful experiments have shown that, in general, one ounce of kerosene is sufficient for every fifteen square feet of surface. One-half of a tea- cupful for a barrel is amply sufficient. If the oil is applied with a spray pump and fine nozzle, smaller quantities will be used. How to apply oil. — For small pools, ditches, and tanks, a five-gallon knapsack spraying machine (Fig. 32) is almost ideal. The sprayer should have ten or twelve feet of hose attached and the hose should be furnished with a good nozzle tied to a pole about six feet long. With the pole the operator can reach both sides of a ditch and all sides of a tank without changing position. In cases of barrels, cisterns, and cans, the oil may be poured on or thrown on from a cup, dipper, or other re- ceptacle. In fact, it may be applied to the surface in many cases from a bucket sprinkler. DESTROYING AND REPELLING MOSQUITOES 91 How often to apply the oil. — It has been shown in our study of the life history of Culex pipiens that the entire life cycle may be passed in ten or twelve days. In the case of Anopheles, the life cycle lasts from eighteen to twenty days. These facts alone indicate the necessity Fio. 32. — Spraying a ditch for mosquitoes with a knapsack sprayer. of frequent spraying. I have found that once in two weeks is often enough for sewage ditches. No doubt the oil is effective along the shallow edges of these ditches for some time after it is applied. That is to say, the oil along the edges does not run off immediately because of no current. On quiet pools oil is effective for several days after it is applied because it does not readily evaporate. 92 HOUSEHOLD INSECTS It is safe to say that an application of oil should be made at least twice a month to be surely effective. Pos- sibly in certain cases oftener, especially in drains where the current is fairly strong. Is the pouring of oil into water-closets effective in sewer ditches ? — It has been asked of the writer so many times whether or not the same thing could be accomplished by pouring oil into the closets and allowing it to run down the sewer pipes, as by spraying, that it seemed worth while to give this point considerable attention. Ac- cordingly, I poured two quarts of illuminating oil on the surface of the water in a main sewage ditch near the mouth of the tile to watch its effect below. A fairly quiet pool about two rods long and about fifteen rods below the outlet was selected as the first place of observation. Both sides of the pool were lined with multitudes of larvae and pupae lying in the shallows and in the miniature bays hollowed out of the sides of the bank. By the time the oil reached the pool it was well distributed. The result was, however, that the current was too strong to allow it time to spread into the quieter parts and bays of the pool. It was carried for the most part straight by. Many of the larvae and pupse, however, lying next to the current were so greatly disturbed that they blundered into the middle of the stream and were drowned beneath the film of oil. In a second and similar pool, about ten rods farther down, the effect was noted again. The oil had spread out even more by this time, but the effect was about the same. The majority of larvae and pupae escaped because the current gave the oil insufficient time to spread over them. Nevertheless, it is thought that several applications of oil, say one or two hours apart, would DESTROYING AND REPELLING MOSQUITOES 93 kill the larger part of larvaj and pupse in such pools. A similar experiment repeated in another ditch gave pre- cisely similar results with one additional point worthy of note. In one of the pools carefully observed, a thin mass of Algse and scum rested over quite an area adja- cent to one of the banks. In it were many larvae and pupae. Into this mass the oil never penetrated, and in my opinion with that current never would, no matter how many applications were made. It would seem then, that the only sure and quick remedy for such places is to spray the oil on the surface. By this method many adults are killed at the same time. If poured into the sewer, several successive applications must be made to be in any degree effective, and even then in pools where there was algal slime it would have little effect. It is evident, that if the sewer pipes empty into pools or bodies of water with no current, the above con- clusions would not apply. FUMIGATING ROOMS TO KILL MOSQUITOES It is often desired to free a house entirely of these insects. The best and most effective way to do this is to fumigate the rooms with some substance which will either stupefy or kill them. Many substances are used by campers and hunters to drive insects away, but for fumigating houses quite different materials are used. Probably sulfur is most universally used, while pyre- thrum, culicide, and a few other substances are occasionally tried. Pyrethrum. — Pyrethrum was originally produced in Asiatic countries only. Now the plant from which it is 94 HOUSEHOLD INSECTS made is grown in California and the product is known as buhach. Buhach, pyrethrum, Persian insect powder, and Dalmatian powder are practically the same thing. They consist of the finely ground or powdered flower heads of certain species of chrysanthemum, Pyrethrum cineraricefolium and P. roseum.1 It is difficult to secure pure pyrethrum from the drug stores. It is apt to be diluted with various substances that have no value as insecticides. However, the pyre- thrum powders are used a great deal for fighting house- hold insects, especially flies and mosquitoes. Usually the powder is blown into cracks and crevices frequented by the pests. The burning of the powder in rooms as a fumigant is also quite often practiced. The powder may be burned on coals or it may be heaped in little conical piles, which when lighted at the top will burn. The odor of the burning pyrethrum is inoffensive to most persons although with some individuals it may cause headache. When burned in a closed room, it will stupefy all of the mosquitoes. It does not actually kill all of them and they have to be swept up and burned. The odor of the burning powder will give relief from mosquitoes on open porches or in open rooms, but in order to receive the benefit one has to sit in the smoke. A pound of the powder to 1000 cubic feet of space has been recommended as necessary to accomplish the desired results. This makes such fumi- gation rather expensive, and because the powder does not actually kill the insects, sulfur is used more extensively. Sulfur. — On account of its cheapness and effectiveness, sulfur is the most desirable fumigating substance for mos- quitoes. The room in which the fumigation is to be done 1 Now put in the genus Chrysanthemum. DESTROYING AND REPELLING MOSQUITOES 95 should be made as tight as possible by stopping the cracks with strips of paper, as explained in a later chapter on bedbugs. The author has been able to burn sulfur very satisfactorily by putting the required amount, 2 pounds to 1000 cubic feet of space, in an iron dish and pouring on top half a teacupful of wood alcohol. The dish con- taining the burning sulfur is liable to become very hot and should be placed on bricks set in a tub containing a little water. The sulfur is liable to boil over and set fire to the floor. The gas kills all of the mosquitoes and is thus very effective. It, however, tarnishes brass, nickel, and gilt, and articles made of these materials should either be removed from the room or covered with paper or cloth. Culicide. — In the great fight against yellow fever in New Orleans a compound of equal parts, by weight, of carbolic acid crystals and gum camphor was found efficient in killing mosquitoes in rooms. It is known as Mims "Culicide." Take one pound of carbolic acid crystals and liquefy by placing the bottle in hot water; take one pound of gum camphor, break into small pieces, place in a one-quart jar, and as the acid liquefies, pour it over the gum camphor, which will be gradually dissolved. When all the acid has been poured over the camphor and the latter has dissolved, there will be one full quart of a slightly reddish, heavy liquid. This is the Culicide, which will remain in this condition indefinitely, if kept covered. Three ounces evaporated in a closed room will suffice to kill all flies, mosquitoes, and other insects in one thousand cubic feet of space. To evaporate, it is necessary to use heat, and an arrange- ment to do this is easily improvised by a section of stove pipe from which triangular pieces are cut at the bottom 96 HOUSEHOLD INSECTS to leave three legs. A series of six holes, near the top, provides for a draft, and a tin pan or dish is set on top of the pipe and holds the Culicide, which is heated by the flame of an alcohol lamp placed at the bottom of the pipe. It will require an ounce of alcohol to completely evaporate three ounces of Culicide in twenty minutes. The Culicide is inflammable, but not explosive. As a matter of safety it will be better to place the apparatus in a tub of water on two or three bricks, so that in case of carelessness there will be no danger of fire. The room to be fumigated should be closed tightly, as recommended above, and should be kept closed for two hours at least. This material will not affect fabrics nor metals, nor are the fumes dangerous to human life. It is not recom- mended that anybody remain within the room while fumigation is going on, but the room can be safely en- tered immediately after opening, and it is quite possible to remain in the room with comfort until the evaporation or fumigation is thoroughly under way. It will be well to use only enough alcohol in the lamp to evaporate the material, so that it will go out when its work is done. The flame should be sufficiently high to reach well up toward the tin dish used, so that evaporation may be rapid. It should not be used so high as to come out through the holes and so run the risk of setting fire to the material. THE USE OF BED NETS In spite of our best efforts there are always a few mosqui- toes in certain regions, but there is one good method of escape from them, and that is by the careful use of a good bed net. If a net is arranged so that it does not hang DESTROYING AND REPELLING MOSQUITOES 97 in folds and is not too low and close to the sleeper, there is little air excluded. The prejudice against bed nets and window screens, because they are thought to exclude a great deal of air, is unfortunate and unfounded. Nets and screens are coming into common use everywhere, especially in the South. The author has slept under a net nine months in the year and the feeling of security it gives is most satisfactory. There are several essentials to success in the use of a good bed net. First it must be free from rents, small as well as large, and long enough to reach the floor on all sides of the bed. Some prefer a short net tucked under the mattress. This is good if the tucking is well done, but too often the net is carelessly arranged and then serves only as a trap. Do not have a net that opens up and down the side. Such a net cannot be made tight enough (except with very great pains) to keep out mosquitoes. Really, a bobbinet bar reaching the floor on all sides of the bed is the only satisfactory net. Care should be taken not to allow mosquitoes to enter the net with the sleeper. The edge of the net must not catch on the bed rail or cover and remain off the floor during the night. A net is not only useful and necessary at home, but it is indispensable when traveling. Hotels, especially those in country towns, often have no mosquito bars on their beds. Hotels are to be dreaded because the very room occupied to-night may have been occupied a few nights previous by a malarious person. If so, the malarial mosquitoes present in the room are liable to be teeming with the malarial germ and the unsuspecting sleeper will 98 HOUSEHOLD INSECTS inevitably become infected by them before morning. It is advisable, in traveling, to carry needle and thread to mend the rents in bed nets ; or, better still, to carry a small light net in one's bag for use where nets are absent or where they are too badly torn to mend. I can do no better than to quote the words of Ross. He says " perhaps our first and best defense against malaria lies in the habitual and scrupulous use of mosquito nets at night. . . . The first care of the resident in the tropics, of the traveler, the sportsman, the soldier, the miner, the clerk, should be for his mosquito net. Wherever he lives, wherever he goes, he should see that his mosquito net is with him, that it is in good order, and that it is properly arranged at bed time." WIRE GAUZE SCREENS AT WINDOWS From his own experience, the author considers wire gauze screens at doors and windows next to bed nets in the prevention of malaria. It is true that the bite of one infected Anopheles will not, as a rule, give as severe a case of malaria as the bites of two or more. Hence, any measure capable of lessening the number of these insects that can gain access to an individual lessens the chances of contracting malaria, and also lessens the severity of the disease if contracted. It is not claimed that wire gauze can be fitted tightly enough to keep out all mosquitoes, but any one who has lived in a well-screened house in mosquito regions knows well the difference be- tween the buzzing swarms of these pests found in out- houses after dark and the occasional ones in dwelling houses. DESTROYING AND REPELLING MOSQUITOES 99 A word should be said regarding the kind of screens to use. In the first place, the wire should be galvanized and should have at least fourteen meshes to the inch, and better sixteen. For protection against the yellow fever mosquito, eighteen meshes to the inch are necessary. The most efficient window screens are those that cover the whole window (Fig. 33) . Such a screen is fitted inside .." FIG. 33. — Screen covering whole window. FIG. 34. — Screen over lower half of window. the casing on the outside of the window and is held on by buttons, as shown in the illustration. The screen can be quickly removed in the autumn and easily replaced in the spring. Of course, this type of screen is suitable only where there are no shutters. The next best type of screen is one covering the lower half of the window and fitted inside of the casing (Fig. 34). This screen has a 100 HOUSEHOLD INSECTS strip nailed along its upper edge on the inside to close the opening between the frame of the screen and the lower edge of the upper sash. It is fastened by two buttons near the top and a hook on the inside at the bottom which catches in a screw eye in the window sill. This arrangement enables one to put the screen on and fasten it from the inside of the house, which is of con- siderable advantage, especially in the case of windows in the upper stories. With this type of screen the upper sash of the window should not be lowered, but the lower sash can be raised or lowered at pleasure. In case of those houses that have shutters the screen is sometimes made to fit the casing on the inside of the window. In this case, the screen fits in front of the lower sash only. The stops on the inside are usually removed and the screen put in place of them. These screens are arranged to slide up and down in order to gain access to the lower sash and to close or open the shutters. With one of these screens the lower sash should always be raised to its full height when opened, else there will be a space between it and the wire, and also between the two sashes through which insects could easily crawl. So-called adjustable screens fitted beneath the lower sash are practically worthless. They never fit tightly enough to exclude mosquitoes, and with most of them house-flies can easily enter. Every window and outside door in the house should be screened. In the Southern states the screens should remain on the year round. The same precaution is also necessary to exclude house-flies. Front doors are often screened while the back door is left unprotected, thus forming a fine place of entrance for mosquitoes. Cellar DESTROYING AND REPELLING MOSQUITOES 101 doors and windows should receive special attention because it is in warm cellars that the adult mosquitoes like best of all to pass the winter. GOING INDOORS EARLY AT NIGHT There has heretofore been a prevailing idea that night air caused malaria. We now know that night air is as pure and health-giving as any air, and that chills and fevers are contracted from the bites of Anopheles mosqui- toes that fly at night, and not from any "miasma" in the air. It is therefore just as important that we remain in the house at night as it ever was. Moreover, it is important that we either go within doors early, before dusk, or very carefully screen our porches. It should be said, however, that Anopheles do bite in the daytime. Nevertheless, they are most numerous at night and do most of their biting about dusk. In hot climates, houses are built with as much porch room as possible, and people are much in the habit of sitting on these unprotected verandas. If malaria is to be escaped, such porches must be screened. COOL SLEEPING ROOMS In many of the Southern states mosquitoes breed and remain active very late in the fall. If sleeping rooms are kept warm, these insects will remain active and virulent for some time. To avoid this, one should not have fires in the sleeping room, except, possibly, for a little while in the early morning at rising time. In other words, mosquitoes should be made to lie dormant by low tem- peratures if possible. 102 HOUSEHOLD INSECTS REPELLENTS FOR ADULT MOSQUITOES Various mixtures, oils, and ingredients are used to repel adult mosquitoes. Oil of citronella is said to be a very efficient protection against adult mosquitoes, but it will not last long, at most, and is not to be relied on for pro- tection during a night of sleep. It is mainly useful while one is sitting on porches or in rooms where mosquitoes are troublesome. Chickens and fowls are often pestered by mosquitoes and the author has seen one instance, at least, where he feels sure that mosquitoes were the cause of" sore heads among a flock of chickens. It would seem advisable to use fish oil containing a little crude carbolic acid in such cases. Miss Mitchell gives the following mixture as the best for general use by human beings ; cedar oil, one ounce ; oil of citronella, two ounces; spirits of camphor, two ounces. She says "a few drops of this on a cloth hung on the bed will keep mosquitoes at a distance, and the efficiency continues for a long time." REPELLING MOSQUITOES BY THE USE OF TREES AND PLANTS Many persons hold that where certain trees or plants grow no mosquitoes will be found. Eucalyptus trees and the castor-oil plant are thought to have peculiar efficacy in repelling mosquitoes. The eucalyptus tree, especially, is recommended for planting in mosquito-ridden localities. This tree is widely grown in California and there, if anywhere, it should demonstrate its use in repel- ling mosquitoes. Quayle who has observed this tree in California and its relation to mosquitoes says : " In the DESTROYING AND REPELLING MOSQUITOES 103 Burlingame section all of the numerous winding avenues are lined with eucalyptus ; there are eucalyptus along the highways, and there are groves of eucalyptus ; yet, where these trees are most abundant it might be said that the mosquitoes are most numerous. . . . During the sum- mer of 1904 we captured in five minutes' sweeping, immedi- ately under eucalyptus trees, a pint cup of mosquitoes." Coyote Point, Cal., is covered with these trees, yet the construction of a hotel there was abandoned because of the mosquitoes. Other observers, who have lived where the eucalyptus grows arid have had an opportunity of actually observing its relation to mosquitoes, declare that it does not repel these insects. All the authentic evidence we have on the subject proves that the eucalyp- tus tree is of no avail in repelling mosquitoes. The castor-oil plant has also been heralded as repugnant to mosquitoes. Howard says this idea was based largely upon the report of Capt. E. H. Plumacher, United States Consul at Maracaibo, Venezuela. He reported that his house in Venezuela, surrounded by plantain and banana trees, had been greatly troubled by mosquitoes. But following the advice of neighbors he planted the seeds of the castor-oil plant among the trees, and the mosquitoes disappeared with the development of the plants. Some of these Venezuelan seeds were planted in New Jersey by Brakeley, but the plants proved of no efficacy in repelling the Jersey mosquitoes. J. B. Smith, also of New Jersey, says, "I put out several groups of them (castor bean plants) in 1902 in my front lawn and next to the porch. They were faithfully tested ; but under the very plants themselves the mosquitoes were a little worse than any- where else." 104 HOUSEHOLD INSECTS Chinaberry trees, which have also a reported charm against mosquitoes, have been shown to be worthless as repellents for these insects. RULES FOR THE PREVENTION OF MOSQUITOES The following measures against mosquitoes for the pre- vention of yellow fever published in 1906 by the Public Health and Marine Hospital Service are so authoritative and so much to the point that it seems eminently worth while to publish them here : — HOW TO PREVENT YELLOW FEVER — NO MOSQUITOES, NO YELLOW FEVER TREASURY DEPARTMENT, Bureau of PUBLIC HEALTH AND MARINE HOSPITAL SERVICE, Washington, July 31, 1905. Note. — The measures herein mentioned were recommended by the Army medical board of 1900, and have been indorsed by the American Public Health Association and by the First International Sanitary Convention of American Republics. They have also been justified by the experiences and observations of the two working parties of the Yellow Fever Institute of this Bureau in Vera Cruz, Mexico, and by the commission of the Pasteur Institute of Paris. France, operating in Rio Janeiro, Brazil. The measures have been tested successfully on a large scale in Havana, Cuba, and during the yellow fever epidemic at Laredo, Texas, in 1903 : THE INFECTION OF YELLOW FEVER IS CARRIED BY MOSQUITOES, AND BY NO OTHER MEANS IS THE INFECTION SPREAD. PERSONS TAKE THE DISEASE BY BEING BITTEN BY MOSQUITOES THAT HAVE PREVIOUSLY BITTEN A YELLOW-FEVER PATIENT. DESTROYING AND REPELLING MOSQUITOES 105 THE MOSQUITOES TO BECOME INFECTED MUST BITE A YELLOW-FEVEK PATIENT DURING THE FIRST THREE DAYS OF HIS ATTACK. THESE FIRST THREE DAYS, THEREFORE, ARE THE MOST LMPORTANT TIME FOR PREVENTING THE ACCESS OF MOSQUITOES TO A FEVER PATIENT. IT IS OFTEN DIFFICULT TO DECIDE DURING THE FIRST THREE DAYS WHETHER A PATIENT HAS YELLOW FEVER : HENCE THE NECESSITY IN THREATENED COMMUNITIES OF PLACING A MOSQUITO BAR IMMEDI- ATELY AROUND EVERY PATIENT WHO HAS FEVER OF ANY KIND, AND FOR THREE DAYS AT LEAST. FACTS ABOUT SCREENING 1. The netting used should have meshes fine enough to prevent the passage of mosquitoes (at least 18-20 meshes to the inch). 2. It is important to screen the windows and doors of the house. It is doubly important to screen the beds of fever patients. 3. Mosquitoes can bite through mosquito nets when any part of the patient's body is in contact with the netting. 4. Frequent examinations should be made to see that there are no torn places in the netting or that no mosquitoes have found a lodgment inside. 5. The netting should be well tucked in to keep mosquitoes from entering. 6. If mosquitoes are found within the netting, they should be killed inside and not merely driven or shaken out. 7. All cases of fever should be promptly reported to the local health officer. Awaiting his arrival they should be covered with a mosquito bar. FACTS BEARING ON MOSQUITO DESTRUCTION 1. Often mosquitoes live in the vicinity in which they breed. They do not fly a long distance. 2. Mosquitoes breed only in water — usually in artificial collec- tions of fresh water. 3. The young mosquito, or wriggler, lives in water at least seven to twelve days. 4. Although the wrigglers live in water, they must come fre- quently to the surface to breathe. 106 HOUSEHOLD INSECTS 5. Coal oil on the surface of the water prevents the wrigglers from breathing. 6. Destroy the breeding places and you will destroy the mos- quitoes. 7. Empty the water from all tubs, buckets, cans, flower pots, vases, once every forty-eight hours. 8. Fill or drain all pools, ditches, unfilled postholes, and the like. 9. Change regularly every day all water needed in chicken coops, kennels, etc. 10. Treat with coal oil all standing water which cannot be screened or drained (1 ounce of oil will cover 15 square feet of surface). The oil does not affect the water for use if the water is drawn from below. 11. Where oil is applied to standing water it must be distributed evenly over the surface. 12. Put fine wire screening over cisterns, wells, and tanks of water in everyday use. 13. Places in which it is undesirable to put oil, such as watering troughs for stock, lily ponds, etc., can be kept free from wrigglers by putting in goldfish or minnows. 14. Clean away all weeds, grass, and bushes about ditches, ponds, and other possible breeding places, since these afford a hiding place for the mosquitoes. 15. Clean up vacant lots and back yards of all cans, tins, bottles, and rubbish. 16. First do away with, or treat, all places where mosquitoes are known to breed, and then begin to work on places where they might breed. 17. Inspect and treat with coal oil, gutters, culverts, ditches, manholes, catching basins, etc., along the roadside. Manhole covers should be screened. 18. Houses should be cleared of mosquitoes by burning 1 pound of insect powder or two pounds of sulfur to 1000 cubic feet of space. The mosquitoes will fall to the floor and should be collected and burned. 19. Success in mosquito destruction depends upon the cooperation of the members of the entire community. 20. While the infection of yellow fever is carried by a single DESTROYING AND REPELLING MOSQUITOES 107 species of mosquito (the Stegomyia), to insure its destruction it is necessary to destroy all mosquitoes. In places liable to yellow fever both individuals and communities have an effective method of protecting themselves, as indicated above. Use the mosquito bar at once over all cases of fever until the danger from yellow fever has passed. Destroy all mosquitoes. WALTER WYMAN, Surgeon-General. CHAPTER V THE COMMON BEDBUG Cimex lectidarim THE bedbug is apparently as old as man himself, and records seem to show that this parasite has been man's bedfellow as long as human beings have slept in beds. Very likely the bedbug was a companion to the cave man long before such comparatively modern sleeping arrange- ments as beds were ever dreamed of. At any rate, the Romans knew it well and gave it the name Cimex, while Pliny wrote regarding its medicinal qualities and especially recommended it for snake bites. Seven bedbugs mingled with water were a dose for a man while four were sufficient for children. Jame's Medical Dictionary tells us that the smell of them will relieve " hysterical suffocation." It is said that in certain portions of this country, inhabitants used to give bedbugs for fever and ague. Perhaps they had this as an excuse for allowing the pests in their houses. It has gone with man wherever the latter' s colonizing instincts have led him, and it came to America, very likely, with the early colonists. Kalm recorded this pest as abundant among the English colonies in 1748, but says it was unknown among the Indians. NAMES BY WHICH IT IS KNOWN The general name bedbug is given to this insect all over the United States and the name is a most appropriate and 108 THE COMMON BEDBUG 109 descriptive one. In the South, at least in Mississippi and parts of Texas, it is invariably called the "chinch." In New York they are often called "redcoats," while in Baltimore they are given the aristocratic and, at the same time, rather descriptive name "mahogany flat." An old English name for it was "wall louse." DESCRIPTION OF THE BED 4 m The bedbug is a member of a v« sects known as Hemiptera. The squash bugs are familiar members of this group and near relatives of the bedbug. The stink bugs, squash bugs, and bedbugs have certain glands in the body that secrete an oily, volatile, and ill-smelling fluid. No doubt, in the stink bugs, squash bugs, and others this fluid serves as a means of protection and oftentinn by their enemies, the the bedbug there is as a protective weap from some remote ar presence of the be— "buggy" odor. , with egg-case (XI); trap for cockroaches; The bedbug h, bedbug (X 8), below. 110 HOUSEHOLD INSECTS (Fig. 35). The under lip has become greatly lengthened and the edges rolled upward until they nearly meet on top, thus forming almost a closed tube that constitutes the so-called beak. Inside this tube are four long, slender, thread-like organs that move over each other ' ''jfif, alternating motion that enables them to *ate the flesh and set the blood free. The a tube to conduct the blood to the THE bedbug is apj, records seem "to show bedbug is flat and wide (Plate II), a bedfellow as long as h, wonderfully well to the places it has Very likely the bedbug * The cracks and crevices of bed- long before such compart-^ protective retreats for an insect ments as beds were ever tMoreover, the bedbug has no large Romans knew it well and gan(j encumber its retreat. It is Pliny wrote regarding its mecrs of the bedbug had wings but recommended it for snake bit, flightless life of so many ages Seven bedbugs mingled with become lost through disuse. while four were sufficient for >f wingS) for they have not Dictionary tells us that the sleft of the wings are simpiy " hysterical suffocation." It is sfcnd it is fortunate that they of this country, inhabitants used with which to flv> for then and ague. Perhaps they had this control. the pests in their houses. It has gone with man wherever instincts have led him, and it came trHE BEDfiUG with the early colonists. Kami re3eperj for good nouse_ abundant among the English colonies ^s^.s on ^nejr beds to was unknown among the Indians. -jsned m ner house. NAMES BY WHICH IT IS KNC. ^t in by the washer- The general name bedbug is given to th jen bedbugs come the United States and the name is a most . 108 PLATE II t Cockroach, croton-bug, with egg-case (XI); trap for cockroaches; bedbug (X 8), below. THE COMMON BEDBUG HI in on the weekly laundry and has seen them hiding away among the crevices of the clothes basket. In several in- stances, the writer has seen these insects on the white spread of a bed on which the clean clothes have been laid by the laundress. This is a source of infestation that has to be constantly watched. If the members of a family travel a great deal they are liable to bring the pest home in their trunks and hand- bags. Guests that have been traveling and stopping at various hotels often unwittingly become the source of infestation by bringing the pest in their baggage. In towns and cities, where houses are built close to- gether, the bedbug will sometimes actually migrate from one house to another along walls and pipes. This is especially liable to happen where one house has been vacant for some time and the parasites have been deprived of food. Marlatt says the insect " will often continue to come from an adjoining house, sometimes for a period of several months, gaming entrance daily." THE FOOD OF THE BEDBUG Apparently the bedbug naturally chooses human blood in preference to all other food. In fact, the author is unable to find conclusive evidence that the bedbug will accept any other substance than blood as food. Some writers maintain, however, that this insect can subsist for a time upon the juices it may be able to extract from moist wood or from moist accumulations of dirt in cracks and crevices of floors and walls. Indeed, for that matter, DeGeer kept bedbugs alive and active for a year in a tight box without any food at all. Other investigators have 112 HOUSEHOLD INSECTS kept them alve in vials and pill boxes without food for many months. This would indicate that they could live in unoccupied houses for several months, at least, even if they were unable to obtain blood. It is doubtful if bed- bugs could exist more than one season, say an active summer and a dormant winter, in an uninhabited house where no sources of blood were available in all that time. It is exceedingly interesting in this connection to note the experiments of Girault and Strauss on the host rela- tions of the bedbug to mice. They found that bedbugs, under certain conditions, at least, would attack both recently killed mice and living mice and would gorge them- selves with blood from these animals. It is not too much, in the light of these experiments, to suppose that these insects might eke out an existence in deserted dwellings for a considerable period of time if mice were present to serve as occasional hosts. It has also been shown that the bedbug will thrive upon domestic fowls as hosts and feed upon the cat, dog, rabbit, and other animals. HABITS OF THE BEDBUG These hardly need discussion they are so well known. Of course they frequent beds particularly, but are found, when abundant, in cracks of the floor, behind baseboards, window casings, and even in cracks of the ceiling. Wooden bedsteads, especially the large old-fashioned ones, are most apt to be infested. Iron beds do not afford many hiding places for them and are not universally infested. We have, however, seen them in iron bedsteads and in one case found a colony of 30 or 40 bugs living and THE COMMON BEDBUG 113 increasing in the folds of a bed net along the seam up and down the back. Every now and then a bedbug was seen on the net and killed and then down came the bed for a treatment. Probably the bed had been treated half a dozen times when at last, in sheer desperation, the ento- mologist was called in. We were greatly puzzled at first because the bedstead was apparently free from the pests ; but when told that the bugs were always seen on the out- side of the net the search was begun there with the happy result just given above. These insects procure their food at night, attacking the exposed parts of the body. During the day they remain hidden in the bedstead and in the mattress and about the room. Somewhat colored reports have been written re- garding the sagacity and cunning of this insect to gain access to beds and remain hidden during the day. THE BITE OF THE BEDBUG To many persons it is very irritating and causes swelling and produces large red blotches on the skin. The writer remembers vividly his first and youthful experience with bedbugs in a city boarding house while attending school. In this instance they paid especial attention to his neck which was one mass of red blotches before he knew the cause of his restless and uneasy slumbers. Many people are not sensitive to the bite of this insect and seem never to be aware of its existence, even when present. So far as known, there is no poison secreted in the mouth of the bedbug and the inflammation seems to be due simply to the irritation caused by the puncture. 114 HOUSEHOLD INSECTS LIFE HISTORY There are still several things to learn regarding points in the life history of so common and so widely distributed an insect as the bedbug. C. L. Marlatt in 1896 was the first to give the true life history of the bedbug. Later, in 1905, A. A. Girault contributed considerable data to the life history of this insect. We are yet in the dark concerning the number of eggs desposited by a single female and we do not know positively how many generations there may be in a year. The eggs are white and oval in outline with a rim around the free end and sculpturing over the shell. They are laid in batches of varying numbers in cracks and crevices in the bedsteads or other places in which the bedbugs happen to be. The number of eggs deposited by a single female is not known. Southall, Riley, and others have made the common statement, probably not based on actual observation, that each female lays about four batches of fifty each during the season. Girault actually succeeded in obtaining 111 eggs from one well-fed female between June 17 and August 19. How many she had deposited previous to confinement for the experiment he was, of course, unable to say. Girault's experience with this one bug indicates that the females may continue to lay eggs at different periods throughout the breeding season and that there is only one generation a year. The eggs hatch in six to ten days and the young bugs or nymphs molt five times before they become adults. When first hatched the nymphs are whitish in color, but as soon as possible they feed, when the body becomes red or dark purplish, due to the engorgement of blood. As THE COMMON BEDBUG 115 the nymphs molt and grow they become darker and darker in color. Marlatt pointed out that the periods between the molts vary greatly with the amount of blood the nymphs obtain. Girault showed that well-fed nymphs passed through their molts and became adults in 35 to 48 days, while those poorly fed took from 78 to 156 days for their development. Marlatt says that under the most favorable conditions an average period of about eight days occurs between moltings and between the laying of the eggs and their hatching, thus giving about seven weeks as the period from egg to adult insect. It would seem that ordinarily a bug feeds but once between each molt. In this event, each one punctures its host at least five times before be- coming an adult. The adult female probably punctures its host several times before the egg-laying period is finished. DOES THE BEDBUG INFEST ANIMALS OTHER THAN MAN? Many persons feel very sure that the bedbug is found on swallows and that houses may become infested with these pests from the nests of swallows and swifts. It is true that swallows and chimney swifts are infested with a bug very similar in appearance to a bedbug, but it is a species distinct from the latter. Occasionally, these swallow bugs get into dwellings and cause a great deal of worry to housekeepers. In one case, a correspondent writes that the bugs from swifts that had taken up their abode in the chimney of the house invaded a sleeping room in great numbers and severely attacked the occupant of the bed. In a careful search next day, however, none of the bugs 116 HOUSEHOLD INSECTS could be found in the bed although they were abundant about the floors of the room. This is a very interesting note and if the observations and conclusions of the cor- respondent were correct, there is some ground for worry in connection with these bird "bedbugs." A bug very similar to the bedbug is also found in pigeon cotes and an- other in the nests of the English martin. The true bedbug does, however, occur in poultry houses. It has been found that bedbugs breed in the houses and attack the chickens at night, causing considerable injury. In certain parts of the West, the older inhabit- ants, at least, believe that the bedbug lives on dead or dying cottonwood trees beneath the bark and that they will surely be found in houses built of cotton- wood logs. The early immature stages of another bug belonging to the genus Aradus (Fig. 36) are often found under the bark of cottonwood trees. In these immature stages this insect has no developed wings and greatly resembles a bedbug and is, therefore, mistaken for the latter. In this way, probably, the misconception has arisen that bedbugs live out-of-doors on trees. FIG. 36. — Nymph of a species of Aradus, much enlarged. THE COMMON BEDBUG 117 THE RELATION OF THE BEDBUG TO DISEASE Metschnikoff was probably the first to bring the bedbug under suspicion as a transmitter of disease. Since that time many writers and experimenters have labored hard to prove this insect guilty of graver offenses than that of simply stealing blood from human hosts. The most they have been able to do so far, however, is to show that in one case, at least, the bite of the bedbug formed a starting point for a case of bubonic plague. As a matter of fact, this is really a stronger indictment against the bedbug than, at first thought, might appear. The sores resulting from bedbug bites offer ideal points of entrance for disease- producing organisms and are a source of real danger. Actual and definite proofs of the transmission of disease by the bedbug are difficult to obtain, but suspicion points strongly in that direction. It is supposed that they spread the germ causing Obermeyer's relapsing fever, a disease occurring in Europe. Nuttall succeeded in transmitting this germ through the bite of a bedbug from one mouse to another. It is inferred that if the bedbug can transmit the germ from mouse to mouse, it can also transmit it from man to man. Dutton has also shown, experimentally, that the bedbug may spread typhoid fever. The bugs were infected by feeding on the blood of a person in the acute stage of the fever. The bacilli were retained by the bug in a virulent condition for at least twenty-four hours. In 1907 Patton discovered the parasites of a tropical disease of the Old World, known as Kala-azar, in bedbugs (Cimex rotundatus) that had fed on persons suffering from this disease. He did not demonstrate, however, 118 HOUSEHOLD INSECTS that the bedbug actually inoculated other people with it. It is extremely desirable to avoid the bites of this insect if possible, especially in hotels where beds are occupied by so many different people ; but this is very hard to do, in fact, almost impossible if one travels much. CONTROL OF THE BEDBUG In the first place, iron or brass bedsteads are much more desirable than wooden beds in a fight against this pest. The former offer very few cracks and crevices and what there are may be easily reached. There are several old-fashioned remedies for the bedbug that are efficient weapons in the hands of a persistent and thorough housekeeper. Kerosene oil, gasoline, or benzine will kill bedbugs if forced into cracks and crevices with a feather or with a hand syringe. The treatment must be thorough and should be made several times in succes- sion, allowing intervals of three or four days between applications to give time for any untouched eggs to hatch. A mixture of corrosive sublimate one ounce, alcohol one pint, and spirits of turpentine one-fourth pint, painted in the cracks of a bedstead with a feather, is an old fash- ioned remedy and an effective one. Since bedbugs are sucking insects and are killed by contact, it is hard to see how the corrosive sublimate adds anything to the effective- ness of the remedy. If these pests were biting and chew- ing insects and there was thus some probability of their eating some of the poison, there might be more reason for including it. It is possible that, as its name indicates, THE COMMON BEDBUG 119 the mercuric chloride has more or less corrosive effect when it comes in actual contact with the insect. Boiling water poured over the parts of a bedstead that have been carried where they may be liberally treated will kill both eggs and bugs. Of course, boiling water should -not be used on highly polished and varnished furniture. Sulfur has been used with success by some. Person- ally, the author has not found the burning of sulfur effective, but it seems now that not enough was used. Not less than two pounds to every thousand cubic feet of space should be burned and the room should be tightly closed for several hours. The most effective and, at the same time, most economical method of clos- ing the cracks about windows, transoms, and doors, is to tear old newspapers into narrow strips and soak these thoroughly in water. When thoroughly soaked, these strips may be quickly applied over the cracks and will stick there closely for several hours. Fireplaces, chimney holes and other large openings should be closed with old quilts, sacks, or anything convenient. The sulfur may be burned by putting it in an old kettle, baking pan, or similar dish that is not held together with solder, and setting it on brick or in a pan of cold ashes to keep it from burning the floor. A teacupful of wood alcohol poured directly into two pounds of sulfur and then lighted will serve to burn the sulfur completely and readily. The sulfur may be burned on live coals in an ash-pan. It must be remembered that sulfur fumes bleach certain colors in wallpapers and fabrics and tarnish metals of various sorts. For these reasons, its use is objectionable. 120 HOUSEHOLD INSECTS Sulfur candles for fumigating are now made and are very convenient. They may be burned by setting them on bricks in a tub of water or in pans of wood or coal ashes. Where swifts have taken possession of a chimney and bugs from them have overrun adjacent rooms it would be advisable to exclude the birds from their roosting place. This could be done by securely fastening heavy wire net- ting over the chimney opening. It would also probably be feasible to fumigate the chimney by burning sulfur in it after closing the top opening tightly. Hydrocyanic acid gas. — This is the killing agent, par excellence, for bedbugs and household insects. It is a gas formed by the chemical reaction between potassium cyanide, water, and sulfuric acid, and is a deadly poison to human beings as well as to other animals. However, it can be generated and used in the fumigation of houses, without the least danger, if care and precaution are used in the work. The gas is not inflammable, does not bleach colors, does not injure fabrics in any way, and does not, in general, attack metals, although it will tarnish nickel fixtures. These should be covered with towels or similar articles. Dry food products are not affected, but milk and butter may absorb some of the gas and should be covered. See Chapter XVII for a discussion of the use of this gas. Desiring to know the effect of hydrocyanic acid gas on bugs hidden away in mattresses, blankets, comfortables, and the like, the following experiments were tried : — 1. Three bugs were placed in a perforated pill box and then wrapped in excelsior, three inches all around, and this in turn in some domestic to imitate ticking. 2. Three bugs (one adult, one one-third grown, and one THE COMMON BEDBUG 121 very young) were placed in a similar box and then carefully wrapped in two folds of a thick comfortable. 3. Three bugs (two adults and one one-third grown) were placed in a similar box and carefully wrapped in cotton-batting to the depth of two inches. 4. Two bugs (one adult and one two-thirds grown) were placed in a similar box and wrapped in two folds of a thick woolen blanket. 5. Six bugs were put in a vial 3^ inches deep and one inch in diameter, and the latter stopped with an inch cork which had been punched twice with a pair of dissecting- forceps with curved points. The holes thus made had apparently closed up, owing to the spongy nature of the cork, but it was found afterwards that air could be readily forced through them by placing the cork be- tween one's lips. 6. To serve as checks several bugs in perforated boxes were placed about the room at different heights from the floor. In every box of bugs wrapped in different materials several new-laid eggs were placed to determine the effect of the gas upon the hatching of the same. The room in which the fumigation was done measured 14 X 8 X 8, and contained 896 cubic feet. We used 10 ounces of cyanide, 300 cc. of acid and 600 cc. of water, allowing the room to remain closed 14 hours. We made a slight mistake in our computation, and used 1 ounce more of cyanide than our formula called for. The result was surprising and very gratifying. Every bedbug in every case was killed. The fumigation was done June 1st, and up to June 12th, none of the eggs showed any signs of hatching. 122 HOUSEHOLD INSECTS It is impossible to say whether they were fertile or not, but it is reasonable to suppose that they were. We obtained them by confining a dozen or more adult bugs in a large vial, and on the second day we found eggs in abun- dance. The eggs must have been formed in the females under natural conditions in the bedsteads from which they were taken, and very likely the bugs were fertilized there before we collected the females. REFERENCES TO ECONOMIC LITERATURE ON THE BEDBUG 1773. DEGEER, CARL. — Punaise des lits. Memoires pour servir a 1'histoire des insectes, Stockholm, III, pp. 296-305, pi. 17, figs. 9-15. 1889. RILEY, C. V. — The bedbug. Insect Life, Vol. II, p. 104. 1894. PERKINS, G. H. — Household pests. Eighth Annual Report of the Vt. Expt. Stat., p. 128. 1895. COMSTOCK, J. H. — Manual for the study of insects, p. 140. 1896. BUTLER, E. A. — Household insects, pp. 273-303. 1896. MARLATT, C. L. — Bedbugs, Bull. 4, n. s., Bu. Ent, U. S. Dept. Agri., pp. 32-38. 1896. LUGGER, OTTO.— The bedbug. Bull. 48, Minn. Expt. Stat., p. 222. 1896. OSBORN, HERBERT. — The common bedbug. Bull. 5, n. s., Bu. Ent., U. S. Dept. Agri., p. 157. 1901. HOWARD, L. O. — Life history of the bedbug. Insect Book, p. 289. 1905. GIRAULT, A. A. — The bedbug, life history, habits, etc. Psyche, Vol. XII, pp. 61-74. 1905. GIRAULT and STRAUSS. — The bedbug, Clinocoris lectularius, (Linnaeus), and the fowl bug, Clinocoris columbarius (Jenyns) : host relations. Psyche, Vol. XII, p. 117. 1906. GIRAULT, A. A. — The bedbug, literature, pathogenic rela- tions, etc. Psyche, Vol. XIII, pp. 42-48. 1905. KELLOGG, V. L. — American insects, p. 205. 1906. LOCHHEAD, WILLIAM. — Household insects. Canad. Ent., Vol. 38, p. 66. THE COMMON BEDBUG 123 1907. MARLATT, C. L. — Bedbugs. Ore. 47, Bu. Ent., U.S. Dept. Agri. 1907. HERRICK, G. W. — Fumigation with hydrocyanic acid gas for bedbugs. Canad. Ent., Vol. 39, p. 341. 1909. FELT, E. P. — Control of household insects. N. Y. State Mus. Bull. 129. 1910. GIRAULT, A. A. — I. The effect of quantitatively controlled food-supply on development of the bedbugs. Jr. of EC. Biol., Vol. V, pp. 88-91. 1912. -II. Facts concerning the duration of the different stages of the bedbug. Jr. EC. Biol., Vol. VII, pp. 163-188. For a much more extended bibliography on the bedbug and its pathogenic relations, see the article by A. A. Girault, The bedbug, Cimex kdulariw (Linn.), Psyche, Vol. XIII, p. 42, 1906. ^ CHAPTER VI COCKROACHES Ectobia germanica et al. COCKROACHES are exceedingly annoying from the mere fact of their presence and their disgusting proneness to get into things. Often they become of considerable economic importance because of their destructiveness. Several instances are recorded where they have defaced the bind- ings of books in libraries. The paste with which the bindings of books are put on is very attractive to these insects and in getting at the paste, the cloth and leather bindings are often scraped and defaced. In fact, cockroaches are almost omnivorous, eating cereals, bread, biscuits, and almost any dead animal matter. They occasionally injure leather covered furniture and are said to eat their own cast skins, and even living members of their own species, thus becoming can- nibalistic. It is really in large hotels and restaurants, about baker- ies and on board ships that the cockroach becomes a serious and disgusting pest. Persons in private homes have no adequate notion of the cockroach as a pest. There are reliable accounts of these insects occurring in such numbers on board vessels that the whole supply of ship biscuits was either devoured or put in such a filthy condition that they could not be used as food. 124 COCKROACHES 125 R. H. Lewis, in writing of a voyage taken by him in 1835, gives an interesting account of the damages in- flicted by cockroaches on board his ship in the following words: "The ravages they committed on everything edible was very extensive ; not a biscuit but was more or less polluted by them, and among the cargo 300 cases of cheeses, which had holes in them to prevent their sweating, were considerably damaged, some of them being half devoured, and not one without some marks of their resi- dence." Another traveler, Sells, gives a graphic account of the work of these insects as he saw them in Jamaica. " This is the most annoying of the insect tribes in Jamaica, devouring leathern articles of all kinds which have been used, such as saddles, harness, gloves, boots, shoes, etc. ; they devour the bindings of books after they have been handled, and any perspiration has adhered to them ; they crawl over and eat fruit and vegetables, dropping their egg-cases and leaving their feces and an intolerable stench wherever they travel ; they also eat the corks of bottled wine, cider, and porter, causing the liquid to escape. This may, however, be prevented by dipping the corks in a thick mixture of quicklime and water, the latter being occasionally impregnated with the bitter quassia. They harbor in empty bottles which are rendered not only difficult to clean, but almost impossible to sweeten again. They also eagerly devour parchment, which material is consequently never used for wills, deeds, conveyances, or other legal documents, which the insects would very quickly destroy. They have a great dislike to castor oil, which is accordingly rubbed over boots, shoes, and other leathern articles to protect them from their attack." Like the 126 HOUSEHOLD INSECTS bedbug, cockroaches have a peculiar and disgusting odor wherever they have runways. This is familiarly known as the "roachy" odor. Dishes left standing on a shelf for some time where roaches are abundant are apt to become so impregnated with this odor that food after- wards cooked or served in them tastes unpleasant. Cockroaches are among the oldest insects, geologically speaking, that we have. They existed in great numbers during the coal forming age when the prevailing tempera- ture was warm and the atmosphere full of moisture. Under these conditions the cockroaches developed in numbers and species until, entomologically speaking, this period might be called the age of cockroaches. It will shed some light upon the habits of our present-day roaches if we remember the moist, warm environments under which their ancestors appeared and lived. Most of our domestic cockroaches came originally from tropical regions, very likely from the warmer parts of Asia. They were carried to England and Holland during the sixteenth century in the ships that brought teas, spices, and perfumes from the East. For many years they were found only in seaport cities, but gradually spread among the inland towns. Probably, because of their tropical origin, these insects are not able to stand low de- grees of temperature. Hubbard tells us that the cock- roaches, even in dwellings, were nearly all destroyed in Florida during the severe freeze of 1894 when so many orange trees were killed. On the other hand, there is one species of cockroach that inhabits the huts of the Lap- landers and occurs in such numbers at times that the stores of dried fish put away for the winter are greatly damaged and sometimes destroyed. COCKROACHES 127 HABITS Like the bedbug, the cockroach generally remains hidden during the daytime while the occupants of the buildings are actively about. When the kitchen and pantry are deserted and dark, these insects come forth to forage. If one comes into the kitchen suddenly and turns on the light, the roaches will be seen scampering away in every direction. So abundant do they sometimes become that they actually may be heard rustling over the floors as they scurry away. They prefer warm kitchens, baker- ies, and pantries, where there are usually water pipes, warmth, and food. The croton-bug seems to come with the advent of waterworks. Many inhabitants of Southern towns never saw a croton-bug until within the last few years, during which so many of the progressive towns have installed systems of water supplies. Dozens of inquiries have come to us regarding the little roach which had never been seen until the bathroom fixtures had been installed and the kitchen fitted with water pipes. The flat, thin bodies of roaches fit them admirably for crawling into cracks, behind baseboards, window casings, shelves, and other obstructions. It is in such places that they hide away during the day. Moreover, the protection afforded by these retreats is very effective, for it is exceed- ingly difficult to inject anything into these cracks and crannies with sufficient force or in sufficient quantity to actually hit and kill the roaches. The dark, sometimes almost black, color of roaches affords them protection on their nocturnal foraging expeditions. There are certain redeeming traits in the habits of cockroaches that atone a little for their offenses. They have biting mouth parts, 128 HOUSEHOLD INSECTS and are primarily scavengers and may under certain con- ditions devour and thus remove certain offensive dead animal or vegetable matter. They are also quite an enemy of bedbugs and will con- tribute towards the destruction of this annoying pest. However, the small benefit roaches may confer in both these directions will hardly compensate for their presence in dwellings. Insect Life records a very interesting letter from Herbert Smith, who has traveled widely in the tropics, regarding the habits and numbers of cockroaches in Brazil. He says : — "Cockroaches are so common in Brazilian country houses that nobody pays any attention to them. They have an unpleasant way of getting into provision boxes, and they deface books, shoes, and sometimes clothing. Where wall paper is used they soon eat it off in unsightly patches, no doubt seeking the paste beneath. But at Corumba, on the upper Paraguay, I came across the cock- roach in a new role. In the house where we were staying there were nearly a dozen children, and every one of them had their eyelashes more or less eaten off by cockroaches, — a large brown species, one of the commonest kind throughout Brazil. The eyelashes were bitten off irreg- ularly, in some places quite close to the lid. Like most Brazilians, these children had very long, black eyelashes, and their appearance thus defaced was odd enough. The trouble was confined to children, I suppose because they are heavy sleepers and do not disturb the insects at work. My wife and I sometimes brushed cockroaches from our faces at night, but thought nothing more of the matter. The roaches also bite off bits of the toenails. COCKROACHES 129 Brazilians very properly encourage the large house spiders, because they tend to rid the house of other insect pests." METHODS OF DISSEMINATION The foreign species of roaches, the German roach, Australian roach, and Oriental roach were brought here on ships from the various countries in which these insects were native. The German roach, now so well known by the name of croton-bug, is gradually spreading all over this country. It is called croton-bug because it was first associated with the water system of New York City supplied through the great Croton aqueduct. Very likely this cockroach had been in this country long before, but the water pipes gave opportunity for entrance to the houses and the accom- panying dampness was much liked by the insects. It is a fact that these insects become numerous and greatly troublesome in dwellings as soon as a system of water- works is installed. It is evident that these roaches demand a certain measure of dampness for their successful increase and continued existence. There is no reason to suppose they are brought to a town with the iron pipes ; but the dampness attracts them and affords favorable conditions for their increase. Roaches are often carried from town to town in ship- ments of grain, groceries, and other foods. The author once saw two cockroaches in a tight box containing groceries that had been shipped from Chicago to Missis- sippi. Undoubtedly roaches are carried from one house to another with furniture and supplies. We have, at least, one recorded instance of the un- 130 HOUSEHOLD INSECTS doubted migration of cockroaches from one building to another. Howard records this migration in the city of Washington on a dark, drizzly day in September as follows : "The army issued from the rear of an old restaurant fronting upon Pennsylvania Avenue and marched across the muddy street, undeterred by pools of water, ash heaps and other barriers, directly south to the front of the building opposite. " This building was a machine shop and at the direction of the foreman several of the men took brooms and swept back the advancing horde. They swept until their arms were tired, but were unable to stem the advancing tide. The foreman then directed that a line of hot ashes from the furnace be laid along the brick sidewalk. This proved an effective barricade. The foremost cockroaches burned their antennae and their front legs and the army divided to either side and scurried down into the area ways of adjoining buildings in which they disappeared. The march is said to have continued from two to three hours and many thousands of the insects crossed in this way. A moment's glance, after arriving at the spot, showed me that the insect was the croton bug and that nearly all of the individuals were females carrying egg-cases. "I called at the restaurant and found to my surprise that no house cleaning had been going on and that no special effort had been made by the application of insec- ticides to rid the establishment of the roaches. " It seems then to have been a true migration, a develop- ment of the true migrating habit in the croton-bug." Perhaps it is in this way, under cover of darkness, prob- ably, that dwellings become suddenly infested with these insects. COCKROACHES 131 NUMBERS AND DISTRIBUTION OF COCKROACHES The cockroaches belong to the family Blattidse, which is rather closely related to the family of grasshoppers, or locusts. The family Blattidae contains nearly a thousand known species and it is thought that eventually several thousand more species, now unknown, will be added to the list. Fortunately, most of these species occur in the woods and fields away from human habitations. In the United States only four or five species have become domestic. A few species are found in the fields and woods. In tropical countries, however, the domestic species are numerous, and the so-called wild species are abundant and many of them are striking in color and of large size, one species having a wing expanse of more than six inches. As we have already pointed out, at least one species oc- curs in the far North. Of the four species in the United States that are con- sidered pests, one of them, the "black-beetle" of Europe is commonly said to have come, originally, from Asia. One other, the so-called croton-bug, or German cock- roach, is supposed to be of European origin. As a matter of fact, the origin of these two forms is very obscure and nothing absolutely definite is known about their native home. The third species, the Australian cockroach, is undoubtedly a native of Australia and came to this coun- try in ships. The fourth one, the American cockroach, is a home species native to the tropical and sub-tropical parts of America. Thus it happens that three-fourths of the species of roaches common in our households have been introduced from foreign countries and have already become as injurious as in their original homes. 132 HOUSEHOLD INSECTS THE LIFE HISTORY OF COCKROACHES It is almost an axiom that something unknown remains to be found out about almost any insect. This is certainly true of the life history of cockroaches. Many guesses and astonishing statements have been made regarding the time it takes young cockroaches to reach maturity. It has been said that four or five years are required for some species to pass through their life history from the egg to the adult. We cannot flatly dispute this statement, but with one or two species, at least, we know that the time for this development is much less. Cockroaches have a peculiar and characteristic habit of depositing their eggs. Instead of laying their eggs one at a time, like other insects, they deposit them in batches. The eggs are held within the body of the insects and ind°Sed ln a SOTt °f CaP§Ule °r 6^- case, known as an ootheca (Fig. 37). While in the body of the female the egg-case apparently occupies most of the space within the abdomen. The capsule is more or less bean-shaped and, in case of the Oriental roach, contains just sixteen eggs arranged in two rows. The eggs are more or less outlined within the egg-case by line-like depressions between them. When the egg-case is first deposited it is creamy white in color, but within two or three days it turns to a dark brown nearly like the body of the parent. No very exact observations are known to the author which determine definitely the number of eggs laid by one female roach ; but Seiss confined three females of the Oriental cockroach and observed them to deposit twenty-five cases, an COCKROACHES 133 average of about eight for each one, before they died. The twenty-five capsules were deposited between April 20th and September 6th of the same season. Often the egg-case is not deposited free from the ab- domen at once, but is carried about by the female with the end of the capsule projecting from the posterior end of the body (Plate II). C. V. Riley has said that "The female cockroach carries the egg-case about with her until the young are ready to emerge, when it is dropped." Other observers have found that the egg-cases are not carried by the female more than four or five days at the most. Butler says : "When full the case protrudes from the end of the abdomen of the female, and is carried about by her in this position for about a week, after which it is dropped into a suitable crevice in a warm situation." The observer, Hummel, who watched the life history of the German cockroach, says that the young molted six times before becoming full-grown and that they spent from three to five months or even longer in completing their growth. When the nymphs first shed their skins they are soft and whitish in color, but soon harden and change to a darker color. He also states that the mother sometimes assists the young to escape from the egg-case by tearing it open with her jaws, thus providing a means of egress for the young. Marlatt says that the common American roach (Peri- planeta americana) has been carried from the egg to the adult state in the Insectary at Washington and that the young which hatched July 11 reached their full growth between March 14 and June 12 of the following year. In this case, then, nearly twelve months were needed to attain the adult stage. 134 HOUSEHOLD INSECTS It is evident, then, that in the cases which have been actually observed, the cockroach completed its growth in much less time than has commonly been reported. Un- doubtedly the time consumed in the development of young cockroaches depends upon the temperature, amount of food available, and other surrounding conditions. Perhaps a scarcity of food, low temperature, and other unfavorable conditions might combine to retard the development of the nymphs and prolong it for years. DOMESTIC SPECIES OF COCKROACHES There are four principal species of cockroaches that frequent dwellings, other buildings, and ships, and cause the trouble that we have described in the foregoing pages. Probably the best known and most disliked of the four is the German cockroach, or croton-bug, Ectobia germanica, as it is known in this country (Plate II). This species, so abundant in Germany and adjoining countries, is now widely distributed all over the eastern and south- ern parts of the United States and when it once enters a house it increases so steadily that it becomes exceedingly numerous. In a single fumigation of a small pantry and kitchen, the writer has killed over a gallon of these roaches by actual measure. Yet during the daytime they were not in special evidence, but their trails, odor, and general filth were everywhere and in everything. It is the smallest one of the domestic species and the most difficult to get rid of or control. Moreover, it in- creases faster than the others because it lays more eggs at a time and the young complete their growth sooner than those of the other species. It is light brown in color COCKROACHES 135 with two characteristic dark brown lines on the thorax and is about five-eighths of an inch long. Perhaps next to the croton-bug the American cockroach, Periplaneta americana, is the most common and most widely distributed in this country (Fig. 38). It is the largest one of the four and the wings are long and well developed. It is, perhaps, more common in the middle and western United States than anywhere else and formerly was the most troublesome species in these sec- tions. In Texas it is abundant and in some localities, at least, is a great pest, especially in the southern parts of the state. This roach is sup- posed to be of semitropical or tropical origin, and very likely, the conditions in southern Texas are especially favorable to its existence. This species is a well-known in- habitant of feed mills and becomes a nuisance and a costly occupant, because of the food-stuffs it not only eats but renders unfit for market. The basement of a corn mill in Cuero, Texas, was investigated in search of some specimens of the American roach. The basement of the mill was found to be literally alive with them and an abundance of specimens was obtained in a few minutes. They were a nuisance in the mill, but very difficult to get rid of. Kellogg, in "American Insects," says that a friend of his in Mazatlan, Mexico, sent him "quarts of large native American roaches which he readily scooped up from his bedroom floor." He further says that ships come into FIG. 38. — American cockroach. (X 1.) 136 HOUSEHOLD INSECTS San Francisco with the sailors wearing gloves on their hands while asleep, to keep the hordes of roaches from gnawing off their finger-nails. These particular roaches are the most annoying ones on board ships. Moreover, they are responsible for serious injury to books because they like the starchy matter among the bindings. Insect Life records an instance of serious injury by this roach to the bindings of books in the National Treasurer's Depart- ment at Washington. Many of the books in the basement had their backs eaten off although they were up on the higher shelves and in dry situations. Many of the reports, bound in cloth, had been badly eaten both on the backs and covers, thus presenting a cor- FIG. 39. — Oriental cockroach, (x i) roded appearance. It seemed that the American roach went no higher than one or two stories and few of them above the basement. The third species, Blatta orientalis, is known as the Oriental cockroach (Fig. 39) or "black-beetle," the latter name being applied to it in England especially. It is quite widely distributed in the United States, especially in the East and South. It is the most common roach in England and probably came to America with the early colonists. It came originally from the tropical parts of Asia, but has adapted itself to its changed environment with very great success. It is a dark brown roach, becoming almost black in the older female COCKROACHES 137 specimens, and is considerably larger and stouter than the croton-bug. The males and females differ considerably from each other. The males are smaller and not so stout as the females and are furnished with two pairs of shortened wings. The females are wingless, or nearly so, very dark colored, and allow their abdomens to drag almost on the ground when in movement. This species is some- what socialistic in its habits, many individuals living together in peace- able relations with one another. The last species, Periplaneta austral- asice, of importance as a domestic pest, is the Australian roach (Fig. 40), common especially in the Southern states. It resembles the American roach, although it is not so large. Moreover, it has one striking characteristic that serves to distinguish it from the American roach, namely, a bright, clearly defined yellow band on the thorax and a narrow yellow spot on each front wing. It is* not so well and so widely known as a house pest as the croton-bug or the Oriental cockroach, but it is impossible to predict regarding its future development. FIG. 40. — Australian roach. (X 138 HOUSEHOLD INSECTS METHODS OF CONTROL Cockroaches are among the most difficult to control of the household pests. They are difficult to reach because they are especially adapted with their flat, thin bodies for hiding away in inaccessible cracks, crevices, and crannies. Moreover, they are wary and shy of all baits and traps. The croton-bug is the most difficult one of all to get rid of. It seems to display more caution in avoiding traps and baits than most of the others, and as it increases faster, it becomes much more abundant. Fumigation. — Here, again, as with the bedbug, fumiga- tion with hydrocyanic acid gas is one of the most efficient methods we have of fighting roaches. It is used in the same manner and in the same proportions as set forth in the chapter on the bedbug. Unfortunately, the rooms in which roaches are generally found are usually less tightly built and have more openings than the other rooms of the house. Therefore, great care must be exercised in stop- ping the cracks and openings so that the gas will not dis- sipate itself. The author has used this gas in fumigating pantries and kitchens with fine success in most cases. In one or two instances, wrhere the kitchen was very loosely built, as is often the case in warm regions, the roaches escaped through the cracks before the gas, which dissi- pated itself through the same openings, had time to do its work. In small rooms that can be tightly closed and in which no fires or lights are present carbon bisulfide can be used to advantage. This is a clear, colorless liquid with a rather unpleasant odor that evaporates rapidly when exposed to the air. All animals succumb to the effects of COCKROACHES 139 the gas when confined with a sufficient amount of it in a closed space. It is especially suited for fumigating bath- rooms and pantries and may be used in kitchens if there is no fire in the stove. The gas from carbon bisulfide is inflammable and explosive and great care must be exercised in its use. It should be used at the rate of two pounds to every 1000 cubic feet of space. The best way to apply it is to pour it into shallow vessels, tin pans or basins, close the room tightly, and allow it to remain closed from 36 to 48 hours. Time should be given for all of the liquid to evaporate and for the gas to do its work. After the fumigation is completed the doors and windows should be opened and the room thoroughly aired. While the fumigation is going on no light or fire, in any form, should be brought near the room. Buhach. — Another substance used in fumigating for cockroaches is pyrethrum, or buhach. This is a powder obtained by pulverizing the flowers of a plant, pyrethrum, that is now grown in California. Our pyrethrum used to come from Persia and when it arrived here its strength was often greatly weakened, especially after it had stood on the shelves of a store awaiting a purchaser. Now, since it is produced in California, we are much more apt to get it fresh. The American product is sold more commonly under the name buhach. By moistening the powdered buhach it can be molded into cones which, when thoroughly dried in an oven, can be lighted at the tips and will burn slowly and steadily until consumed. The fumes are not poisonous to human beings and they are not explosive, but are often more effective against the cockroach than is the powder applied in the ordinary way. Traps. — Westwood has described a simple trap for 140 HOUSEHOLD INSECTS catching cockroaches as follows: "Various plans have been suggested for their destruction, but the most service- able method is to use a small wooden box, having a cir- cular hole at the top fitted with a glass rim, out of which it is impossible for them to escape. It should be nightly baited and the con- tents thrown the next morning into scalding water." FIG. 41. — Cross-section of a roach trap. In Fig. 41 a cross-section of such a trap is shown. A straight lamp chimney sus- pended firmly in a hole in the middle of the cover serves for the glass rim. The upper end of the chimney should be set just flush with the cover. Pieces of cake, cheese, or similar attractive bait may be placed in the bottom of the box to lure the roaches. Inclined strips of paste- board or thin boards placed against the box as shown in the figure will afford easy access for the roaches to the traps. When once the insects have entered such a trap they cannot escape. Certain ex- perimenters claim to have had fine success in catching roaches with this style of trap. In Fig. 42 is shown a simple style of trap. It is simply a circular tin box baited with bits of material attractive to roaches and provided with inclined runways to make it easy for the insects to enter. A trap of this kind may be made from one of the ordinary cans in which coffee is often sold. One should select a deep can and use FIG. 42. — Tin box trap for roache COCKROACHES 141 only those that are bright and smooth inside. The roaches after they have once entered the trap cannot climb up the sides of such boxes and escape. Again, in Plate II is shown a somewhat more modern idea of a roach trap. The holes in the side of the box are fitted with cone-shaped tubes, the outer ends of which are just flush with the outer surfaces of the sides of the box. The roaches easily find their way into the box through the cones in search of the food inside, but cannot find their way out. Roaches, in general, are very fond of stale beer and advantage is taken of this, especially in England, to trap them by drowning them in this liquid. Any deep jar will serve for the purpose. It is partially filled with the beer and sticks are then inclined against the jar on the outside and bent over until they project into the beer. The roaches climb up the sticks and slip down into the liquid in which they are drowned. A rather unique way of killing roaches is described by Tepper of Australia. Plaster of Paris, one part, is mixed with flour, three or four parts, in a saucer, and placed where the roaches are abundant. Near by is placed a flat dish containing water, with bridges arranged so that the roaches can easily get to it. They eat of the flour and plaster of Paris and then drink the water. As a result, the plaster of Paris sets in the intestines and kills them. At any rate, they disappear. Powders. — Buhach or pyrethrum is often used as a powder against cockroaches and when it can be procured in a fresh condition and is used persistently much good can be accomplished. It seems to be more effective against the three large species than against the croton-bug. 142 HOUSEHOLD INSECTS However, one application will accomplish little with any of them. It must be dusted over the floor, behind the boxes, on the shelves, and in every other place frequented by the roaches several nights in succession and subse- quently should the roaches appear again. A powder, known as Insectoline, manufactured by the Insectoline Company, Cincinnati, Ohio, has given good results in fighting these insects. The author has used it in kitchens and pantries with satisfactory effect. A large dwelling-house at Stonewall, Mississippi, that had be- come unbearably infested with the croton-bug was rid of them by the use of this powder. The owner was very enthusiastic in its praise. In order to get the best results with this powder it must be applied thoroughly and persistently. Borax. — F. L. Washburn, after failures with several so-called remedies for cockroaches, tried powdered borax and has this to say concerning its value as an exterminator of roaches : " We then turned to powdered borax, using it freely in the kitchen, with marked success. This was sprinkled in cracks about the sink, along the top of base- boards, near the sink, and elsewhere wherever there were cracks which afforded the insects a hiding place. By a generous use of this substance, persisted in for two weeks, the room, in fact, we may say the premises, were entirely freed from this disgusting pest. Others to whom it has been recommended report the same success, and in conversation with other economic entomologists we hear unqualified praise for the 'borax method.' " Whatever powder or other substance is used it must be applied in large quantities over an extended period of time. Moreover, the material must be applied fre- COCKROACHES 143 quently and at short intervals. Persistence and thorough- ness are absolutely essential to the successful control of cockroaches. REFERENCES TO ECONOMIC LITERATURE ON COCKROACHES 1882. LINTNER, J. A. — Remedy for the cockroach. First Rept., N. Y. Ins., p. 343. 1888. RILEY, C. V. — Injury done by roaches to the files in the Treasury at Washington. Insect Life, Vol. I, p. 67. 1895. HOWARD, L. O. — Migration of cockroaches. Insect Life, Vol. VII, p. 349. 1896. SEISS, C. F. — The breeding habits of Periplaneta orientalis. Ento. News, Vol. VII, pp. 148-150. 1896. BUTLER, A. E. — Household insects, pp. 116-146. 1896. MARLATT, C. L. — Household insects. Bull. 4, Bu. Ent., U. S. Dept. Agri., pp. 84-95. 1896. BECKWITH, M. H. — A remedy for cockroaches. Eighth Ann. Rept. of the Del. Expt. Stat., p. 114.' 1897. LUGGER, OTTO. — The Orthoptera of Minnesota. Bull. 55, Minn. Expt. Stat., pp. 177-187. 1902. MARLATT, C. L. — Cockroaches. Circ. 51, s.s., Bu. Ent., U.S. Dept. Agri., pp. 1-15. 1903. WASHBURN, F. L. — Experiments with cockroaches. Eighth Ann. Rept. of the State Ent. of Minn., pp. 162-163. 1903. HOULBERT, G. — Les insectes ennemis des livres, pp. 127- 150. 1904. SURFACE, H. A. — Remedies for cockroaches. Ann. Rept. of the Penn. State Dept. Agri., for 1903, p. 175. 1905. URITTON, W. E. — Books injured by cockroaches. Fourth Rept. of the State Ent. of Conn., p. 215. 1905. KELLOGG, V. L. — American insects, p. 126. 1906. WASHBURN, F. L. — Cockroaches. Eleventh Ann. Rept. of the State Ent. of Minn., p. 72. 1907. COMSTOCK, J. H. — Manual for the study of insects, p. 106. CHAPTER VII FLEAS Pulex irritans, et al. PERHAPS by the time that this comes from the printer nearly a hundred and fifty species of fleas will have been found to exist in the world. Something over one hundred are now known and about fifty have been recorded from this country alone. It seems that we are very rich in species of fleas, and, at times, are richer in individuals than we desire. Fleas occur on a great variety of animals. These insects have been found on the dog, cat, rat, squirrel, woodchuck, opossum, grizzly bear, weasel, mole, mice, and other mammals and on birds. Two species, at least, are occasionally serious pests to the domestic fowl and two species attack man. THE FORM AND STRUCTURE OF A FLEA A flea has a body peculiarly well fashioned for the place in which it has chosen to live. In the first place, its body is compressed, that is, flattened from left to right. When we recall that a flea lives and moves about among hairs set close together we can readily see how much better a com- pressed body is suited for movement among such objects than a wide, flat body would be. In fact, so large an insect as a flea could move with difficulty through a thickly set 144 FLEAS 145 coat of hair if its body were flat and thin like that of a bedbug. In the second place, many fleas have strong spine-like hairs projecting backward from the posterior edges of the body segments. Undoubtedly, these pro- jecting spines catch around the bases of the hairs and serve to prevent the insect from slipping backward and enable it to push steadily forward. If a flea is caught between the thumb and forefinger, it will gradually work forward in spite of our best efforts and finally escape. Fleas do not have wings and are therefore unable to fly. On the other hand, their legs are very long and well fitted for jumping, especially the hind ones. So that the lack of wings does not seriously handicap them in getting around from room to room or from one animal to another. More- over, each foot is furnished with two claws, which enable them to cling tenaciously to the hairs of their hosts. In some interesting experiments made to determine the jumping ability of the human flea, Mitzmain starved a female five days and then measured her jumps made on a smooth surface of wood. The four jumps recorded measured 10.5, 11, 12, and 13 inches, respectively, an average of llf inches. He also determined that a human flea could jump at least 7| inches in a perpendicular di- rection. The eyes of fleas are simple, and in some species, at least, are almost if not quite useless as organs of vision. The mouth of a flea is constructed for piercing the flesh and sucking the blood. The mouth parts are composed of several long, slender organs, three of which serve for piercing and all of them together form the sucking tube. It is a very effective apparatus for obtaining blood from its host. The human flea is exceedingly bloodthirsty, 146 HOUSEHOLD INSECTS and it is an interesting fact that blood is squirted from the anus while it is feeding. KINDS OF FLEAS COMMONLY FOUND IN DWELLING-HOUSES There are two species of fleas that become common in dwelling-houses in the United States and act as a source of irritation. These are the human flea, Pulex irritans, and the cat and dog flea, Ctenocephalus canis. Most of the fleas that we have found infesting dwelling-houses in the East and South have been the cat and dog flea. A pet dog or cat is very liable to become the source of in- festation from this flea. The author has seen dwelling-houses literally overrun with fleas that had originated from a pet cat. In one instance, in which a house had been closed only three or four weeks in the absence of the mistress, but which had remained accessible, in the meantime, to the pet cat, the fleas had become so abundant that one could not stay in the lower rooms with any degree of comfort. That the cat and dog flea is the more common species infesting houses in the eastern United States is also con- firmed by the records of the United States Bureau of Entomology, for Howard says: "Judging from the speci- mens of fleas sent to the Bureau of Entomology of recent years with complaints of houses being infested by them, the human flea, Pulex irritans (Fig. 43), is not the species most likely to occur in great numbers in dwelling-houses in this country, but rather the common cosmopolitan flea of the dog and cat, Ctenocephalus canis (Fig. 44). This holds especially for the eastern United States." On the other hand, the human flea does occasionally FLEAS 147 FIG. 43. — Human flea, much enlarged. seem to frequent houses in the East in large numbers, especially along the Atlantic Coast. For instance, a correspondent from Brooklyn writes that he finds his summer home on Long Island badly infested with fleas and sends some specimens for determi- nation. These proved to be the human flea. In California and along the Pacific Coast the human flea is evidently by far the most abun- dant species found in the abodes of man. Doane gives a list of the fleas collected from human hosts and houses in San Francisco from February to June, 1908. In all, 916 fleas were taken, of which 913 were human fleas and 3 were the common rat flea, C. fasciatus. McCoy and Mitzmain record the fleas taken from 29 different in- dividuals in California in FIG. 44. -Cat and dog flea, much one year ag 337 human enlarged. _ . . fleas and only 5 specimens of other species. This would indicate that Pulex irritans is the normal parasitic flea of man on the Pacific Coast. 148 HOUSEHOLD INSECTS The human flea also occurs in large numbers, at times, on rats, cats, dogs, and in fewer numbers on mice. In fact, it seems quite certain that whenever a house be- comes infested with human fleas, the rats in that house will also be found abundantly infested with them. When dwellings are left vacant for a length of time they are often found, on the return of the occupants, abundantly infested with fleas. This has led to the popu- lar opinion that these insects are sometimes spontaneously generated. Evidence seems to show that, under normal conditions, mammalian blood is necessary for the pairing and oviposition of adult fleas. On the other hand, it seems to have been fairly well established by different observers, that adult fleas can increase in deserted dwellings for some time without the necessity of the normal supply of food. Larvae of fleas have been found in sweepings from the cracks of floors in deserted houses and adult fleas bred from them. In the light of these facts, it is not surprising that a vacant house often becomes badly infested with these insects. OTHER FLEAS FOUND OCCASIONALLY ATTACKING MAN In India and other countries where the plague occurs, the flea (Lcemopsylla cheopis) is the common flea on rats and it has come to be known as the plague flea. This flea now occurs in the San Francisco Bay region and occasionally attacks man. This is probably the principal flea concerned in carrying the plague. The common rat flea in the United States is a much larger species, Ceratophyllus fasciatus. It is also fre- quently found on man. FLEAS 149 There is another flea (Rhynchoprion penetrans) with peculiar habits and variously known as the "jigger," "jigger flea," "chigoe," and "chique," that occurs in tropical and subtropical America. It attacks man and causes much annoyance and serious injury. It is also found on the dog, cat, sheep, goat, cattle, horses, asses, mules, and even birds. The adult female, after impregnation, burrows into the flesh of the host, especially under the toe nails. Here, the presence of the flea causes swelling and finally ulcera- tion that sometimes becomes very serious in its final effects. The hen flea, Argopsylla gallinacea, occasionally passes to man as a temporary host. THE LIFE HISTORY OF FLEAS The life history of a flea is similar to that of a house-fly in that there are four distinct stages during the full de- velopment of a flea, namely, egg, larva, pupa, and adult. A flea does not pass its whole life history on the host which it infests. Only the mature stage or adult is found on the infested animal, the other stages being spent in quite different situations. The eggs of the dog and cat flea are deposited, as a rule, while the insect is on the body of the host. It is probable that in many instances the eggs are deposited on floors, carpets, or cloths upon which the dog or cat may be walk- ing or lying. If laid while the parent flea is on the host, they are not attached permanently to the hairs and do not remain on the body of the dog or cat, but quickly fall off. There are usually numbers of eggs around the spot where 150 HOUSEHOLD INSECTS a flea-infested dog or cat has been lying. We recall a pet dog that came to the room and lay down a few minutes on a piece of dark blue cloth spread on the floor. After the dog had gone the writer noted many white specks on the cloth and on carrying it to the light and examining it carefully with a lens twelve beautiful pearly white flea eggs were found. These, of course, had fallen from the dog during the short time he had been lying on the cloth. The dog received a thorough bathing in a solution of creolin and his kennel, a barrel, was cleaned by burning a large handful of excelsior in it, while the matting upon which the dog had lain was burned. The eggs are white and waxy, plainly visible to the eye, oval in shape, and it would take about forty of them, placed end to end, to reach an inch (Fig. 45). The eggs that fall upon the carpets or floors in a house or on the sleeping cloths of the cats FIG. 45. — Egg of dog flea, and dogs soon hatch into minute, white, worm-like larvae. The body is composed of thirteen segments and the head bears biting mouth parts, but no eyes. The larvae are active, wriggling creatures and they soon crawl away into cracks and crevices, where they feed upon whatever organic matter they can find. In these situations, they attain their growth in ten days to two weeks, under favorable circumstances, and then spin a fine, white, silken cocoon (Fig. 46), often covered with dust, inside of which they change to a quiet, inactive form, the pupa. After a week or ten days, the pupa transforms to the adult flea FLEAS 151 FIG. 46. — Larva of a flea, above; cocoon, below, much enlarged. ready, after feeding, to deposit eggs for another genera- tion. Under the most favorable conditions a generation of fleas may be produced in almost two weeks. It is probable, however, that a longer time is needed under most conditions. Simons, who reared some cat fleas from the eggs, found that the eggs hatched in a little over two days and that the larvae became full grown in seven days. They then spun their cocoons, and after lying quietly in them for eight days more, during which time they changed to pupse, came forth as adults. Thus it took seventeen days for the development of a full generation. Howard relates that in Washington in several rearings of the cat and dog fleas the eggs hatched in from two to four days, the larvse attained their growth in from seven to sixteen or twenty days, and the pupal state consumed from five to fourteen days. Here, again, we see that a single generation may be produced in a little more than fourteen days. Other observers give the period of de- velopment as 4 to 6 weeks and 9 to 10 weeks for the human flea. Evidently the period varies with the tem- perature and other environmental factors. For example, in the colder season, the pupal stage of the human flea may occupy as long as thirty-four days. The following table compiled by Mitzmain shows the cycle of development of fleas in different countries. 152 HOUSEHOLD INSECTS COUNTRY AND SPECIES OP FLEA EGO LABVA PUPA COMPLETE GENERATION India L. cheopis 2 days 1 week 7 to 14 days 21 to 22 days Australia P. irritant 6 days 12 days 14 days 4 to 6 weeks P. irritant 4 to 6 days 11 days 12 days 4 to 6 weeks Ct. cam's 2 weeks 12 days 10 to 16 days 5 to 6 weeks United States Atlantic coast P. irritans\ Ct. canis } 2 to 4 days 8 to 24 days 5 to 7 days 2 to 4 weeks Pacific coast P. irritans 7 to 9 days 28 to 32 days 30 to 34 days 9 to 10 weeks L. cheopis 9 to 13 days 32 to 34 days 25 to 30 days 9 to 11 weeks C. acutus 7 to 8 days 26 to 28 days 24 to 27 days 8 to 9 weeks C. fasciatus 5 to 6 days 24 to 27 days 24 to 26 days 7 to 8 weeks It has been found difficult to maintain just the right degree of moisture for the larvae to thrive. The rearing cages are either too moist or too dry and many of the larvae die before reaching maturity. In his own work with the larvae of the hen flea, Argopsylla gallinacea, the author has had much difficulty in rearing them and was, in fact, unable to rear any to maturity from the few eggs he was fortunate enough to obtain. Mitzmain says that the human flea develops very satisfactorily in material composed of the sweepings taken from cracks in the floor. It is quite probable that the great majority of larvae die under the conditions in which they find themselves. It has long been a question regarding the food of the larvae. Some authors have held that the adult human flea fed its young upon dried blood. This is now thought to be very improbable, for Laboulbene, a French investi- gator, and Mitzmain of the United States have found that the larvae would thrive and reach full growth simply on FLEAS 153 the sweepings of rooms that contained no blood at all. Multitudes of fleas often develop in a house left empty during the summer. It is very probable that the only food found by the larvae under such circumstances is the organic matter in the cracks and crevices of the floor, about the baseboards, in the corners, under the carpets, and in similar places. THE RELATION OF FLEAS TO DISEASE Fleas are now known to be active and menacing agents in the conveyance of disease, especially the bubonic plague. In India, where the bubonic plague often decimates the native inhabitants, careful experiments have demon- strated that the rat flea found in tropical and subtropical countries readily takes this plague bacillus from infected rats and inoculates other rats with it; that the plague bacillus multiplies in the stomachs of fleas and that the bacilli are found in the feces of fleas taken from dead infected rats ; that the bubonic plague does not persist in a locality apart from infected rats ; that the rat flea will make use of man as a host and may be captured in large numbers on men in houses infested with rats ; and, lastly, that evidence proves the rat flea as the trans- mitting agent of bubonic plague infection from rat to man. Verjbitski, as a result of an important series of experi- ments that he made in 1902 and 1903, comes to the follow- ing conclusions, among others, concerning the relation of fleas to the bubonic plague : — "All fleas and bugs which have sucked the blood of animals dying from plague contain plague microbes. 154 HOUSEHOLD INSECTS "The vitality and virulence of the plague microbes are preserved in these insects. "The numbers of plague microbes in the infected fleas and bugs increase during the first few days. "The feces of infected fleas and bugs contain virulent plague microbes as long as they persist in the alimentary canal of these insects. "Infected fleas communicate the disease to healthy animals for three days after infection. "The injury to the skin occasioned by the bite of bugs and fleas offers a channel through which the plague microbes can easily enter the body and occasion death from plague. "Crushed infected bugs and fleas and their feces, like other plague material, can infect through the small punctures of the skin caused by the bites of bugs and fleas but only for a short time after the infliction of these bites. "Human fleas do bite rats." The many investigations that have been made of the relations of fleas to the bubonic plague by different plague commissions and individuals point to the definite con- clusion that rats and fleas, are, at least, the most im- portant factors in the spread of the disease. The bubonic plague is probably, primarily, a disease of rats and only secondarily a human disease. Epidemics of the plague seem to be usually preceded by this disease among the rats of that locality. San Francisco, in her late fight with the plague, gave a great deal of attention to controlling the rats, basing her method of work upon the foregoing ideas of the relation of rats to the disease and the relation of fleas to rats and to man. The results of the fight were eminently successful FLEAS 155 and certainly serve to strengthen the soundness of the theory. Fleas have also been suspected of bearing some relation to the dread disease, leprosy. The bacilli of leprosy have been found in the intestines of certain fleas, and it seems quite possible that the fleas might carry the bacillus to a human host. However, no definite proof of any re- lation between leprosy and these insects has yet been ad- duced. Baker has pointed out that the rat fleas found by him in Cuba are quite closely related to the human flea and might, therefore, bite human beings quite readily. He also found that rats in a leper hospital in Cuba often had sores on them very similar to leprous sores, and argues that the fleas might convey the bacillus from rats to man. It has also been found that the dog flea is the inter- mediate host of the dog tapeworm, Tcenia canina. When fleas containing the immature stages of the tapeworm were fed to dogs the development of the tapeworm in the dog followed in all cases. METHODS OF CONTROL It follows from what has been said regarding the kinds of fleas found in houses and their rate of increase that pet dogs and cats must be gotten rid of or must be kept clean and free from these pests. These animals may be kept free from fleas by frequently bathing them in a solution of creolin and by paying special attention to their sleep- ing places. A dog or cat should be provided with a sleep- ing cloth or rug and this should be beaten or shaken at least once a week and hung in the sunlight, if possible, 156 HOUSEHOLD INSECTS for a few hours. If infested, the dog kennel should be thoroughly washed inside and out with a 5 per cent solu- tion of creolin. To keep it clean and free from eggs and larvae of fleas it should be washed with strong soapsuds occasionally and once or twice a year carefully white- washed. To free a dog from fleas the animal should be bathed in a 3 per cent solution of creolin made by adding 4 teaspoon- fuls to a quart of water or 4 tablespoonfuls to a gallon of water. For cats, a 2 per cent solution is strong enough, for their skin is a little more sensitive than that of a dog. The animal may be treated by putting the solution on with a brush or rag or by making enough of it for the sub- mergence of the patient. After the application, no more attention is needed nor does the material need to be washed out of the hair. It softens the fur, destroys other vermin as well as fleas, heals scratches or sores in the skin, and will deodorize the animal and destroy obnoxious smells. Pyrethrum, or buhach, if it can be obtained fresh, will kill or stupefy the fleas if it is thoroughly dusted among the hairs of the animal. Usually, the insects will fall from the animal, and they may then be swept up and burned if not already dead. To clear a house of fleas when once infested is often a very strenuous task. In the first place, the source of infestation, if it be a cat or dog, must be removed or freed from the pests. In addition to this, the removal of carpets and a change to rugs are recommended. The larvae of fleas cannot develop in rooms in which all parts of the floors are swept from time to time. Matting and carpets afford fine protection to the larvae of fleas and offer splendid hiding places with plenty of dust containing FLEAS 157 organic matter for their development. No scheme of floor covering could be better for fleas. In severe in- festations nothing but the removal of all floor coverings followed by a thorough washing of the floors with strong soapsuds will avail. Sometimes the persistent use of buhach, in which it is sifted over the carpets, along the baseboards, and in all hiding places for fleas, becomes effectual. But, in some cases, it has utterly failed. Again, sprinkling the carpets and floors with benzine is often successful. Great care should be exercised re- garding fire while benzine is being applied. Where only a few fleas are present in a room they may be caught by spreading a white cloth on the floor, and as they alight on the cloth, attracted by the white color, they may be caught by picking them up one by one on the end of the moistened finger and destroyed. In one instance, a large room was greatly relieved of an infestation of fleas by having a man, with sticky fly paper tied around his legs, walk up and down the room. As the insects were disturbed by the walker they would jump on to the paper and stick fast. In this way hundreds of them were caught. It is said that a thorough spraying of a room with oil of pennyroyal will drive the fleas out. In work in the South the author has had many com- plaints of cases where the whole premises were overrun with an infestation of fleas. This will often happen in a warm country where houses are set up on foundations some distance from the ground and open beneath. Such conditions give opportunity for dogs and cats to range beneath the house unmolested and to become sources 158 HOUSEHOLD INSECTS of wide infestation. Van Dine, entomologist in Hawaii, has had the same experience and his method of treatment is so good that it is quoted here. " (1) If the lawn is infested, cut the grass as close to the ground as possible and burn the refuse. Exposure to the sun and air will be detrimental to the development of the larvae. Keep the lawn well watered. " (2) Clean out and burn all refuse from beneath the infested dwelling, leaving the surface of the ground as bare as possible, and apply an even dressing over the sur- face of lime, sulfur, and buhach at the rate of 20 pounds of air-slaked lime to 3 pounds of powdered sulphur and 1 pound of buhach, thoroughly mixed and dry. Spray the underpinnings of the house and the drives and walks (if the latter are sand, gravel, or dirt) with kerosene emulsion at the rate of 1 part of stock solution of the emul- sion to 10 parts of water. " (3) If dogs are owned, provide a room for them to sleep in and keep cats out of the house. Wash with strong soapsuds the floors of the room where the dogs are to sleep, and sprinkle afterwards, when dry, with a liberal amount of buhach. Use a liberal amount of buhach in places where the dogs have been in the habit of sleeping and remove and burn from such places all refuse, old sacks, matting, etc. Every week or so take the dogs to the room provided for them and brush them thoroughly with a strong, stiff brush. Afterwards collect the result- ing hairs and the bedding and burn or immerse the sacks in hot soapsuds and hang in the sun to dry. Then wash the room out as before and sprinkle with buhach, and return the bedding. The dogs should be washed regularly, a little creolin being added to the water. FLEAS 159 " (4) If the house is infested, sprinkle a liberal amount of buhach beneath all rugs and matting, and under all shelving and cabinets. The following day take all rugs, carpets, and matting out of doors and shake thoroughly and hang in the sun for several hours. Wash the floor with hot soapsuds. Sprinkle buhach beneath the rugs, carpets, and matting when returning them to the house." Many people desire to keep a pet dog, and the following method of getting rid of fleas and still retaining the dogs is given by Henry Skinner of Philadelphia. He says : " In the latter part of May I moved into a new house that had not previously been occupied. No carpet was used and being summer only a few rugs were placed on the floors. A part of the household consisted of a collie dog and three Persian cats. Very soon the fleas appeared, the dog and cat flea, Ctenocephalus canis. ... I tried mopping the floors with a rather strong solution of creolin, but it did little good. Previous experience with pyre- thrum (buhach) was not very satisfactory. Knowing the volatility of naphthaline in warm weather and the irritat- ing character of its vapor led me to try it. I took one room at a time, scattered on the floor five pounds of flake naphthaline and closed it for twenty-four hours. On enter- ing such a room the naphthaline vapor will instantly bring tears to the eyes and cause coughing and irritation of the air passages. ... It proved to be a perfect remedy and very inexpensive as the naphthaline could be swept up and transferred to other rooms. So far as I am concerned the flea question is solved and if I have further trouble I know the remedy. I intend to keep the dogs and cats." 160 HOUSEHOLD INSECTS The following method of ridding a cat of fleas as given in a New York paper is interesting and may be of a good deal of value : — "An excellent way to get rid of fleas is used by a lady in Chicago, who owns some of the best cats in America. She has ready a square of cotton batting and a square of cotton cloth. Placing the cat in the center of the batting, which has been laid over the cloth, she rubs strong spirits of camphor quickly into the fur and then gathers the corners of the batting and cloth tight around the neck of the animal. She has the fine comb ready and a dish of hot water, for the pests, who detest the camphor, will run to the head of the cat, and must be combed out and plunged into the scalding water. Hundreds of them, however, will jump from the cat and lodge in the cotton batting, where their scaly feet stick in the cotton so that they cannot get away. When the fleas cease to run out into the head she judges that they have deserted the cat. The animal is then let out of the batting bag, and the latter carefully carried to the kitchen and deposited in the stove. The scent of the camphor clings to the cat for some time and acts as a preventive. A whole cattery may be cleaned out in this way." L. O. Howard gives the substance of a letter from Miss Adele M. Fielde on a method of getting rid of flees as follows : She states that during a long residence in Southern China, where fleas swarm, even in clean houses, she made her own house immune through many years by dissolving alum in the whitewash or calcimine that covered the interior walls, putting sheets of thick paper that had been dipped in a solution of alum under the mat- ting and scattering pulverized alum in all crevices where FLEAS 161 insects might lodge or breed. Powdered alum, she states, may be sprinkled upon carpets already laid and then brushed or swept into their meshes with no injury to the carpets and with the certainty of banishment to many insect pests, including both fleas and moths. REFERENCES TO ECONOMIC LITERATURE ON FLEAS 1872. LABOULBENE. — Metamorphoses de la puce du chat. — Annales de la Societe Entomologique de France, 1872, pp. 267- 273. 1880. TASCHENBERG, E. L. — Praktische Insekten-kunde, Vol. V, p. 131. 1888. GRASSI and CALAXDRUCCIO. — Centrallblatt fur Bacteriolo- gie und Parasitkunde, III, p. 174. 1888. SIMMONS, W. J. — The metamorphoses of the dog-flea. American Monthly Microscopical Journal for Dec., 1888, pp. 227-230. 1895. GAGE, S. H. — Catching fleas with sticky flypaper. Insect Life. Vol. 7, p. 422. 1896. LUGGER, OTTO. — Insects injurious in 1896. Bull. 48, Minn. Expt. Stat., pp. 158-161. 1896. BUTLER, E. A. — Household insects, pp. 248-272. 1896. HOWARD, L. O. — The principal household insects of the United States. Bull. 4, n.s., Bu. Ent, U. S. Dept. Agri., pp. 24-31. 1896. Mosquitos and fleas. Circ. 13, s.s., Bu. Ent., U. S. Dept. Agri. 1896. OSBORNE, HERBERT. — Insects affecting domestic animals. Bull. 5, n.s., Bu. Ent., U. S. Dept. Agri., p. 141. 1899. NUTTALL, GEO. H. F. — On the r61e of insects, arachnids, and myriapods, as carriers, etc. Johns Hopkins Hospital Reports, Vol. VIII, pp. 14, 17, 49, 119, and 133. 1899. SHARP, DAVID. — Cambridge natural history, Vol. VI, p. 522. 1900. NILES, E. P. — Animal parasites. Bull. 112, Virginia Expt. Stat. 162 HOUSEHOLD INSECTS 1901. HOWARD, L. O.— To rid cats of fleas. Bull. 30, n.s., Bu. Ent., U. S. Dept. Agri., p. 94. 1902. CONRADI, ALBERT F. — Remedies for fleas. Bull. 94, N. H. Expt. Stat. 1903. U. S. Dept. Agri. — Remedies for fleas. Farmers' Bull. 169, pp. 30-32. 1905. THEOBALD, F. V. — Flies and ticks as agents in the distribu- tion of disease. The Proc. of the Assoc. of EC. Biol., Vol. I, Pt. I. 1905. ALBERT, HENRY. — Insects ; the role they play in the transmission of disease. New York Medical Journal, and Philadelphia Medical Journal, Feb., 1905. 1906. JOURNAL OF HYGIENE. — See volumes 6, 7, and 8, for experi- mental evidence regarding different species of fleas as agents in the transmission of the plague. 1907. HOWARD, L. O. — Two new remedies for fleas. Science, Vol. XXVI, Nov. 29, 1907. 1907. BAKER, C. F. — Some notes on leprosy in Havana. Bull. 67, Bu. Ent., U. S. Dept. Agri., pp. 118-119. 1907. COMSTOCK, J. H. — Manual for the study of insects, pp. 490-493. 1908. Verjbitski, D. T. — The part played by insects in the epidemiology of plague. Journal of Hygiene, Vol. 8, No. 2, pp. 162-208. 1908. VAN DINE, D. L. — Remedies for fleas. Annual Report of the Hawaii Station for 1907, pp. 35-37. 1908. HERRICK. G. W. — Notes on the hen flea (Xestopsylla gallinacea). Jr. EC. Ent., Vol. 1, No. 6, p. 355. 1908. DOANE, R. W. — Notes on fleas collected on rat and human hosts in San Francisco and elsewhere. Can. Ent., Vol. 40, pp. 303-304. 1908. MITZMAIN, M. B. — Insect transmission of the bubonic plague. Ent. News., Vol. 19, pp. 353-359. 1908. How a hungry flea feeds. Ent. News, Vol. 19, p. 462. 1908. WHERRY, WM. B. — Fleas on rodents and men on the Pacific Coast. Jr. of the Amer. Med. Assoc., Vol. 51, No. 6, p. 495. 1909. FELT, E. P. — Control of household insects. N. Y. State Mus. Bull. 129, p. 19. FLEAS 163 1909. McCov, G. W. — Siphonaptera observed in the plague campaign in California, etc. Public Health Reports, Vol. 24, No. 29, pp. 1013-1020. 1909. Fox, CARROLL. — The flea in its relation to plague with a symposium of the rat fleas. The Military Surgeon, 24, June, 1909, pp. 528-537. 1909. HOWARD, L. O. — House fleas. Circ. 108, Bu. Ent., U. S. Dept. Agri. 1909. SKINNER, HENRY. — A remedy for house fleas. Jr. EC. Ent., Vol. 2, No. 3, p. 192. 1910. MITZMAIN, M. B. — General observations of the bionomics of the rodent and human fleas. Public Health Bulletin 38. 1910. DOANE, R. W. — Insects and disease, pp. 142-160. Much literature regarding fleas and the plague may be found in the Journal of Hygiene and in the reports of the different plague com- missions. Also see Doane's Insects and disease, pp. 194-199. CHAPTER VIII ANTS, THEIR ACTIVITIES AND INVASIONS OF THE HOUSEHOLD THE ants belong to the same great group of insects, Hymenoptera, that contains the wasps, bees, sawflies, and others ; and, like the honey bee and common wasps, are social in their habits of living. Every one is familiar with ants ; they occur in all lands and all regions, from the dry deserts to the damp forests, from the timberline of mountains to the lowest valleys, and among the dwellings and habitations of man. They seem to thrive in all kinds of environment and multiply enormously, so that they outnumber all other terrestrial animals. THE NATURE OF AN ANT COLONY As we have said, ants are social, that is, they live in colonies or communities where every individual ant works for the good of the whole and not for itself alone. A colony of ants furnishes an illustration of a more perfect communistic society than any ever established by man and perhaps a more amicable one than any he will ever be able to organize. In a typical colony of ants there are at least three kinds of individuals, the queen, the males, and the workers. The queen is not the ruler, but the mother of the colony. Her only business seems to be to lay eggs which hatch into workers and other forms to take the places of those 164 ANTS 165 that disappear or die, thus maintaining the full and con- tinuous strength of the community. When the queen comes forth from the pupal stage she has wings which she retains until after the swarming period. After the swarming flight is over and the queen alights, her wings fall off or are torn off by herself or workers and from that time she remains wingless. In some species of ants there may be modified forms of the queen ; for example, giant queens, dwarf queens, worker-like queens, and other forms. The males, which have wings, exist only to mate with the queens, and after the swarming period is over they eventually die. The males are also often modified into giant males, dwarf males, worker-like males, and other forms. The workers, which are undeveloped females, are wingless and constitute the great majority of individuals that we see running about in the vicinity of an ant nest. The workers are just what their title implies. They do the work of the community, build the nest, keep it clean, care for and procure food for the queen and larvae, care for the eggs, fight the battles, and perform other functions. The workers may exist under several different forms. One especially interesting form has a very large head and strong jaws, thus fitting it for war-like functions. Work- ers thus modified are known as the soldiers. THE STRUCTURE OP ANTS Like other insects, the body of an ant is composed of three chief divisions, head, thorax, and abdomen. The abdomen of all of our common ants, at least, consists of two rather distinct parts ; a slender anterior portion consisting 166 HOUSEHOLD INSECTS of one or two segments that constitutes the pedicel or peduncle and a more robust posterior portion composed of several segments, called the gaster. Moreover, each segment of the pedicel is expanded on the top side and forms a lens or button-shaped knob, a character that distinguishes ants from all other insects. The mouth of an ant is furnished with two pairs of jaws, one pair of which, the mandibles, are very large and strong. It is with these that the ants mine in the earth, wood, or living plant tissues, fight their battles, carry their eggs and young, cut leaves, obtain food, and do many other things. On the head are also borne the two antennae, which are very important organs to the ant. The sense of touch is highly developed in the antennae. Ants have one pair of compound eyes and three simple eyes. The posterior end of the abdomen of the queen and the workers of many of our ants bears a sting, which, in some species, is a very effective weapon of defense. THE NESTS AND ACTIVITIES OF ANTS The nests of ants, in a general way, consist merely of a system of passageways or cavities communicating with each other and connected to the outside world with one or more openings. There are some species of ants that live below the surface of the earth and have no openings from their nests into the air except at the swarming period. The style of construction and the materials used by ants in making their nests vary with the different species and with the environment in which the ants live. Moreover, the nests are very irregular, especially when compared with those of wasps and bees. ANTS 167 The passageways of the nests are enlarged here and there into comparatively large cavities, or chambers (Fig. 47). It is in these different chambers that the activities of the FIQ. 47. — Interior of an ant's nest. colony are carried on. The queen lies deep within the interior of the nest in a dry, dark chamber. Here she is carefully tended and fed by the workers, who bear the eggs 168 HOUSEHOLD INSECTS as they are laid to other chambers and zealously care for them. Many insects never see their young; others may see them, but do not care for them ; others, like the bees and wasps, put food into the gaping mouths of their young, but have no further association with them. The ants, however, stand alone among insects in their very intimate relations with their progeny from the egg to the adult. Some of the chambers in the nest are reserved for the eggs, some for the larvae, and some for the pupae. If, as often happens, the eggs, larvae, and pupae are all in one chamber, then they are each grouped by themselves in separate piles, reminding one, as Lubbock says, "of a school divided into five or six classes." In the simpler and more primitive ants this grouping and separation may not be so distinct. The ants are constantly transferring their young from one part of the nest to another in search of the right degree of moisture and temperature. In the warm part of the day the young will be transferred to near the surface, but at night will be carried down again away from the cool air. The ants are constantly cleaning the young, caring for the eggs to prevent mold from grow- ing on them, helping the callow ants to emerge from their cocoons, bringing food, cleaning, enlarging, and recon- structing the nest, and doing thousands of things con- tributing to the comfort, growth, and happiness of the community. RELATION OF ANTS TO OTHER INSECTS AND PLANTS It has been argued, and many observations have been offered to show that there is a most intimate relation between ants and many kinds of plants. Certain authors ANTS 169 claim that many plants not only offer special inducements to attract ants to them by affording favorable nesting places, but also offer the ants delectable food in the way of a sweet liquid, the floral and extrafloral nectar. In return for the domiciles and the food, the ants are sup- posed to protect their plant hosts from certain insect and other animal enemies. In other words, the relationship is one of mutual benefit or a symbiotic one. It is cer- tainly true that many species of ants make their homes in the hollow stems of plants, in the thorns of acacias which the ants easily hollow out, in cavities in bulbs, leaves, and in the dried seed-pods of plants. It is also true that ants assiduously collect and carry to their nests the sweet nectar excreted by many plants. It is not so clear, however, that these favorable nesting places and the nectar are provided by the plants on purpose to attract the ants, nor is it clear that the ants afford the plants protection from the animal enemies. In other words, more definite proof is needed to show that the relations between ants and plants is a purposely mutual one. On the other hand, the relation of ants to plant-lice, tree-hoppers, and certain scale insects is clearly, in many cases, a mutually helpful one. Especially is this true of the relations between ants and plant-lice. The aphids secrete a sweet liquid known as honey-dew, of which the ants are very fond and which they are active in collecting and carrying to their nests. It can hardly be supposed that the aphids excrete the honey-dew solely for the ants. The liquid is an excretion from the ali- mentary canal and is exuded whether ants are in attend- ance or not. On the other hand, ants are very solicitous in their care of aphids in return for the honey-dew. The 170 HOUSEHOLD INSECTS ants sometimes build "sheds" over the lice for their protection and sometimes take the lice into their own nests to care for them. In the case of the corn-root louse the ants collect the eggs of the aphid in the fall, carry them into their own nests, and care for them all winter. In the spring, the newly-hatched aphids are carried out by the ants and placed in burrows dug beforehand among the roots of certain early food-plants. Later, the ants excavate burrows along the roots of the corn and transfer the aphids to these plants. It is interesting to watch the ants collecting the honey- dew from the aphids. An ant approaches a louse and gently stroking the latter with its antennae, the aphid exudes a drop of the sweet material which is quickly gathered up by the ant. This action may be repeated with three or four of the aphids until the ant has all it desires, when it hurries down the stem of the plant and away to its nest with its load of sweet provender. THE LIFE HISTORY OF ANTS Enough observations have now been made to enable us to say that most, if not all, colonies of ants are started by a solitary queen or occasionally by two queens working together. The queen, after the swarming period, alights, tears off her wings, and digs a burrow in the soil or in decayed wood, forms a small chamber, and then closes the opening. Here she remains until her eggs are laid, and have hatched into small larvae that finally mature into normal but diminutive workers. All this time the queen has taken no food, but has lived and fed her brood on the reserve material in her bodv. The small workers ANTS 171 now begin to enlarge the nest and soon other larger workers are reared and the community begins to multiply and increase. The eggs laid by the queen are small and white and rarely seen by the ordinary observer. These are solicitously cared for by workers and finally hatch into white, footless, soft, grub-like larvae. The larvae are also tenderly cared for by the workers and changed from chamber to chamber in conformity with variations in temperature and moisture. The workers feed the larvae either on food which has been predigested and which the workers. now regurgitate or on bits of dead insects, leaves, or seeds that have been chewed fine. The larvae, after attaining their growth, change to whitish pupae which, in some species, are in- closed in cocoons, while in others they are not. These the workers treat with the same solicitude and care that they show toward their larvae. Observers often mistake the pupae for eggs. Often, on raising up a flat stone one will see the workers running this way and that with the larvae and pupae in their jaws, evidently seeking a place of safety for them. The pupae finally transform to the adult ants of the various forms, workers, queens, and males. ECONOMIC IMPORTANCE OF ANTS Ants, as a whole, may probably be considered as agents in making the earth more habitable for man. Some of the species are neutral, perhaps, in relation to the economic status of mankind. A great many species are certainly beneficial through their action in stirring and aerating the soil. They are constantly burrowing deep into the earth and bringing up the particles which they distribute 172 HOUSEHOLD INSECTS over the surface. Their action in this respect is similar to that of earthworms, the value of which was revealed to us by the classic investigations of Darwin. Ants are also important agents in aiding in the decomposition of organic substances. Their work in this respect is little appreciated or realized because it is invisible. It must be remembered, however, that this work of ants is gradual, incessant, and extends through tremendously long periods of time. Again, ants are great insect destroyers. Their food consists, in great part, of the juices and tissues of dead insects or of insects that they kill. The interesting driver ants of the Old World and the legionary ants of tropical Africa pass through a territory killing and devouring multitudes of living insects, rats and mice. Hunter and Hinds tell us that there are 12 species of ants known to attack the immature stages of the Mexican cotton boll weevil. "In some cases more than half of the immature stages in fields have been found to be destroyed by ants alone. To find 25 per cent so destroyed is not a rare occurrence." On the other hand, certain household species of ants are very annoying and troublesome. Moreover, the leaf- cutting ants of tropical America are very injurious to plants. They will strip a fruit tree of its foliage in a very short time. One species of these leaf-cutting forms (Atta texana) found in Texas attacks cotton, corn, fruit- trees, sorghum, and other plants, and has become of con- siderable economic importance. In some places land is not planted on account of fear of attack by these ants. The mound-building prairie ant (Pogonomyrmex occi- dentalis), distributed over a large part of the western ANTS 173 plains of the United States, has become a distinct pest since man has begun to occupy the prairies. Their large mound-nests in fields of alfalfa or grain become serious obstacles to harvesting the crops. Moreover, when the nests are disturbed the ants emerge in large numbers and attack man and beast, inflicting painful wounds with their stings. In dooryards and lawns and along paths they are liable to attack the passer-by, especially dawdling children. The agricultural ant (Pogonomyrmex barbatus mole- faciens) of Texas may build its mound-nests in fields of alfalfa, corn, or cotton, and since it allows no vegetation to grow over a considerable area around the nest, the in- jury may be quite serious. Moreover, they are pugna- cious and sting intruders severely. Perhaps the most injurious role assumed by ants is their protection and fostering of plant-lice, scale insects, and tree-hoppers. Aphids and scale insects are among our most injurious insect pests and anything that pro- tects them or aids them in increasing may be considered an enemy to man. As a pest, the Argentine ant (Iridomyrmex humilis) stands by itself. Newell says, "As a household pest I venture the opinion that this ant has no equal in the United States." KINDS OF ANTS TROUBLESOME IN DWELLINGS There are several species of ants that may become annoy- ing in dwelling-houses in temperate regions, but perhaps the best-known species are the tiny red ant (Monomor- ium pharaonis) and the small black ant (Monomoriwn 174 HOUSEHOLD INSECTS minimum). Occasionally the large carpenter ant (Cam- ponotus pennsyhanicus) forages in houses, and the pave- ment ant (Tetramorium cespitum) becomes a trouble- some intruder in cities along the Atlantic seaboard. The Argentine ant (Iridomyrmex humilis) wherever it occurs in the United States is probably the worst household pest of all. The little fiery ant (Solenopsis molesta) is also said to invade kitchens occasionally. The red ant. — This ant (Monomorium pharaonis], which is really light yellow in color, is only about one- sixteenth of an inch long (Fig. 48) and, at times, literally swarms in houses, and because of its small size it gets into everything that is not almost hermetically sealed. Hardly any household food prod- ucts come amiss to the red ants. They are especially fond of sugar, sirups, fruit juices, jellies, cakes, fruit pies, and the like. Whenever FIG. 48. — The red ant. , n , (X 20.) one of the tiny workers finds a pleasing morsel or supply of food it immediately informs the rest of the community and they all come quickly trooping to the source of supply. After the colony has found out the existence of a desired bit of food, they swarm over and through it in such numbers that it seems almost a hopeless task to get rid of them. The discouraging part of the problem is that no matter how many we may kill an equal number seems to come to take the places of those destroyed and so long as the queens are allowed to live on undisturbed the workers may con- tinue to come. The French observer Bellevoye tells ANTS 175 us that he gathered 349,500 workers in his rooms in six weeks besides a great many that he killed or threw into the fire without estimating their numbers. All of the workers evidently came from one nest located somewhere in the walls of the house. There are a few redeeming features about the red ant that are worthy of note. Pergande, a careful entomologist and close observer, says that he saw an old building at Meridian, Mississippi, used as a barracks during the war, filled with bedbugs, but invaded by myriads of red ants. He said that several ants would attack a bedbug, pull off its legs, and carry the helpless body away. Every crack and crevice of the rough beds were sought out by the ants and the young and old bedbugs dragged forth and killed. A correspondent of the Florida Farmer and Fruit Grower says that this habit of destroying bedbugs is well known and advises the introduction of red ants into houses for the purpose of exterminating these pests. If the ants would leave when the bugs were killed, all would be well ; but if they should happen to remain as permanent inhabitants of the dwelling, it would be a question whether any gain had been made. Another interesting role played by red ants is that of destroying the white grubs in soil, as related by G. H. Perkins, another observant entomologist. He says, " that a box in which a number of the larvae were living having been discovered by the ants they at once took possession and promptly destroyed every one of them, and this leads to the conclusion that perhaps we are more deeply in- debted than we have been aware to ants for destroying those larvae which inhabit the ground." 176 HOUSEHOLD INSECTS The nests of the red ant may be formed in the walls of a house, under the floors, among trash in old trunks or boxes, or in the lawn or garden just outside the door. The small black ant. — This ant (Monomorium minimum) is smaller, if anything, than the red ant, although there is little visible difference between them in size (Fig. 49). They differ decidedly in appearance, for this one is dark in color and easily distinguished from the red one. The nests of the little black ant are sometimes under stones in the yard, but are more often in the open. The nests have small craters about the entrances made of fine grains of soil. When the nests are opened there will usually be found, among the workers, one or more large females. The black ant is not strictly a house ant, at least not as much so as the red ant, yet it often invades dwellings in FIG 49 —The small considerable numbers and becomes black ant. (x u.) somewhat of a nuisance. The inva- sions are due to the workers who wander some distance from their nests on foraging ex- peditions. The pavement ant. — The pavement ant (Tetramorium cespitum) is an introduced form. It seems to be widely distributed in Europe and constitutes one of the common meadow ants in that country. When introduced in this country it took up its abode in some of our Eastern cities along the Atlantic seaboard, New York, Phila- delphia and Baltimore. Here it established itself by building its nests beneath the pavement or under flagging stones in the yards of dwellings. From these situations ANTS 177 of vantage and nearness to dwellings, the pavement ant has acquired the habit of entering houses and becomes quite as much of a pest, in some instances, as the red ant. Marlatt thinks the pavement ant was introduced into the United States many years ago and believes that it is the species referred to by Kalm in 1748 as often occurring in houses in Philadelphia at that early date. On the other hand, Wheeler points out some reasons for thinking this ant came into this country much more recently. The pave- ment ant is interesting in having several species of parasitic or slave-making ants associated with it and occurring in its nests in Europe. Evidently none of these parasitic species were introduced with their host into America. Marlatt says the colonies of the pavement ant are often very large, for they may frequently be found in masses of a quart or more on turning over stones in yards or on lifting the flagging in paths. The large black carpenter ant. — The large black carpenter ant (Camponotus pennsylvanicus) often becomes an annoying pest in dwelling-houses. It is one of those ants that have the habit of leaving their natural haunts at times and taking up their abode in dwelling-houses. This habit has evidently been assumed since the settlement of America and the erection of buildings here. The natural haunts of the black carpenter ant (Fig. 50) are in decaying stumps, fence posts, logs, and other pieces of wood. We have known them, however, to make their home in the de- caying sill of a porch from which vantage ground they be- came a decided nuisance in the kitchen not far distant. Moreover, they occasionally do serious damage to rafters and beams in buildings. Several observers have shown that the queen of this 178 HOUSEHOLD INSECTS species founds a nest by herself. She selects a favorable place beneath the bark of an old log, for example, and there excavates a small cell. In this she may be found brooding over a few eggs, larvae, cocoons, and small workers. Pricer has also determined that the number of inhabitants of a fully developed nest of the black car- penter ant may contain from 1943 to 2500 workers. There are other species of ants that occasionally become house- hold pests. The tiny thief-ant (Solenopsis molesta) is a native ant that occasionally leaves its natural haunts and builds its nest in houses, where the occupants become pests in kitchens and so.-The large black Pantries' The workers of this ant carpenter ant, enlarged, are very small and yellow and nearly blind. Finally, there is the Argentine ant that stands in a class by itself and is discussed later. GENERAL METHODS OF FIGHTING ANTS Perhaps the first thing to do as a method of prevention is to remove the substance attracting them if this can be done. It can often be placed on a support, the legs of which rest in water covered with a film of oil. Some- times the simple removal of the attractive food to another room may be sufficient. ANTS 179 Another temporary expedient and one which may dis- courage the ants enough to finally stop them from coming is to soak small sponges in sweetened water and place them where the insects are most numerous. The ants will crawl into the pores of the sponges in great numbers and may be killed by dropping the sponge and all into boiling water. This process may be repeated over and over and thousands of the workers destroyed. In cases in which this has been given a thorough and persistent trial, the ants have become so discouraged and bewildered by the sudden loss of so many workers that they have finally abandoned the house entirely. A sirup made by dissolving sugar and borax in boiling water will attract and kill many of the ants. It is said also that camphor, either free or wrapped loosely in paper, and placed around the foods attracting them will drive the ants away. Often the ants may be traced, if carefully watched, and the crack or opening through which they enter discovered. When found, kerosene oil should be squirted into it or it should be tightly plugged with cotton soaked in kerosene. This is often an effective preventive. Ordinary ants may be prevented from reaching tables by setting the legs in cups containing a little water with kerosene oil on the surface. This method does not seem to avail much with the Argentine ant. At least, these ants soon manage to cross the oil often on a causeway formed from the dead bodies of their sacrificed comrades. But against the red ant and the little black ant the film of oil is an effective barrier until it evaporates, when it must be renewed. Cyanide of potassium has been used with marked effect 180 HOUSEHOLD INSECTS against ants in the field. It is a deadly poison and should be handled with great care. If it is powdered fine and scattered over an ant hill, after the latter has been broken up or stirred on the surface, the ants will immediately begin to remove the pieces. In doing so, every one of them that touches the cyanide will be killed. Colonies have been almost exterminated in this way and whenever the colonies of the red ant can be located the cyanide may be used to advantage. It will be found more useful against the normally out-door species, such as the pave- ment ant, carpenter ant, and others. It must be remembered that if fowls are allowed access to the poison and pick up the pieces, they will certainly be poisoned. To obviate this difficulty, it is best to use the cyanide in solution by dissolving it in water at the rate of one-half an ounce or an ounce to a gallon of water. It may then be sprayed over the nest or poured down the openings. This method seems to be quite as effective as scattering it in the powdered form. At least, experi- ments have shown that colonies of some species of ants may be nearly if not quite exterminated in this way. Another very effective method of application consists in placing a pint or more of the solution in hollows dug out at the exits of the burrows of the colony. Ordinary cotton tape treated with corrosive sublimate acts as an effectual barrier to the red ant and other species. The tape is often wound about the legs of tables, tacked along the edges of shelves, and in other places to protect food. The ants will not cross these strips of tape. The prepared tape may be purchased in the larger cities of the South, but the author has never seen it for sale in cities in the North. But since one often gets an ANTS 181 inferior article from the store it is best to prepare it at home. Newell makes a solution of the corrosive sublimate by heating it in water in a granite ware vessel and dissolving all that the water will take up. After this solution has cooled it is filtered. The solution may be filtered, in the absence of filter paper, through a fine clean quality of cotton batting. Simply place a thick layer of the cotton in a funnel and pour the solution in, giving it time to filter through. The tape is then soaked in this filtered solution and pinned up on the wall to dry. Neither the solution nor the tape should be allowed to come in contact with iron, tin, or steel. When the tape is well made it will remain effective for many months, even a year. Tartar emetic mixed with four or five times its volume of sirup and placed about in shallow dishes is an effective remedy against house ants. It is also mixed with sugar at the rate of 1 part tartar emetic, 10 parts sugar, and 100 parts of water. This mixture, poured into individual butter plates and set about in a refrigerator or pantry where ants are numerous, has proven very effective. Naphthalene flakes have also proven an efficient repel- lent against ants. The material is simply scattered about on the shelves and in the corners frequented by the ants. A somewhat fuller discussion of naphthalene flakes and their use against fleas is given in the chapter on fleas. The only method of getting rid of ants permanently is by locating their nests and treating them in such a way that the queen will finally be destroyed. Then no more eggs will be laid and the production of workers will cease. One of the best substances for treating nests to kill the queen and exterminate the workers is carbon bisulfide. 182 HOUSEHOLD INSECTS It is often difficult to locate the nest and sometimes, when found, it will be in an inaccessible situation, for example, in the foundation walls, or under the floor, or in some other equally secluded and protected place. One writer sug- gests that the black ants may be traced to their nests by baiting them with broken pieces of rice, farina, or cream of wheat. The ants will carry these pieces of white food to their nests and may be quite easily traced in this way. Perhaps the red ant may be followed to its home by this means. When the colony is located it may be treated with carbon bisulfide by pouring an ounce or two of the liquid into each of several holes made in the nest with a sharpened stick, after which the mouth of each hole should be quickly stopped with a clod of dirt. A heavy wet blanket thrown over the nest will aid in retaining the gas and tend to make the fumigation more effective. The liquid evaporates quickly and the gas permeates the whole nest, killing queens and workers and exterminating the colony. By attaching a torch to the end of a long pole and extending it out over the nest while the operator stands at a safe distance, the gas may be exploded and the fumes driven into all corners of the colony. If the colony is located in the foundation walls, the problem will be much more difficult and may be impossible of solution. The difficulty will be in reaching the nest with the liquid. If the nest is located under the floor, it may be necessary to remove a piece of the flooring in order to gain access to the colony. In the use of carbon bisulfide, it must be remembered that the gas is inflammable and explosive and no form of fire or light should be brought near the place being fumi- gated. ANTS 183 - C. W. Woodworth says that a very weak solution of arsenic poison such as he has used for the Argentine ant is effective in exterminating common species of ants. The proportions of arsenic and methods of using it are given under the discussion of the Argentine ant. THE ARGENTINE ANT As a pest, the Argentine ant (Fig. 51) stands in a class by itself. Newell, writing of this ant in 1908, says, "As a. household pest, I venture the opinion that this ant has no equal in the United States." Unfortunately, it is not only a household pest, but it has come to be a serious menace to horti- cultural interests because it destroys the buds, blooms, and fruits of certain plants and because it protects and fosters some scale insects that are very injurious to certain plants, notably sugar cane. Again, in some instances it has actually shown itself FlG 51._The queen to be dangerous to human life. Argentine ant, eu- In all probability this ant was first larged' introduced into the United States through the port of New Orleans by way of the coffee ships or other ships from South American points. The ant is a native of America in Brazil and the Argentine Republic and now infests the southern parts of Louisiana, Mississippi, parts of California and probably Texas. This ant builds its nests everywhere, underneath houses, between the walls of houses, in hollow trees, in compost 184 HOUSEHOLD INSECTS heaps, in dooryards under stones, and in many other places. They increase with great rapidity, destroy or drive out other ants with which they come in contact, and penetrate every room, closet, trunk, and corner of a dwelling. They are fond of all sugars, sirups, fruit juices, honey, cakes, fresh meat, blood, lard, cream, dead insects, and other substances. Like other ants, they are fond of the honey-dew secreted by aphids and, as a result, they foster aphids and certain scale insects greatly to the detriment of the infested plants. In Audubon Park, New Orleans, Newell says they destroyed the entire orange crop by eat- ing into the fruit buds and that much of the fig crop in the vicinity of the city was also destroyed. What is more remarkable still, infants have been reported to have been killed by the hordes of these ants crawling into the mouth and nasal passages. Newell relates an instance falling under his personal observation of an infant's being found in great distress during the night from the thousands of these ants that were crawling into its mouth and nostrils. The child had to be submerged several times in water before the ants were driven from its body. It would seem that the possibilities of this ant for committing in- juries of many kinds and against various interests are almost unlimited. It seems that this ant is more persistent than any of our native species and the only permanent way to obtain relief is to destroy the whole colony, especially the queen. Winter trapping. — These ants have a peculiar and rather striking habit regarding their method of passing the winter. In the autumn, there is a tendency for several small colonies to combine into one very large colony which then seeks a suitably protected location for the winter ANTS 185 season. Newell says that he has taken advantage of this habit by providing a dry goods box and filling it with cotton seed and straw, leaving the top open so that the rains will moisten the material and cause decay with a consequent production of heat, especially in the center of the mass. By placing the box in the middle of a city lot or garden nearly all the ant colonies within thirty or forty yards will migrate to it and settle among the warm, decay- ing matter. By throwing a rubber cloth or waterproof canvas over the top of the box in January the whole collec- tion may be killed with a pound of carbon bisulfide. Summer destruction. — Whenever a colony is located in the ground about the lawn or garden, it can be extermi- nated with carbon bisulfide. Colonies occurring under boards or piles of rubbish may be destroyed by spray- ing them with kerosene, crude oil, or boiling water. When a colony is located in an inaccessible situation it may often be coaxed into a location in which it can be easily reached. For example, they are very fond of decaying wood as a nesting place, and if a piece of decayed log with a jar of honey or sugar is placed near the inaccessible situation, the colony will often desert their old nest and move bodily into the log. In this situation every individ- ual may easily be destroyed. Repellents. — The ant tape is effective in preventing the ants from reaching tables and other situations where the tape is so placed that the ants must cross it if they reach their desired goal. Again, Newell says he has had success in driving the ants from a room which they persist in visiting by using a poisoned solution of sugar or molasses. The solution giv- ing best satisfaction was made with white arsenic J gram, 186 HOUSEHOLD INSECTS sugar 20 grams, water 100 cubic centimeters. The arsenic is dissolved in a portion of the water by boiling and the sugar in the remainder. The two portions are then mixed and enough water added to make up for the loss by evaporation in boiling. When the solution was placed about in small dishes, as was described for the tartar emetic, the ants, in some cases at least, gradually left the vicinity. C. W. Woodworth obtained the best results in killing the Argentine ant by the use of a very weak solution of arsenic and sirup. He found that by reducing the arsenic to between one-fourth and one-eighth of 1 per cent that the ants would take large quantities of the poisoned mate- rial to their nests and feed it to the young and the whole nest would be killed by slow poisoning. The most con- venient way to feed the poison was by placing a sponge saturated with the solution in jars with perforated covers. The ants will enter the jars, fill themselves with the sirup, and carry it away. In a later experiment Nickels used sodium arsenite which contains about 57f per cent of arsenic. To make a weak solution, he dissolves a trifle over one ounce of the arsenite in a little hot water. When dissolved it is added to a sweetened solution of 20 pounds of sugar dissolved in three quarts of water. It is necessary to heat the sirup mixture to thoroughly dissolve the sugar. To make a small amount of the mixture, dissolve 3 grams of the arsenite in a little water and add it to a sweetened sirup of 2 pounds of sugar dissolved in J of a pint of water. He says, "We have established that it is possible to exterminate the Argentine ant and to absolutely prevent its spread." ANTS 187 REFERENCES TO ECONOMIC LITERATURE ON ANTS 1888. BELLEVOYE, M. A. — Observations sur Monomorium phara- onis Latr. Annales de la Societe Entomologique de France, Sixth series, Vol. viii, 1888, Fourth trimestre, Bulletin, pp. clxxvii-clxxxi. 1889. RILEY, C. V. — The little red ant. Insect Life, Vol. 2, pp. 106-108. 1890. READ, M. C. — Ant hills and slugs. Insect Life, Vol. 2, p. 252. 1892. PERKINS, G. H. — Red ants destroying white grubs. Insect Life, Vol. 4, p. 391. 1894. CORRESPONDENT. — Bedbugs and red ants. Insect Life, Vol. 6, p. 340. 1894. PERKINS, .G. H. — Household pests. Eighth Ann. Rept. of Vt. Expt. Stat., p. 126. 1895. COMSTOCK, J. H. — Manual for the study of insects, p. 643. 1896. SMITH, J. B. — Economic entomology, p. 396. 1896. BUTLER, E. A. — Household insects, p. 55. 1896. FORBES, S. A. — Insects injurious to the seeds and roots of indian corn. Bull. 44, 111. Expt. Stat. 1896. MARLATT, C. L. — House ants. Bull. 4, n. s., Bu. Ent, U. S. Dept. of Agri. pp. 95-99. 1898. — House ants. Circ. 34, s.s., Bu Ent., U. S. Dept. of Agri., pp. 1-4. 1899. SHARP, DAVID. — Ants. Cambridge Natural History, Vol. VI, pp. 131-183. 1901. CORRESPONDENT. — Remedies against ants. Bull. 30, n. s., Bu. Ent., U. S. Dept. of Agri., p. 97. 1901. HOWARD, L. O. — Insect book, pp. 37-48. 1904. GOSSARD, H. A., and HUME, H. — Insecticides and fungi- cides. Bull. 76, Fla. Expt. Stat., pp. 215-216. 1905. TITUS, E. S. G. — Report on the "New Orleans" ant (Irido- myrmex humilis). Bull. 52, Bu. Ent., U.S. Dept. of Agri., pp. 79-84. 1906. FORBES, S. A. — The corn root-aphis and its attendant ant. Bull. 60, Bu. Ent., U. S. Dept. of Agri., pp. 29-41. 1908. GOSSARD, H. A. — Powdered cyanide of potassium for ants. Jr. EC. Ent., Vol. 1, p. 190. 188 HOUSEHOLD INSECTS 1908. WOGLUM, R. S., and WOOD, WM. — Cyanide as an insec- ticide. Jr. EC. Ent., Vol. 1, p. 348. 1908. WOODWORTH, C. W. — The Argentine ant in California. Circ. 38, Calif. Expt. Stat., pp. 1-11. 1908. NEWELL, WILMON. — Notes on the habits of the Argentine or New Orleans ant, Iridomyrmex humilis. Jr. EC. Ent., Vol. 1, pp. 21-34. 1908. FOSTER, E. — The introduction of Iridomyrmex humilis into New Orleans. Jr. EC. Ent., Vol. 1, pp. 289-293. 1908. PETTIT, R. H. — Note on two insecticidal agents. Tenth Annual Report of the Michigan Academy of Sciences. 1908. PRICER, JOHN L. — The life history of the carpenter ant. Biological Bulletin, Feb., 1908, pp. 177-218. 1909. FORBES, S. A. — Habits and behavior of the corn-field ant. Twenty-fifth Annual Report of the State Entomologist of Illi- nois, pp. 27-40. 1909. NEWELL, WILMON. — The life history of the Argentine ant. Jr. EC. Ent., Vol. 2, pp. 174-192. 1909. Measures suggested against the Argentine ant as a household pest. Jr. EC. Ent., Vol. 2, pp. 324-332. 1910. MARSH, H. O. — Notes on a Colorado ant. Bull. 64, Part ix, Bu. Ent., U. S. Dept. of Agri., pp. 73-78. 1910. WOODWORTH, C. W. — The control of the Argentine ant. Bull. 207, Calif. Expt. Stat. 1910. WHEELER, W. M. — Ants, their structure, development and behavior. Book, 663 pp. 1911. NICKELS, L. J. — Field work in the control of the Argentine ant. Jr. EC. Ent., Vol. 4, pp. 353-358. 1912. HUNTER, W. D. — Two destructive Texas ants, Circ. 148, Bu. Ent., U. S. Dept. of Agri. CHAPTER IX INSECTS INJURIOUS TO CLOTHES AND CARPETS A RATHER large variety of insects attacks fabrics of different kinds, particularly those that contain much wool. Some, however, are impartial in their tastes, while others prefer starched cotton materials. Fabrics that remain undisturbed for some time are most likely to harbor the pests. THE CASE-MAKING CLOTHES MOTH Tinea pellionella et al. Clothes moths have been the bugbears of all house- keepers probably since man began to live in houses and wear woolen and fur garments. The larvae of clothes moths subsist on dried animal matter, such as the dead bodies of insects, dried skins, feathers, wool, and hair. It is quite possible, as Marlatt suggests, that these insects first came into association with man as scavengers living upon the waste animal matter about his rude and unsani- tary habitations. Subsequently, when these convenient supplies of food were removed, the insects were driven to eat the hair and skin of the garments worn by man, later attacking the woolen fabrics as they came into use. Thus the moths have kept pace with man, improving their tastes as man progressed until now they apparently delight most in attacking the finest garments and costliest furs. 190 HOUSEHOLD INSECTS The clothes moths are all introduced species, having come to us from European countries along with our fore- fathers. It is certain that they have existed in this coun- try for many years, for Peter Kalm, a professor in a Swedish university, in a quaint account written in 1771 (3d. ed.) of his travels in North America, tells us that " Moths, or Tinece, which eat the clothes, are likewise abundant here. I have seen cloth, worsted gloves, and other woolen stuffs, which have hung all the summer locked up in a shrine, and had not been taken care of, quite cut through by these worms, so that whole pieces fell out." This description wrould fit conditions that are often found to-day quite as well as a century and a half ago. Not only have clothes moths been long known and recognized in America, but they have been familiar insects to the human race for thousands of years. They are referred to in the Book of Job in the well-known passage, " And he, as a rotten thing, consumeth, as a garment, that is moth-eaten." The Romans were well acquainted with insects that destroyed clothing, and they applied the name Tinea to the caterpillar of any clothes moth, no matter what species, that was found injuring clothes. Pliny speaks of a Tinea with its case and relates how it changes to a chrysalis from which the moth finally issues. Scientists have, therefore, adopted the name, Tineidce, for the family containing the clothes moths and many other closely related moths, all of which are very small, although the name of the family has no connection with our word tiny. The moths belonging to the family Tineidse are all very small and have narrow wings fringed with very long, slender scales. Although small, some of them are really INSECTS INJURIOUS TO CLOTHES 191 very beautiful, surpassing many of our larger moths in brilliancy and richness of coloring. There was always a great deal of confusion concerning the species of clothes moths in this country until Fernald, in conjunction with Lord Walsingham of England, an authority on these insects, settled the question by a care- ful examination and comparison of the specimens found in America. It was determined that there were three species in the United States, evidently all European in origin. It seems that there are no native clothes moths in the United States. The three species are now known as the case-making clothes moth (Tinea pellionella), the webbing clothes moth (Tineola biselliella) , and the gallery- making or tapestry clothes moth ( Trichophaga tapetzella) . There seems to be some difference of opinion as to which is the commoner species of moth in the northern sections of America. Fletcher maintained that he had found the webbing moth much more common in Canada, while Riley finds the webbing moth more common in the South, and the case-making species more abundant in the North. It is certain that in every case in which the work of these insects has been brought to the author's attention in New York many small whitish, silken cases have been found upon the material being eaten. Moreover, these cases have invariably been empty as though they were pupal cases rather than the cases of larvae. The writer is in- clined to believe that these were the pupal cases of the webbing clothes moth, T. biselliella rather than the cases of T. pellionella. If so, then Fletcher seems to be correct regarding the more common species in southern Canada and New York. We have seen the work of these insects especially on fur caps and felt hats. Perhaps, on woolen 192 HOUSEHOLD INSECTS clothing we should find the case-making species more abundant. A more detailed investigation of the life history, habits, and distribution of these moths is much needed. The moths (Fig. 52) of the case-making species are small, measuring only about half an inch from tip to tip of the tiny wings when they are squarely ex- panded. The fore wings are of a shining yellowish- brown color with three distinct dark spots on FIG. 52. -Case-making clothes moth. each Qf them> whye the hind wings are smaller and lighter in color and clothed with a fringe of long slender scales along the posterior margins. Normally, the moths appear in the spring and may be seen flitting about rooms most of the summer. They are apparently attracted more or less by lights and are fre- quently seen flying aimlessly about a lamp at night. The moths, of course, are innocent enough, so far as any actual direct damage to clothing is concerned. Nevertheless much energy is expended by the careful housekeeper in catching and killing them. This energy, however, is not wholly lost, for if the moths are allowed to live, they may deposit eggs for the production of larvae, the real authors of the injury. Undoubtedly, many small, harmless moths are often mistakenly destroyed for the more injuri- ous clothes moths. The tiny eggs of this moth are tucked away among the folds of the garments upon which the larvae are expected to feed. When they hatch, the minute white-bodied INSECTS INJURIOUS TO CLOTHES 193 larva begins, at once, to make a case for itself. The case is a nearly cylindrical tube open at both ends. It is, how- ever, slightly larger in the middle, thus resembling a cigar in shape (Fig. 53). The tube is made of silk and frag- ments of the material upon which the larva is feeding. When feeding, the larva thrusts out its head together with its thorax, which bears the three pairs of legs ; and holding fast to its case with a pair of claspers on the posterior end of the body drags its house along with it wherever it goes. When disturbed, the larva retreats quickly within its case. The larvae feed on woolens, clothing, carpets, furs, and feathers, and are exceedingly FIG. 53. — Case of the destructive. Fernald says that these case-making clothes moth. (X 3.) moths breed during the summer, but not in winter, even when kept in a room warmed by a furnace where the heat was uniform day and night. The moths emerge in June and July, and some even as late as August, yet there is but a single generation annually, so far as I have observed." In the South there are probably more generations a year. The young larva, of course, soon finds its case too small and, as it grows, it has to enlarge the case from time to time. This enlargement is done in a very interesting man- ner. Without emerging from its case, the larva cuts a slit halfway down one side, thus forming a triangular opening. Into this opening it inserts a triangular gore of the woolen material upon which it is feeding. This process is repeated on the opposite side of the case and without leaving its retreat it turns around and repeats the same thing on the other half of the case. Thus the case is enlarged in diameter, but it remains for the larva to o 194 HOUSEHOLD INSECTS lengthen its home. This is done by additions to each end of the case. On the outside the case appears to be com- posed of fibers of the material upon which the larva has been feeding, but inside the case is lined with a soft layer of fine silk. By transferring the larva to different colored materials a curiously parti-colored case may be obtained, for the insect will use the various materials for the enlarge- ments. The larva completes its growth by fall and seeks a secluded place in which to secrete itself and spend the winter in a torpid condition. The larvae have been ob- served to leave the carpets upon which they were feeding and drag their cases up a wall fifteen feet high and fasten them to the ceiling. In the spring, the larvae transform to pupa3 in the cases within which they have lived during the winter. Apparently the pupal stage lasts about three weeks. The moths do not survive long after depositing their eggs. As a usual thing they shun daylight and remain hidden in dark corners. The larva of the clothes moth, despite its secluded life, more or less protected in a case, is sought out by certain tiny but persistent parasites and killed. At least two of these parasites have been reared from the larval cases of this moth. They are Hyperacmus tinice Riley, Ms., and Apanteles carpatus Say. THE WEBBING CLOTHES MOTH Tineola biselliella By some authorities, this species is considered more common in the Southern states than in the North. It is INSECTS INJURIOUS TO CLOTHES 195 certain that it exists in the South in abundance, for the writer has seen many of the naked larva? of this moth on woolen materials. We. recall to mind a college pennant of red felt that was stretched on the wall of a room in Mississippi. This banner was riddled and eaten by the larvae of this species while it rested in that exposed posi- tion on the wall of the room. On the other hand, the webbing or naked clothes moth is certainly abundant in the vicinity of Ithaca, New York. The author has collected the larvaB in abundance from furs and rugs and has taken the moths in houses in April and May. In fact, this is the only species we have taken at Ithaca. Fletcher, as we have already pointed out, found this form more com- mon in Canada than he did the case-making species. Washburn also states that FlG- 54- — Webbing clothes moth, he has come in contact with only this species in Minnesota. These observations certainly indicate the abundance of the webbing clothes moth in the North. This moth (Fig. 54) is usually a little larger than the case-making moth, although it varies a good deal in size. The fore wings are decidedly more yellowish in color — generally described as "shining ochreous" without spots or markings. The hind wings are paler, while the head is reddish. The larvae live upon a great variety of substances such as fur, feathers, wool, bodies of insects, and are occasion- ally found in the upholstering of furniture. The larvae have been observed in England to eat cobwebs found in the corners of rooms and have, in fact, been reared to 196 HOUSEHOLD INSECTS maturity on this rather filmy food. The larvae are also, occasionally, somewhat injurious to specimens in museums and collections, especially to the bodies of insects. F. M. Webster experienced considerable trouble from the larvae of this moth eating into and riddling the bodies of the larger moths in his collection of insects in Ohio. C. V. Riley records rearing the insect from grain infested with the grain moth, Sitotroga cerealella. Evidently the larvae had fed upon the dead caterpillars of the grain moth. Riley and Howard report, in Insect Life, the interesting instance of the larvae having been found in a can of beef meal which had been rejected as being "weevilly." The presence of the larvae of this clothes moth in the beef meal demonstrated its fondness for animal products. The life history of this species has FlG- ui-~Eg^°futhe not been carefully followed, but we webbing clothes j i f moth, (x 25.) have had them under observation tor some time. The egg is oval, pearly white, and very small (Fig. 55), yet visible to the eye. The eggs are desposited on the cloth or material on which the larvae will feed. Eggs were easily obtained by putting moths in cages along with black cloth. One moth laid 44 eggs in a period of 9 days. These hatched uniformly in six days and the larvae from these eggs, which hatched July 31st to August 8th, are only partly grown at this writing, March 22d. They have been kept in a cool room. From some overwintering larvae we obtained pupae from May 15th to May 18th. We obtained an adult moth on May 28th from a pupa formed on the 16th, thus giving a pupal stage of about INSECTS INJURIOUS TO CLOTHES 197 FIG. 12 days. In another instance, the pupal period ap- peared to be about 16 days. It is said there are two generations of this clothes moth in the Northern states, " the first appearing in June from eggs deposited in May, and the second in August and Septem- ber." It would appear, from our studies, that the first generation of moths is from eggs deposited in July and August of the previous year. The larva (Fig. 56) of this moth builds no case, but spins a path of silk wherever it goes. When the larva is full grown it builds a cocoon of silk intermixed with bits of food material. The cocoon is rather rougher and more irregular in outline than that of the case-making moth. 56. — Larva of the webbing clothes moth. (X 6.) THE TAPESTRY MOTH Trichophaga tapetzella The tapestry moth (Fig. 57) is somewhat rare in this country, but apparently common in England. It is con- siderably larger than either of the other two species and much more striking in appearance, owing to the markings on its wings. The wings expand three- quarters of an inch and arc black from the base to the middle, J \ while the outer half is FIG. 57. — Tapestry moth. (X 3.) white, clouded with 198 HOUSEHOLD INSECTS gray. There is a tiny dark spot about midway of the hind edge of each wing and two similar dots with a dark area at the apex of each wing. The hind wings are light gray in color, while the head bears a tuft of long white hairs. The larvse feed on a variety of materials, such as pelts, felts, carpets, horse blankets, and upholstering of carriages. In England the larvae are met with more frequently in out- houses where carriages are kept than in the dwelling-houses. The larvae burrow inside of the material upon which they feed when this is thick enough to enable them to do it. They, therefore, do not construct cases, but they do line their burrows with silk. On account of this borrowing habit these larvae destroy much more material than they eat. Within these galleries it undergoes its transforma- tions to the pupal stage. One of the parasites (Apanteles carpatus) on the case- making moth has also been reared from the tapestry moth. METHODS OF CONTROL First of all, it should be definitely understood that odors emanating from small quantities of various sub- stances like camphor balls, cedar, or naphthalene, have no killing effect on the moths or larvae. Cedar chests or closets lined with cedar are of no avail if eggs are once deposited on clothes stored in them. Apparently, the odor of cedar has some effect in keeping the moths away. The odor of camphor balls also has a repelling effect on the moths. But a few moth-balls placed among clothes in a chest do not prevent injury if eggs are deposited on the garments before the latter are put away. The INSECTS INJURIOUS TO CLOTHES 199 real function and value, then, of cedar chests or closets lies in repelling the moths and keeping them away from the garments. The garments, however, must be free from all eggs and larvae of the moths before being put in chests. Great care must be taken to shake and brush the garments and to hang them in the sun and air until all of the larvae and eggs have been shaken loose and destroyed. In the second place, it should be plainly understood that garments which are often worn are not liable to be injured. It is the clothing and materials that are stored away in closets, trunks, and boxes, for a long time undis- turbed, that are badly troubled. It is under such condi- tions that the moths get an opportunity to deposit their eggs and the eggs have a chance to lie undisturbed long enough to hatch and the larvae have occasion to eat and grow toward maturity. Sunlight and air are among our best available agents of protection from clothes moths. Garments should be hung in the air and sun and then thoroughly brushed and shaken to dislodge the eggs and larvae that may be on them before being put away for the summer. In addition, they should be taken out occasionally (once a month) and brushed, shaken, and aired. The same treatment should be accorded woolen blankets and bedding that are to be stored. After they are once thoroughly cleaned, they may be packed away with a supply of camphor balls distributed among them to repel the moths. It is advis- able to spray the cracks in closets and chests with benzine or gasoline before putting in the clothes in order to kill any eggs or larvae of the moths that may be lurking there. A few old woolen rags or pieces of old furs stored in 200 HOUSEHOLD INSECTS attics but never used are prolific breeding places for these moths and should be taken out and burned. Howard early suggested a method of putting away winter wraps and garments for storage during the summer which is practical and efficient, as we know from experi- ence. He goes to the tailor shop and purchases a few common pasteboard suit boxes and in these the garments to be stored are neatly folded away. Then the cracks around the edges of the cover are sealed by pasting strips of paper over them. This makes a tight box that excludes all moths. The boxes, with care, last several years. Another method of storing clothes is given by a resident of the city of Washington. He has a wooden chest to hold his clothes. In the cover of the chest he has bored a large hole and on the under side of the cover, directly under the hole, he has tied a large sponge. In the middle of the summer he pours a little carbon bisulfide on the sponge and closes the hole with a cork. In this way, he keeps the clothes free from injury. Washburn uses a somewhat similar method. He has a large galvanized iron chest with a tight-fitting cover in which the garments are stored. During the summer he opens the chest occasionally and pours four tablespoonfuls of carbon bisulfide in a saucer on top of the clothes and shuts the cover. In this way he kills whatever larva? may have hatched from eggs desposited on the clothes before they were stored away. Finally, moth proof paper bags of large size are now offered for sale at many drug stores in the larger towns. The bags are large enough to receive skirts and coats without folding and they are so constructed that moths cannot gain entrance to the inside. These bags are safe INSECTS INJURIOUS TO CLOTHES 201 receptacles for the storage of materials liable to be in- fested with moths and will last for years. The upholstering on furniture and carriages is much harder to protect from the moths. Badly infested up- holstered furniture should be placed in a small tight room and thoroughly fumigated with hydrocyanic acid gas. Some good can undoubtedly be accomplished by spray- ing them several times during the summer with benzine or gasoline. These volatile liquids will not stain if they are reasonably clean. Care should be exercised regarding lights because gasoline and benzine are very inflammable. COLD STORAGE Cold storage plants for fruits and meats are common nowadays in all cities and in many small towns. These plants are available for various uses, among which is the storage of furs, rugs, and other valuable woolen goods during the summer season when the owners are out of town. In fact, this is fast becoming in cities a universal way of storing household goods. L. O. Howard reports some careful experiments carried out mainly by Albert N. Read, manager of a cold storage warehouse in Washington, D.C. It was demonstrated in this series of experiments that a continuous tempera- ture of 40 degrees F. is sufficient to maintain the larvae of the case-making clothes moth in an inactive dormant con- dition. It was also shown that the larvae could exist at a temperature as low as 18 degrees if it were continuous. If, however, the larvae were taken out and revived by warmth and then returned to the low temperature they almost invariably died. These results are in accord with the 202 HOUSEHOLD INSECTS general idea that the immature stages of insects are much more subject to the effects of varying degrees of temperature than of even and continuous temperatures. In the light of these experiments, it is suggested that cold storage companies subject the goods in their care to low temperatures for a few days and then allow them to rest for a few days at higher temperatures, followed again by cold. Such variations of temperature would actually kill all the moths and larvse that might be hiding among the goods, after which they could be stored at a uniform temperature of 40 degrees with perfect safety. REFERENCES TO ECONOMIC LITERATURE ON THE CLOTHES MOTHS 1771. KALM, PETER. — Travels into North America, etc. (3d. ed.) (translated by J. R. Foster), Vol. II, p. 8. 1882. FERNALD, C. H. — Clothes moths. Can. Ent., Vol. XIV, pp. 166-169. 1890. RILEY, C. V. — Some insect pests of the household. Insect Life, Vol. II, pp. 211-215. 1893. FLETCHER, JAMES. — Clothes moths. 23d Ann. Rept. Ent. Soc. Ont, pp. 53-58. 1895. Comstock, J. H. — The clothes-moths. Manual for the study of insects, p. 257. 1896. BUTLER, E. A. — Our household insects, pp. 89-102. 1896. HOWARD, L. O. — Some temperature effects on household insects. Bull. 6, n.s., Bu. Ent., Dept. Agri., pp. 13-17. 1896. MARLATT, C. L. — The principal household insects of the United States. Bull. 4, n.s., Bu. Ent., U. S. Dept. Agri., pp. 63-69. 1900. HOWARD, L. O. — A new clothes moth remedy. Bull. 22, n.s., Bu. Ent, U. S. Dept. Agri., p. 106. 1908. MARLATT, C. L. — The true clothes moths. Circ. 36, s.s., Bu. Ent., U. S. Dept. Agri., pp. 1-8. 1910. WASHBURN, F. L. — The clothes moth. 13th Rept. State Ent. Minn., pp. 81-83. INSECTS INJURIOUS TO CLOTHES 203 THE "BUFFALO BUG" OR "BUFFALO MOTH" Anthrenus scrophularics There are two species of beetles in the United States that have come to be known as carpet beetles. Both of them are small insects and not familiar to most house- keepers. It is the larvae or grubs of these beetles that really do the mischief and with these many housekeepers are only too well acquainted. The larvae of one of these carpet beetles has come to be known as the "buffalo bug" or the "buffalo moth" and it is the more common and better known of the two. The other species is known simply as the black carpet beetle. Again, we must make our acknowledgments to the Old World for a comparatively new pest in a new and serious role. It was first noted as a serious pest in this country about 1874, although Henshaw reports it at Cambridge, Massa- chusetts, as early as 1869. In Europe, however, no records are obtainable that show it is especially injurious to carpets, and it is not there considered a serious household pest. At least, it is of so little consequence in European house- holds that it has never attracted any particular attention. It is known in Europe principally as a pest in museums, where it is often found eating the dead bodies of specimens and causing considerable injury. Indeed, it was imported into this country several times in insect collections brought from Europe and has played the r61e of a museum pest in Cambridge, Detroit, and San Francisco. About 1874 it was imported into this country into the cities of Boston and New York, probably simultaneously, in shipments of carpets. Since then it has spread 204 HOUSEHOLD INSECTS westward through Ohio, Indiana, Michigan, Wisconsin, Illinois, and Kansas. The nature of the pest. — In this country this pest is usually known as the " buffalo bug " or '* buffalo moth " (Fig. 58). These names are both misnomers because the pest is not a bug, nor is it a moth. On the contrary, the adult insect is a small beetle about three-sixteenths of an inch long with a general background of black, spotted and speckled with white, and with a red line down the mid- dle of its back. Near each end FIG. 58. — The "buffalo bug (carpet beetle). (X 9.) there are side projections of red. Thus the beetle is rather hand- some in its markings of black, red, and white. Most housewives are, however, not acquainted with the adult beetle, but rather with the active, brown, hairy larva. It is not the full-grown beetle that inflicts the injury to carpets, woolens, and furs, but, like the clothes moth, it is the larva that does the mischief. The beetles feed upon the pollen of flowers and are often found out-of-doors in the spring on spirea, wild cherry, and, later, on milfoil and other plants. When the beetles develop in the house they fly to the window panes in an effort to escape into the open air. Unfortunately, lady-birds (Fig. 59) are often found in the same situations and are many times mistaken for the carpet beetles and killed. The adult carpet beetles, when disturbed, fold up their legs and antennae, feigning death and playing " 'possum." INSECTS INJURIOUS TO CLOTHES 205 Life history of the beetle. — The curiously wrinkled, whitish eggs are laid by the mother beetle among the fibers of the cloth upon which the larvae are feeding or will feed. Here, under favorable circumstances, they hatch in ten days to two weeks and the larvae eat vora- ciously, grow rather rapidly if food is available, and cast their skins, un- der normal con- ditions, about six times. The growth of the larvae is greatly retarded by cold weather or lack of food, but still they manage to exist and live on indefinitely, molting many times and de- vouring their cast skins. The larva is quite character- istic in appearance. It is nearly a quarter of an inch in length and clothed with long brown hairs (Fig. 60). The hairs on the sides of the body are longer than those on the back, while the hairs at the anterior and posterior ends of the larva are longest of all. The larva is active and seems to be eating most of the time whenever food is to be had. After the larva reaches full growth, it transforms, within FIG. 59. — A common lady-bird. (X 13.) 206 HOUSEHOLD INSECTS its last skin, into the pupa. Finally, this old larval skin splits down the back, disclosing the pupa within. Eventu- ally, the pupa transforms into the adult beetle, which often finds its way to the window panes in search of an exit to its out-door food plants. Some studies made here at Cornell indicate that there is only one generation a year in this latitude, although further observations are necessary to settle this point. L. O. Howard says, "there are, probably, in the North, not more than two annual genera- tions." The earliest beetles appear in the fall, usually during October, and continue to appear all winter in well warmed houses and during the spring months. We have found the pupse in houses in January together with freshly emerged beetles. Injuries and methods of control. — FIG. 60. — Cast skin The larvae when abundant may injure of larva of "Buffalo carpets rather seriouslv. They gnaw moth. (X 6.) r . * . ' . holes an inch or more in diameter in the borders where the latter are nailed to the floor. Sometimes the larvae follow a crack in the floor and cut a slit in the carpet almost as neatly as though done with scissors. They are not only injurious to carpets, but attack woolen goods as well, and even wearing apparel in closets, drawers, and trunks. This insect will always be difficult to control in houses having floors completely covered with carpets tightly tacked about the edges. A carpet placed permanently on a floor and allowed to remain there undisturbed for a year INSECTS INJURIOUS TO CLOTHES 207 furnishes ideal conditions for this pest to thrive and increase. As was urged in the case of fleas, so here we would urge a change from carpets to rugs if possible. Where bare floors, covered more or less with rugs, are maintained, the carpet beetles will not find hiding places suited to their development. Moreover, the rugs can be examined without difficulty at any time and, in fact, are usually dusted and aired too often for the larvae to gain a foothold. The tendency among modern homes is toward polished floors and rugs with a consequent diminution of the carpet beetles as a household pest. Where the insect has become well established in a house, nothing but heroic measures and long-continued efforts will avail. Housecleaning should certainly occur twice a year instead of once and should be very thoroughly done, at least, so far as the carpets are concerned. The carpets should be removed, thoroughly dusted and beaten, sprayed with gasoline, and hung in the air and sunlight as long as possible. The floors should be thoroughly washed and scrubbed with soap and water, especially along the baseboards and cracks. It would be of advantage to spray the cracks beneath the baseboards with benzine or gasoline and clean out all the dirt possible from the cracks in the floors and pour in benzine or kerosene oil. Before the carpet is replaced on old floors, the cracks should be filled with a crack-filler, thus eliminating the favorite hiding places for the larvae. In badly infested houses, tarred building paper may be placed beneath the carpets, but the odor from such paper is not always pleasant. The carpet may be very loosely tacked about the edges, thus affording an opportunity to examine it often to see if 208 HOUSEHOLD INSECTS the pests have returned. The following is a good account of the manner in which one housekeeper finally got rid of these pests : " My own experience with them began last year. We moved to our present abode in April, and it was not until every carpet had been put down and the house settled that I was aware that we had such unwelcome guests. I was not long in observing their habit of running into any crack and crevice that presented itself, and also running along the joints of the floors, and our warfare against them was directed toward these joints. In the closets we stopped up every nook on the walls ; every crevice under the baseboards, and filled up the joints of the floors ; then we laid down oil-cloth, and kept a plenti- ful supply of camphor in the closets. I am happy to say that we have had no trouble with them since so doing. "Fortunately, we had put paper under all the carpets, so we felt that they were in a measure, at least, protected, but I found them continually, just under the edges of the* carpet. As far as possible, we filled up the crevices under the baseboards and I used benzine plentifully all the sum- mer, saturating the borders of the carpets every two weeks and killing all I saw in the meantime. Last spring we varnished the cracks of the floors, and in some cases, where they were open, covered them with strips of thin muslin stuck down with the varnish ; we again put paper under the carpets, as we had found it such protection the previ- ous year. I have found the various insect powders of no use whatever when the insect is in the larval state: whether or not it has any effect on the beetle I cannot say ; but this I can state, — that our unceasing warfare has not been in vain, for I have, during the past summer, seen only single ones where last year I found scores." INSECTS INJURIOUS TO CLOTHES 209 Hydrocyanic acid gas is quite as effectual for the carpet beetle as it is for the bedbug and may be used in exactly the same manner as was described in the chapter on the latter insect. The fumes of sulfur are quite as effective if enough of the sulfur is burned at one time. Not less than two pounds to a thousand cubic feet should be used. The room should be tightly calked and closed as described in the chapter on the bedbugs. We would again call attention to the injury that may result from sulfur fumes to metals, wall paper, and gilt objects. As we have pointed out the larvae tend to congregate mostly about the edges of the carpets. It is said that a solution of sixty grains of corrosive sublimate dissolved in a pint of alcohol and applied to the edges and undersides of the carpets around the borders will poison the larvae when they begin to eat the fabric. The alcohol quickly evaporates and leaves the corrosive sublimate among the fibers of the carpet where it will remain a long time. Since this material is such a virulent poison, great care must be exercised in regard to children when playing about the room lest they get hold of some of the material and become poisoned. The larvse may be trapped by placing woolen cloths, especially red ones, in closets. Among these, the larvae will congregate and may be caught by shaking the cloths once a week over a piece of paper. Furs and woolens may be stored in boxes in the same manner as recommended for protection against clothes moths. The box arranged for the application of carbon bisulfide serves as well in protecting materials from the carpet beetle as it does from clothes moths. 210 HOUSEHOLD INSECTS THE BLACK CARPET BEETLE Attagenus piceus In the case of this insect (Fig. 61) we have a pest with a varied menu and consequently one that is apt to be found committing a different kind of injury in different surround- ings. For example, Hagen records it as a museum pest in the insect collection at Cambridge, Massachusetts, as early as 1878. The slender larva persists until it finds a crack or slit in the box of specimens and then enters to feed upon the dead bodies of the insects, thus causing much injury. Again, it has been caught doing damage in flour mills and is some- what of a feeder on cereal products. Moreover, it is a frequent pest in feathers and sometimes causes what is known as "felting" in pillows. The short branches of the feathers which are stripped off by the larvae in their feeding activities become firmly stuck into the cloth and form a close felting all over the inside of the ticking. Riley, in a case observed by him, says, "The felting was re- markably dense, evenly coating the whole surface of the ticking and greatly resembling in softness, smooth- ness, and color the fur of a mole." Finally, Lintner found the larvae of this beetle in company with the FIG. 61. — Black carpet beetle. (X 9.) INSECTS INJURIOUS TO CLOTHES 211 "buffalo moth" about the edges of carpets in a house at Schenectady, New York, in 1876. He, at first, supposed it was about the borders of the carpet in search of dead flies and the cast skins of the "buffalo moth," but, later, he found it a real enemy of the carpet itself. Since that time, this insect has become quite a noted carpet pest in this country. It has become more numerous in some houses than the "buffalo moth," and in the city of Washington, Howard says it has be- come very abundant and has taken the place of Anthrenus scrophularioe. It is widespread in Europe and Asia and has been in the United States for many years. It has been said that this beetle is not so fond of working in cracks in floors as the " buffalo moth," but many of the larvse of these beetles have been found in the floor cracks of a house in Ithaca, New York. F™- 62. — Larva of They apparently bred in the cracks beetle. a°(x 5°)"^ all the year round. The cast larval skins and living, mature larvae were found in January. Like the " buffalo moth," it is not the adult that commits the injury, but it is the larva that does the damage. The larva is long and slender and tapers toward the posterior end. It is reddish-brown in color, quite active, and clothed with hairs, while the posterior end of the body terminates in a pencil of long hairs. It is easily distinguishable from the "buffalo moth" and the illustrations should enable any one to tell the two apart (Fig. 62). 212 HOUSEHOLD INSECTS The adult is a small, blackish beetle only about one- sixteenth of an inch in length. It is about twice as long as wide and rather flattened (Fig. 61). It is very sober in coloring and can readily be distinguished from the much gayer colored "buffalo moth" beetle. The life history of this insect is not well known. Its eggs are white, of a broad, oval shape, and are probably deposited about the edges of the carpets or upon the woolens or other materials it may be feeding upon. Chittenden has met with the larvae in seeds and other vegetable matter and has shown that they will breed successfully from the egg in flour and meal. In his studies of the life his- tory of this pest he found that two years were re- quired for its development from egg to beetle. The pupal stage was shown to last from six to fifteen days. We have had the adults appearing in May in our breed- ing jars and in dwellings. The pupa? (Fig. 63) are clothed with a coat of whitish hairs among which debris becomes entangled, the whole resembling a very thin, delicate cocoon. On the dorsal side of each of six segments of the abdomen there is a brownish eye-like spot. The inner edges of the spots are fringed with minute teeth. When the pupa is stroked with a needle along the back, these spots contract and close up. The larvae of the black car- FIG. 63. — Pupa of the black carpet beetle, dorsal and ventral view. (X 9.) INSECTS INJURIOUS TO CLOTHES 213 pet beetle are certainly active throughout the winter in well-heated houses. Methods of control. — Since the habits of this pest are so similar to those of the "buffalo moth," the same reme- dies may be applied to it. REFERENCES TO ECONOMIC LITERATURE ON THE CARPET BEETLES 1878. - —The new carpet bug (Anthrenus scrophularice). Ent. Contributions, No. 4, pp. 15-23. 1878. HAGEN, H. — On the new carpet bug. Can. Ent., Vol. X, pp. 161-163. 1878. Attagenus megatoma as a museum pest. Proc. Bost. Soc. Nat. Hist., XX, pp. 56-61. 1879. LINTNER, J. A. — Attagenus megatoma feeding on carpets. Country Gentleman, xliv, p. 503. 1880. RILEY, C. V.— Trapping the carpet beetle. The Amer. Ent., Vol. Ill, No. 3, pp. 53-55. 1882. Attagenus megatoma causes felting. Amer. Nat., Vol. XVI, p. 1018. 1884. DIMMOCK. — Attagenus megatoma causing felting. Cassino's Nat. Hist., Vol. II, p. 378. 1885. LINTNER, J. A. — Attagenus megatoma. Second Rept., Ins. N.Y., pp. 46-48. 1889. RILEY, C. V. — Some insect pests of the household. Insect Life, Vol. 2, pp. 127-130. 1889. FERNALD, C. H. — Household Pests. Bull. 5, Mass. (Hatch) Expt. Stat. 1890. RILEY-HOWARD. — Feather felting by dermestids. Insect Life, Vol. 2, pp. 317-318. 1890. - — Another beetle destructive to carpets. Insect Life, Vol. 3, p. 65. 1892. Abundance of Attagenus piceus in Illinois. Insect Life, Vol. 4, p. 345. 1893. LINTNER, J. A. — Two carpet beetles. Ninth Rept., Ins. N.Y., pp. 299-306. 1896. The carpet beetle. Eleventh Rept., Ins. N.Y., pp. 172-174. 214 HOUSEHOLD INSECTS 1895. FLETCHER, JAMES. — Household pests. Kept, of the Ent. and Bot., Canada Dept. Agri., 1895, p. 165. 1896. HOWARD, L. O. — The principal household insects of the United States. Bull. 4, Bu. Ent. U. S. Dept. Agri., pp. 58-63. 1897. CHITTENDEN, F. H. — Some little-known insects affecting stored vegetable products. Bull. 8, n.s, Bu. Ent., U. S. Dept. Agri., pp. 15-19. 1902. WASHBURN, F. L. — Carpet beetles, etc. Bull. 77, Minn. State Expt. Stat., p. 56. 1904. SLINGERLAND, M. V. — The carpet beetle. Circ. 10, Cor- nell Reading-course for Farmers' Wives. 1905. FLETCHER, JAMES. — The buffalo carpet beetle. Can. Ent., Vol. 37, p. 333. 1906. WASHBURN, F. L. — Carpet beetles, "buffalo bug," "buffalo moth." Eleventh Kept, of the Minn. State Ent., p. 69. 1906. LOCHHEAD, WM. — Household insects. Can. Ent., Vol. 38, p. 67. 1908. HOWARD, L. O. — The carpet beetle or "Buffalo moth." Circ. 5, Bu. Ent., U. S. Dept. Agri. For further bibliography see Lintner, Ninth Report. FISH-MOTHS Lepisma saccharina In taking from a shelf a book that has remained undis- turbed for some time, we often catch a glimpse of a glis- tening or silver gray insect (Fig. 64) that glides quickly out of sight. In fact, this insect is an adept at dodging and when actually in contact with the fingers, the slick, shining body easily slips from the grasp. It is not a moth nor is it closely related to a moth nor does it remotely resemble a moth in general appearance or habits. Its body is clothed with shining scales like that of a fish and some person who had caught it injuring clothes in a manner similar to the larva of a clothes moth combined the character with the INSECTS INJURIOUS TO CLOTHES 215 habit and thereupon dubbed it a fish-moth. It is quite common to call any insect found injuring household effects a moth, even though it is far removed from the group of insects containing the moths and butterflies. The glis- tening body of the fish-moth, its quick, gliding movements, and its ability to appear and as quickly and mysteriously disappear have resulted in its having received a number of names in different localities. It is variously known as the silver-fish, silver-witch, sugar- louse, sugar-fish, wood-fish, and bristle-tail. Food and injuries of the fish-moth. — It is still a question whether this insect lives mostly upon vegetable or animal products, or, at a pinch, upon both. It is commonly said that the fish-moth lives upon vegetable matter, mainly upon starch and sugar. In proof of this, the injuries to laundered clothes, bindings of books, wall paper, and similar materials are cited. It has been said that the insect attacks these objects to get at the starch or paste in them. Not long ago we received a letter from a care- ful housekeeper, accompanied by several specimens of this insect, saying that they were seriously injuring the curtains hung at the windows of a room very little used. These curtains had supposedly been starched, although the letter was not specific on this point. At any rate, something in the curtains other than the fiber, probably the starchy material, had proved attractive as a source of food to the fish-moths and the in- juries followed. In this connection, M. de Rossi says that muslin curtains are sometimes perforated by fish-moths. 216 HOUSEHOLD INSECTS On the other hand, Garman says he has become con- vinced that these insects feed upon animal matter and cites an instance of some velox photographic prints from which the film had been removed by them in patches while the starch used in mounting the prints had remained un- touched. In attempting to catch the depredators, baits of starch and sugar, both moist and dry, were set for them, but not the slightest attention was given to these food products by the insects. On the other hand, bits of white glue alone and dusted with Paris green, when placed about, were readily devoured by the pests. Moreover, the dead bodies of fish-moths were eagerly eaten by their living comrades. Taking these observations, as a whole, Garman is inclined to believe that these insects have a fondness for animal food and that they attack book bind- ings, gummed labels, and so on, mainly, for the animal matter contained in the glue on them. It must be stated, however, that the great majority of writers on these insects hold that they eat vegetable matter and they certainly do, at times. Hagen brings together considerable evidence to prove that Lepisma shows a decided taste for starchy matter. He says, "If we tabulate all the facts, we find directly that all damage, except those to paper and its combinations, have been inflicted on silks, clothing, and muslin curtains which were invariably starched or finished with some stiffening size, making them more easily eaten or eroded. Secondly, the backs of books may have been more or less seriously injured. But just -here paste had been used in quantity." Book bindings are often badly scarred and scraped by these insects in their efforts to obtain the included glue or INSECTS INJURIOUS TO CLOTHES 217 paste. Even the gold lettering on volumes has been eaten to get at the sizing beneath, and gummed labels used in museums and on books in libraries are often destroyed by them. Heavily glazed paper offers an attractive source of food to these insects and books made of such paper often have their leaves badly scraped and scarred. Wall paper is sometimes attacked by fish-moths and the starch so eaten up over a large area that the paper breaks loose from the walls. Starched collars, cuffs, and shirts, espe- cially when laid away for a long time, are apt to suffer injury. Silk garments and silken tapestries have been injured occasionally, due, probably, to the material used in them for stiffening. In the Museum of Comparative Zoology at Cambridge, 700 labels on a collection of Paleontological specimens were all injured by fish-moths. Many of these were eaten enough to obliterate the writing and riddle the paper with holes. All of them had to be rewritten. The injury in this particular case, however, was ascribed to another species (Lepisma domestica). In such cases the loss is considerable and might be very serious if the labels on rare specimens became so defaced that the records could not be made out. Undoubtedly these insects do eat paper, when driven to it, for when S. Henshaw inclosed some of the fish-moths in a jar with only paper they readily ate holes in it. It is recorded that some books kept in a safe were attacked by a species of Lepisma. Occasionally vegetable drugs or similar materials are damaged by fish-moths. Description of the insect. — The fish-moth is a member of the lowest and simplest group pf insects. It has no wings and its body is about one-third of an inch in length, tapers gradually from the head to the posterior extremity, 218 HOUSEHOLD INSECTS and is covered with minute silvery scales. On account of the covering of scales, it is almost impossible to catch an individual without crushing or greatly damaging it. As one correspondent said, "I have never been able to get one, as they are extremely quick in motion and when killed are crushed." Like all other insects it has six legs which, although not abnormally long, yet are powerful and enable it to run very swiftly for so small an animal. The two "feelers," or antenna?, are very long, slender, and conspicuous. Moreover, at the posterior end of the body are three, long, slender, bristle-shaped projections, the middle one extending straight backward and the other two extending to the right and left at considerable angles. It has biting mouth-parts consisting of two pairs of jaws. One of the earliest notices of this insect occurs in a book called " Micrographia, " written by R. Hooke, and pub- lished in London by the Royal Society in 1665. The following quaint description of the fish-moth is given : " It is a small white Silver-shining Worm or Moth, which I found much conversant among Books and Papers, and is suppos'd to be that which corrodes and eats holes through leaves and covers; it appears to the naked eye a small glittering Pearl-coloured Moth, which, upon the removing of Books and Papers in the Summer, is often observ'd very nimbly to scud, and pack away to some lurking cranney, where it may the better protect itself from any appearing dangers. Its head appears big and blunt and its body tapers from it towards the tail smaller and smaller, being shap'd almost like a carrot." Although we think of this as a rather crude description, yet it is sufficiently clear to enable us to recognize the insect under discussion and, INSECTS INJURIOUS TO CLOTHES 219 at the same time, shows what a long standing pest it is. Nothing is known of its life history. There is another species of fish-moth present in this country, but not so well known to housekeepers. It was described by Packard in 1873 in a paper on the Thysanura of Essex County, Massachusetts. He called it Lepisma domes- tica and said it was common in houses of Salem about hearths and fireplaces, in warm and dry / situations, eating sugar, and other foods. He described it as having a broad body, pearly white, with a dense coat of scales and mottled with dark spots (Fig. 65). The same species, evidently, exists in Eng- land and it has since been named Thermobia funiorum. Both of these names refer to its heat- loving propensities. It seems to be abundant in bakeshops about the ovens where the heat ,, , , FIG. 65. — The domestic fish- would appear too great for any moth, (x i£). insect to withstand. It also occurs about fireplaces and ranges in dwellings and runs over hot bricks and metal with apparent impunity. In England, on account of . its habits, it is called the " firebrat." A Dutch entomologist, Oudemans, who has given con- siderable attention to the group of insects to which the fish-moths belong, says that he finds this heat-loving species in all bakeshops in Amsterdam that he has investi- gated and adds, that it is well known to the bakers. 220 HOUSEHOLD INSECTS Marlatt says that it is very abundant in Washington City. Dean s*ays that this species has often been observed in mills in Kansas. This species resembles the more common fish-moth in general appearance. It is usually larger, the body being about one-half inch in length. As pointed out before, the back of the insect is mottled with dark spots, by which it may be readily told from the first species discussed. Then, again, its habits are quite distinct and characteristic. Methods of control. — Usually books stored in moist basements or other damp rooms are most injured. This, of course, suggests airy, dry rooms for the storage of books or valuable papers if one wishes to preserve them free from injury by the fish-moth. Another common method of preventing injury to books and papers by these insects is by the frequent use of buhach. The fresh buhach should be sprinkled freely on the shelves and about on the books themselves. More- over, this treatment should be given frequently where these pests are abundant and persistent because the pow- der so soon loses its strength. In houses badly infested, starched clothes, stiffened silks, and similar fabrics should not be allowed to rest too long packed away in drawers or loose in chests or boxes. It is customary among librarians to poison sweetened paste with white arsenic, spread the mixture on pieces of cardboard, and slip them about on shelves among the in- fested books as baits for the fish-moths. In the light of Garman's experiments, it would seem that a like method of procedure in which glue is substituted for the starchy matter might succeed better in killing the pests. These INSECTS INJURIOUS TO CLOTHES 221 pieces of cardboard might be used to place about among garments or other stored fabrics if injury by the fish-moths is anticipated. REFERENCES TO ECONOMIC LITERATURE ON FISH-MOTHS 1886. HAGEN, H. A. — On a new library pest. Cand. Ent, Vol. XVIII, pp. 221-230. 1886. JACKSON, R. T. — A new museum pest. Science, Vol. VII, May 28, p. 481. 1890. RILEY, C. V. — The skein centipede and silver fish. Insect Life, Vol. 2, p. 315. 1893. GARMAN, SAMUEL. — The ravages of bookworms. Science, Vol. XXI, March 24, p. 158. 1896. BUTLER, E. A. — Household insects, pp. 314-324. 1898. FELT, E. P. — Lepisma domestica Pack. 14th Rept. of the N. Y. State Ent., pp. 216, 218. 1901. HOWARD, L. O. — Family Lepismatidse. Insect Book, p. 382. 1902. MARLATT, C. L. — The silver fish. Circ. 49, s.s., Bu. Ent., U. S. Dept. Agri. 1903. HOULBERT, G. — Les insectes ennemis des livres, p. 155. 1906. GARMAN, H. — Does the silver-fish (Lepisma saccharina) feed on starch and sugar ? Bull. 60, Bu. Ent., U. S. Dept. Agri., p. 174. 1906. WASHBURN, F. L. — Silver-fish, "fish-moth." Eleventh Ann. Rept. of the State Ent. of Minn., p. 71. 1907. SMITH, JOHN B. — Some household insects. Bull. 203, N. J. Expt. Stat, p. 42. 1913. DEAN, GEO. A. — Mill and stored-grain insects. Bull. 189, Kan. State Agri. Expt. Stat. p. 235. CRICKETS Gryllus domesticus et al. The following interesting letters give the different phases of annoyance from crickets frequenting dwelling- 222 HOUSEHOLD INSECTS houses. The first correspondent writes as follows : " I am writing to ask how to kill crickets. The house is built almost level with the ground and crickets have been able to get in the French windows, go up stairs on the rough plaster walls, and get into all the cracks in the woodwork. During August and September of last year I killed thirty or forty crickets a day as they bred in the walls and I feared they would eat clothing if left to themselves. Also they kept us1 awake at night." The second correspondent gives another and more serious phase of annoyance from crickets. She says : " We will be very glad to have you tell us how we may rid our house of the common black crickets. They get into the closets in some unaccountable way and destroy the cloth- ing, both linen and woolen. After destroying every one of them in the morning we go into the closets in the after- noon to find as many more as formerly. They seem to eat holes very similar to the moth." To many householders, the presence of a " cricket on the hearth " is a source of pleasure, and in Spain it is said that crickets are sometimes kept in cages much as we keep canary birds. One might be quite ready to agree with the first correspondent, however, that a multitude of crickets with their peculiar chirpings could become anything but a delight, especially at night. Again, the common black cricket, as the second correspondent writes, often causes serious injury to clothing. Lintner records an interesting instance of this in the case of a common black cricket. He says, "Wm. B. Marshall of the New York State Museum at Albany, reports during a sojourn at Cape May, New Jersey, in the month of July last, that a suit of clothes belonging to a friend which had just been received from the INSECTS INJURIOUS TO CLOTHES 223 tailor and was hanging over a chair was completely ruined in a single night by crickets that had entered through open windows and eaten large holes in the garments." Lintner identified the crickets as Gryllus luctuosus, a common black species. Crickets hibernate as adults through the winter and, of course, seek warm protected places in which to hide. Very often in the fall, as the nights grow cold, they enter dwelling-houses, especially those that may be temporarily unoccupied. Here they often attack woolen clothing hanging in closets and cause serious injury by eating the garments full of holes. When the occupants return and start the fires they often find the house full of these noisy and rather unwelcome guests. The crickets with which American residents are probably most familiar are individuals of the common blackish or brownish-black species present everywhere. These are not true house crickets, for they live in the fields and do not breed in houses so far as is known. The domestic cricket is a European insect, but it was probably intro- duced into this country very early in its history. It is evidently quite widely distributed in America, although it cannot be said to be common in the United States. It is much more common in Canada. The house cricket (Gryllus domesticus) is of a pale brown color throughout (Fig. 66). It frequents more commonly the ground floors of houses and ensconces itself about the chimney, where there is sufficient warmth. Because of the warmth and food in bakeries it is often found in these shops. Like other crickets, it is mainly nocturnal in habits, waiting until the dusk of evening before beginning its activities in hunting food and chirping its love song. 224 HOUSEHOLD INSECTS Very little seems to be known regarding its actual life history, but as all sizes are found in houses ft is inferred that the eggs are laid in dwellings and that the whole life history may be passed in the house. In summer, in Europe at least, it is often found out-of-doors about hedges and in gardens, but it returns to the houses for warmth in the fall. There are certain supersti- tions connected with crickets that cause them to become objects of considerable interest and to be looked upon by some as harbingers of good or evil. To many, their chirping is an omen of good cheer, while in others it induces sadness and melancholy. To many people the out-door crickets, in the autumn, seem to be voicing the dying of the year. There is also a curious superstition that if one kills a cricket, its relatives will hunt out the garments of the enemy and riddle them with holes. Only the male crickets are musical, and it is interesting to watch them produce their song. If one of the males of the common field crickets is brought into the- house in the fall and placed in a glass jar with a few pieces of bread crumbs for food, it will soon come to feel at home and will sing its song without fear or trepidation. The chirping noise of the cricket is produced by the upper pair of wings that FIG INSECTS INJURIOUS TO CLOTHES 225 bear special structures for the purpose and are put into rapid motion, as we shall see. The large vein that runs diagonally across each of the upper wings near their bases is crossed with many file-like ridges. Also, not far from the tip of each wing along the inner margin is a hardened membranous portion which may be called the scraper or drum. Thus each of the upper wings is furnished with a file and a scraper. When the cricket desires to make his chirping song, he elevates these wings at an angle of about forty-five degrees and holds them so that the scraper of one rests upon the file of the other. He then moves the wings very fast from side to side, rasping the scraper of each wing with the file of the other. This movement throws the wings into vibration and produces the chirping sound. Since the cricket can make sounds, we would have a right to infer that it is endowed with the sense of hearing. Cu- riously enough, there is an oval transparent disk on each of the fore legs that undoubtedly serves as an ear or organ for perceiving sound. Methods of control. — Crickets are very fond of certain liquids like beer and sweetened vinegar. It is said that their extreme fondness for these liquids literally drives them to drink ; for if deep glass vessels are half filled with a favorite liquid and placed where the insects can easily get into them, they can be trapped and drowned in great numbers. The author has never had an opportunity to try this method of catching crickets, but it is given on excellent authority. They may also be killed by poisoning pieces of fresh carrots, parsnips, or potatoes with arsenic and placing them about where the crickets will easily find them. Of course great pains must be taken not to put the bait where children can get hold of it. 226 HOUSEHOLD INSECTS REFERENCES TO ECONOMIC LITERATURE ON THE CRICKETS 1893. LINTNER, J. A. — The common black cricket. Eighth Kept. N. Y. Ins., p. 179. 1895. SHARP, DAVID. — Cambridge natural history, Vol. 5, p. 330. 1895. COMSTOCK, J. H. — Manual for the study of insects, p. 115. 1896. MARLATT, C. L. — The principal household insects of the United States. Bull. 4, n.s., Bu. Ent., U. S. Dept. Agri., p. 52. 1896. BUTLER, E. A. — Our household insects, p. 147. 1905. KELLOGG, V. L. — American insects, p. 157. CHAPTER X INSECTS INJURIOUS TO CEREALS AND PRESERVED FRUITS CEREALS, like wheat, corn, oats, and rice and their products together with preserved fruits, both in the dried, and liquid form, are subject to the attacks of several species of insects. The principal offenders are the larvae of beetles and moths, but the maggots of certain flies are often injurious to preserved fruits. Most of these pests are inhabitants, primarily, of granaries, storehouses, and mills from which they find their way into the house- hold by being brought in with food-stuffs. THE- DARKER MEAL-WORM Tenebrio obscurus ' There are two species of beetle larvae, called meal- worms, that work in meal, flour, and other cereals. They are very much alike in general appearance. The one under consideration has been called by many writers the American meal-worm. There is no valid reason for calling it an American insect because it is undoubtedly of Euro- pean origin. We are, therefore, calling it the darker meal- worm, thus varying slightly from Chittenden, who has already written of it as the dark meal-worm. Distribution and food. — The darker meal-worm is certainly widely distributed in this country and in Europe. 227 228 HOUSEHOLD INSECTS The larvse and pupae of both species of meal-worms are used for bird food and are grown in quantity by bird supply houses. The beetles will increase readily and rapidly when placed with a supply of bran or meal. The larvse are found in granaries, storehouses, bake- shops, barns, dwrelling-houses, and grocery stores. The author has found them in numbers in oat bins. The larva? eat meal, flour, bread, cake, and cereals. Since they so frequently occur in mills, they are un- doubtedly ground up with meal and we probably eat the remains greatly diluted. However, none of us seem to be any worse for it and we trust that no one will be deterred from eating and enjoying all forms of corn-meal products. Appearance of the beetle and "worms." — The beetle is dull black, often reddish-black and about one-half inch long. Running lengthwise of the wing-covers on the back are sixteen deep furrows plainly visible to the eye. The antennas are conspicuous, although not long, and look like a string of black beads (Plate III) . In this species the third segment of each antenna is noticeably longer than the cor- responding segment in the beetle of the yellow meal-worm. The larva? of meal-worms are long, slender, and cylin- drical. The skin is evidently heavily chitinized and therefore rather hard. The meal-worms are about one inch long, yellow in color, but shading off into yellowish- brown at either end and at the joining of the segments. The posterior segment of the abdomen ends in two minute dark-colored spines. They are furnished with three pairs of very serviceable legs, which enable them to travel quite fast unless they are on a polished surface. When the larva attains its growth it changes to the pupa. The pupa is whitish in color and about five-eighths of an PLATE III ^p :-•//' i^^yS/-' •>•*;* -Ci>'. ' Beetle of darker meal-worm (X 3) and pupa (X 2^) ; pupae and larva of meal-worm (XI); yeast cake injured by drug-store beetle. INSECTS INJURIOUS TO CEREALS 229 inch long. The abdominal segments have curious fringed expansions on each edge and the last segment of the abdomen terminates in two spines, sharp and dark-colored at the tips (Plate III). Methods of control. — The darker meal-worm may be controlled by the same methods as the yellow meal-worm. THE YELLOW MEAL-WORM Tenebrio molitor The larva of this beetle is much like that of the darker one just described in size, shape, and general appearance except that it is lighter in color. The larva is about one inch in length, cylindrical in shape with hardened shining skin, much resembling a wireworm in appearance. It is yellowish in color, shading to a darker tinge at each end and at the joining of the segments. The last segment of the larva terminates in two small spines, although West- wood and Packard describe it as having but one spine. The beetle closely resembles Tenebrio obscurus in shape and general appearance. The color, however, of this beetle is shining black, while Tenebrio obscurus is of a dead opaque black. The white eggs of the beetle are deposited among the meal or cereal upon which the larvae are expected to feed. The eggs are covered with a sticky material and the par- ticles of meal adhere to them. Sometimes the eggs are laid singly and sometimes in bunches. In ten days to two weeks or more, depending upon the temperature, the eggs hatch and the tiny white meal-worms appear. They begin to feed at once and soon take on their yellowish, glossy appearance. The larvae take a considerable period 230 HOUSEHOLD INSECTS for their growth, three months or longer. The pupal stage lasts about two weeks. Under normal conditions the beetles appear in the spring of the year, but where the meal- worms are being reared in the house the adults are appear- ing at any and all times. Normally, there seems to be but one generation a year. The yellow meal-worm is a common species in the Old World, but it has been widely distributed over the earth through the activities of commerce. It was purposely introduced into Chili to furnish food for domestic birds. The larvae of this beetle are found in corn-meal and flour the world over, where they can be made to breed almost indefinitely. There are on record several instances in which these larvae have evidently been swallowed by people while eating corn-meal mush, or other materials in which the larvae live. It is hard to see how the larvae withstand the heat generated in cooking the food. In addition to this, the person eating the food must necessa- rily swallow it with very little mastication in order for the larvae to enter the stomach whole, as without doubt they sometimes have. An interesting case is related in Insect Life in which two of these larvae were ejected from the stomach of a woman. Evidently the movements of the larvae in the stomach had caused nausea and finally vomiting. An interesting and rather humorous account of the occurrence of this beetle in a pincushion on the dresser of a hotel bedroom has come down to us also through Insect Life. A guest, who had occupied the bedroom, com- plained in the morning to his host that the room was haunted. The host, of course, pooh-poohed the idea, but the occupant persisted in his story and related how the INSECTS INJURIOUS TO CEREALS 231 bogies had plagued him. He said they were around the dresser and had kept him awake most of the night by the incessant scratching sounds produced somewhere about the furniture. Investigation showed that the scratching noises were present and were evidently issuing from a large pincushion lying on the dresser. When opened and the filling, composed of coarse shorts used as a food for horses, had been shaken out, several large black beetles of this species appeared among the grain. Evidently some of the larvse or beetles had been inclosed with the shorts and had been breeding in the meantime within the cushion. The grain had served as food for them. Methods of control. — The most practicable remedy is fumigation with carbon bisulfide, especially in granaries and meal bins. If meal or flour becomes infested in the house, it can be placed in a tight box or barrel and fumi- gated. After fumigation, the meal or flour should be carefully sifted in order to remove the dead bodie's of the insects. As in other cases already recommended, the carbon bisulfide should be used at the rate of two pounds to 1000 cubic feet of space. Half a teacupful should be ample for 50 pounds of meal or flour if the fumigation is done in a small tight box or barrel. It will be necessary to thoroughly clean the box or bin before putting in a new supply of flour. REFERENCES TO LITERATURE ON THE MEAL-WORMS Tenebrio molitor 1889. RILEY, C. V., and HOWARD, L. O. — Larvae of Tenebrio molitor in a woman's stomach. Insect Life, Vol. 1, pp. 379-380. 1889. Beetles in a pincushion. Insect Life, Vol. 2, p. 148. 232 HOUSEHOLD INSECTS 1893. LINTNEK, J. A. — Tenebrio molitor. Eighth Kept. Ins. of N.Y., pp. 176-177. 1896. CHITTENDEN, F. H. — The principal household insects of the United States. Bull. 4, Bu. Ent., U. S. Dept. Agri., pp. 116-117. Tenebrio obscurus 1893. LINTNEE, J. A. — The American meal-worm. Ninth Rept. Ins. N.Y., pp. 307-308. 1896. CHITTENDEN, F. H. — The principal household insects of the United States. Bull. 4, Bu. Ent., U. S. Dept. Agri., pp. 117-118. See Lintner's Ninth Rept. for further bibliography. THE CADELLE Tenebroides mauritanicus The Cadelle is more particularly a stored-grain insect than a household pest. It and its larvae are frequent occupants of granaries, mills, and storehouses and from these often find their way into households in cereals and other food products. Many years ago the French applied the name "Cadelle" to this beetle and it has been known under this name ever since. The Germans often term it the bread beetle. It is of world-wide distribution although r IG. u/. — inc L^aaetic. 0 (x 4.) Chittenden remarks that ' there is every reason to believe that this insect is of American nativity." The adult insect is a dark, shining-brown beetle about f of an inch in length (Fig. 67). It is therefore somewhat smaller than the meal-worm beetles, but much larger than INSECTS INJURIOUS TO CEREALS 233 the confused flour beetle. The head and thorax are finely punctate and the wing covers are longitudinally ridged. The prothorax and head are distinctly separated from the rest of the body, as shown in Fig. 67. The larva, shown in Fig. 68, is whitish or flesh-colored and about three- fourths of an inch long when full grown. The head, prothorax, and tip of the abdomen are dark reddish-brown. The last two segments of the thorax are also usually brownish. The end of the abdomen bears two dark corneous hooks. Altogether the larva is quite formidable in appearance, although it is perfectly harmless. The pupa is white and, as we describe later, is formed in a cell burrowed out in soft wood, at least when the wood is available. There has been considerable differ- ence of opinion as to whether this insect lived upon plant food or upon other insects and small animals. There is no doubt about its being herbivorous, for it has been proven again and again that it feeds upon various grains. Chittenden says he has proven through experiments that it is also predaceous. Some years ago several specimens of the adult beetles and larvae were sent to this department by a correspondent in Ohio. They were infesting wheat in a granary and had injured the grain badly. Curiously enough, when the larvae became nearly full-grown they burrowed into the pine boards forming the bins and changed to pupae within FIG. 68. — Larva of the Cadelle. (X 3.) 234 HOUSEHOLD INSECTS the burrows. We show in Fig. 69 a section of the side of a bin showing the burrows made by the larvae. Slingerland made observations on the life history and habits of the beetles for a period of nearly a year in which he kept them in the insectary. He placed the beetles in tumblers containing wheat. Here the beetles freely laid their eggs, which hatched and the larvae came to maturity, using the wheat grains as food. We have also found them in oatmeal and kept them under observa- tion for a long in- terval in this cereal. FIG. 69. — Section of bin showing holes in the n^ • qrrml] wood made by the larva of the Cadelle. * ne C^ 1S a small> white object, much longer than wide and slightly curved. It would take nearly 20 of them, placed end to end, to reach one inch (1.3 mm. long and .3 mm. wide). Eggs laid about August 5th hatched August loth, thus indicating an incubation period of about ten days. The newly hatched larvae are very small and resemble the full- grown ones in color and general appearance. The larvae that hatched from the eggs in August grew slowly and lived in the warm insectary among the wheat grains until the following April and May. In the latter part of April one larva was found in a burrow in a pine stick that had been placed in the tumbler. Later it pupated in its burrow. About the middle of May another larva was found in its burrow in a pine stick. A month later this larva had changed to a pupa and on July 10th one of these pupae had changed to an adult beetle, while the other had dried up and died. Thus it evidently takes about one year for the insect to pass through its life cycle. INSECTS INJURIOUS TO CEREALS 235 The beetles, themselves, are apparently long-lived insects, for Slingerland kept one of them alive and active for nearly a year in the tumbler. Another observer kept one alive for twenty-one months. The larvae of the Cadelle have been found in all sorts of unexpected places and among various kinds of food-stuffs. An instance is given in Insect Life in which a correspondent sent in a larva which had been found in a bottle of milk. Very likely, in this instance, the insect had crawled into the empty bottle from near-by grain and had remained there unnoticed when the bottle was filled. A far more interesting occurrence of the beetles is that related by Webster, in which he found two beetles that had tunneled through a cork and burrowed into a quantity of white hellebore. The beetles when found were dead, but they had channeled the material in all directions, showing that they had lived in the powder some time. The material, however, was old and had lost much of its strength, al- though later, when sifted upon gooseberry bushes, was found strong enough to kill the imported currant- worms. The larvae of the Cadelle have also been found in one or two instances in sugar. Their presence there was probably accidental. The beetles and the larva? were found by Johnson boring through the parchment paper of jars containing jams and jellies imported from Liverpool, England. After the insects had tunneled through the paper they fed upon the surface of the preserves. Miss Ormerod found the larvae feeding upon the larvae of the rust-red flour-beetles. The injury done to cereals by the Cadelle is somewhat counterbalanced by its predaceous habits. 236 HOUSEHOLD INSECTS Methods of control. — The Cadelle can be controlled by taking the same measures recommended for the meal- worms. REFERENCES TO ECONOMIC LITERATURE ON THE CADELLE 1839. WESTWOOD, J. O. —An. Introd. to the Mod. Class, of insects, p. 147. (Gives other references.) 1883. CURTIS, JOHN. — Farm insects, pp. 332-334 (2d ed.). 1888. RILEY and HOWARD. — Insect life, Vol. 1, pp. 112, 314, 360. 1895. CHITTENDEN, F. H. — The more important insects injurious to stored grains. U. S. Dept. Agri. Yearbook, 1894, pp. 277- 294. 1896. DAVIS, G. C. — Some injurious insects. Bull. 132, Mich. Expt. Stat., p. 21. 1899. JOHNSON, W. G. — The bolting cloth beetle. Tenebroides mauritamcus. Bull. 20, n.s., Bu. Ent., U. S. Dept. Agri., p. 67. 1900. ORMEROD, ELEANOR. — "Cadelle," bread beetle. 23 Rept. Inj. Ins., pp. 56-59. 1901. DE CHAMPVILLE, G. F. — Les ennemis du ble, pp. 61-63. 1909. SMITH, R. I. — The Cadelle. Bull. 203, N. C. Expt. Stat., pp. 11-12. See also Reports of 111. State Ents., IV, V, VI, XVI. THE SAW-TOOTHED GRAIN-BEETLE Silwnus surinamensis Among the insects which are injurious to stored grains there is a small, narrow, chocolate-brown or reddish beetle. It is scarcely one-tenth of an inch long, but makes up in numbers for its small size (Fig. 70). It is one of the most abundant beetles in all kinds of stored grains, especially in the Southern states . Moreover, in the Southern states it undoubtedly causes more loss in many instances, than any INSECTS INJURIOUS TO CEREALS 237 other of the stored grain insects. This insect is commonly known among the farmers as the " grain- weevil " or the "saw-tooth weevil." The beetle, itself, is a minute, flattened, reddish-brown beetle about one-tenth of an inch long. The thorax is the distinguishing feature of this insect. It is long and narrow and bears on each lateral margin a number, usually 6, of conspicuous tooth-like projec- tions. It is this characteristic that gives the beetle the name of "saw- tooth weevil." There are three strong ridges on top of the thorax with two wide sunken areas, one each side of the cen- tral ridge. The wing covers are longi- tudinally ridged with the areas be- FIG. 70. — The saw- tween finely punc- £»*£* ^-in-beetle. tate. The head is also densely covered with punctures. The larva (Fig. 71) is somewhat , flattened and has a transverse rec- tiu. 71. — Larva of saw-toothed grain- tangular chitimzed area on the dorsal beetle, enlarged. side Qf each body segment. On the thoracic and anterior abdominal seg- ments these rectangular areas may be divided in two by a whitish line through the middle. The larva, when living in granular material, like meal, usually builds a thin case out of the particles and the whitish pupa may 238 HOUSEHOLD INSECTS be found within. When the insect is living in substances like fine flour it does not build a case. The life history of this pest is not well known. It would seem that there may be several generations during a season, probably six or seven in warmer latitudes. During the summer months the life cycle occupies about twenty-four days, while in spring and fall during cooler temperatures a much longer time is required. The species apparently winters over in the adult condition. The saw-toothed grain-beetle is fond of meal, flour, and grain of all kinds. It is nearly always present in granaries and has been reported in starch, tobacco, and dried meats, although Chittenden says, "it is doubtful if the insect will breed in such substances." It is often present in dried fruits. Our records show that the beetles get into macaroni, cornstarch, ginger, and mustard, and that they attack dried peaches. They are often brought into the house in the materials purchased at the store. Moreover, the beetles have the habit of gnawing holes through paper bags, thus finding their way into stores of cereals supposedly well protected from invasion by insects. Taschenberg, in discussing this beetle under the name of Silvanus frumentarius, mentions an instance where the adults invaded dwelling rooms adjacent to a brewery in which grains were stored. The invading beetles developed the curious habit of creeping into the beds and nipping the sleepers. Evidently this grain beetle is widely distributed over this country and over the world. Taschenberg says that through commerce this species has spread over the whole earth. INSECTS INJURIOUS TO CEREALS 239 Methods of control. — The insect is amenable to the same methods of control described for the control of the flour-beetles, meal moth, and others of similar habits. As in the case of the other species, so with the saw-tooth grain-beetle, the attempts at eradication must be thorough and persistent. REFERENCES TO ECONOMIC LITERATURE ON THE SAW-TOOTH GRAIN- BEETLE 1879. TASCHENBERG, E. L. — The small grain beetles. Praktische Insekten-Kunde, II, pp. 19-20. 1893. BECKWITH, M. H. — Insects injurious to stored grains. 6th Ann. Kept. Del. Expt. Stat., pp. 154-155. 1896. CHITTENDEN, F. H. — The principal household insects of the U. S. Bull. 4, n.s., Bu. Ent., U. S. Dept. Agri., pp. 121-122. 1912. GIRAULT, A. A. — Insects injurious to stored grains and their ground products. Bull. 156, 111. Expt. Stat., pp. 79-80. THE ANGOUMOIS GRAIN MOTH Sitotroga cerealella The Angoumois grain moth (Fig. 72) is a European insect first reported as destructive at Lu9on, France, in the prov- ince of La Vendee in 1736. Shortly afterwards it was found destroying grain in the adjacent province of Angoumois, from which it received the name that has always clung to it. Early in the history of the American Colonies it Was FlG. 72._The Angoumois grain introduced somehow into moth, (x 3.) 240 HOUSEHOLD INSECTS North Carolina and Virginia. From thence it has spread over the Southern states and as far north as Massachu- setts, New York, and Michigan. It is more destructive in the South than elsewhere because of the warmer cli- mate, and it is primarily a pest of stored grains rather than of household products, although it is often found in popcorn (Fig. 73), rice, and other cereals. Life history and habits. — It is ex- ceedingly destructive to stored grains, especially in the South. It has been known to reduce the weight of grain 50 per cent in a few months. It in- creases very rapidly and because of the FIG 73 — Ear of secmded habits of the larva is difficult popcorn infested to control in any way except by heat with larvae of the d fumigation. , Ihe moth is light grayish-brown or straw-colored with its wings lightly mottled and lined with black, especially near the tips. The wings are long and narrow and the hind pair is fringed with long, delicate hairs along the posterior margins. The moths resemble clothes moths in general appearance and habits of flying, but they are somewhat larger, for their wings expand a little more than one-half an inch. Ihe moths deposit their white eggs moth, enlarged. Angoumois gram moth. INSECTS INJURIOUS TO CEREALS 241 (Fig. 74) on the kernels of corn or other grain. The eggs, which are elongated and regularly sculptured with FIG. 75. — Larva of Angoumois grain moth, enlarged. rectangular areas, soon turn to a pale reddish color. They hatch in five or six days and the tiny white larva (Fig. 75) burrows into the grain of corn, or wheat and lives on the substance in the interior. Like the grain-weevils, there may be two or more individuals in a grain of corn, but only one in a grain of wheat. In three weeks or more the larva be- comes full-grown, gnaws a circular opening nearly through the skin of the kernel for the escape of the moth, and spins a cocoon about itself inside the grain, where it pupates (Fig. 76). The moth emerges a few days later. In the field there are at least four broods in a season in the Southern states, and in grain stored in a warm room the insects breed throughout the FlQ- 76.— Pupa of the . Angoumois gram year. They pass the winter out-of- moth, enlarged, doors as larvae in the kernels of grain. The moth infests barley, corn, wheat, and other cereals. It is found in houses in popcorn, rice, and occasionally in other cereals. 242 HOUSEHOLD INSECTS Methods of control. — The same methods of control that were outlined for the grain-weevils will also hold the Angoumois grain moth in check. REFERENCES TO ECONOMIC LITERATURE ON THE ANGOUMOIS GRAIN MOTH 1862. HARRIS, T. W. — The Angoumois grain-moth. Insects Injurious to Vegetation (Flint edition), pp. 499-510. 1883. WEBSTER, F. M. — The Angoumois grain moth. 12th Kept. State Ent. of 111., pp. 144-154. 1897. CHITTENDEN, F. H. — The Angoumois grain moth. Farmers' Bull. 45, U. S. Dept. Agri., pp. 6-7. 1903. PETTIT, R. H. — The Angoumois grain moth. Special Bull. 17, Mich. Expt. Stat., pp. 22-24. 1912. GIRAULT, A. A. — The Angoumois grain moth. Bull. 156, 111. Expt. Stat., pp. 69-72. THE MEDITERRANEAN FLOTJR MOTH Ephestia kiihniella Some thirty-seven years ago this insect was discovered in a flour mill in Germany. Up to that time it had been comparatively unknown. In 1889 it appeared in destruc- tive numbers in Canada and three years later was found in mills in California. In 1895 it was reported present in flour mills in New York and Pennsylvania and during subsequent years it has spread over a large part of the United States and has become one of the most serious pests found in flour mills and buildings where cereals are stored. Naturally it has found its way into the kitchens, pan- tries, storerooms, and granaries of private households. The insect has been brought to these homes in sacks of INSECTS INJURIOUS TO CEREALS 243 flour, feed, and packages of cereals. Not long ago we received a complaint from a housekeeper in Ithaca, that a sack of bran in her storage bin was infested with many white "worms." A sample of the bran was obtained and the adults reared from the larvae. They proved to be the Mediterranean flour moth. Another instance of the same kind occurred in the house of an entomological colleague. In this case, the flour bin became badly infested with the larvae and moths. They entered the cracks and crevices of the bin, webbing together the waste flour and dust. The whole bin had to be very carefully gone over with a stiff brush and the larvae dis- lodged, swept up, and destroyed. This moth will probably continue to increase as a house- hold pest because it is now widely distributed among the larger flour mills of the country. It is bound to be brought into the homes of consumers in sacks of flour, feed, and cereals. The eggs, which are very small (Plate IV), are often deposited on sacks containing flour and other products of the mill, in which situations they are easily transported long distances, especially into dwellings. The larvae al- ways conceal themselves by burrowing into the cereal infested and are thus easily overlooked and carried from place to place. It is not at all surprising in view of these habits that the insect has found its way into many pan- tries. Appearance of the insect. — The larva of the Mediter- ranean flour moth is about one-half an inch in length and has a cylindrical, flesh-colored body with a pinkish cast. The body is sparsely clothed with long hairs and the head is reddish-brown in color. The larva has the three pairs 244 HOUSEHOLD INSECTS of true legs on the thorax and four pairs of fleshy ones along the underside of the abdomen and a single pair at the hind end of the body. The adult is a dark-colored moth (Plate IV) varying from one-half an inch to three-quarters of an inch in length when at rest. When the wings are expanded they measure from three-fourths to an inch across. When at rest the wings are folded along each side of the body while the tip of the abdomen is often turned upward between the ends of the wings. The front wings are rather dark gray and crossed near the tips with dark, wavy lines and not far from the bases with a wavy, W-shaped line. The hind wings are silver gray. Both wings are heavily fringed with long hairs. Habits, injuries, and food. — The larva? have the very bad habit of spinning silken threads wherever they go. Moreover, they are constantly crawling here and there through the flour, bran, or other material upon which they are feeding. The result is that the material becomes webbed together with the silken threads. In mills, where the larvae are present, the flour becomes webbed together in such masses that the spouts and machinery become clogged and unable to run. When once the flour in a barrel or the bran in a sack becomes thoroughly infested with these larvae the whole mass will be filled with their webs and so matted together that it becomes practically unfit for anything save to feed to stock. They are much more injurious in mills than in private dwellings. It seems that these insects are more fond of rice flour and products than of anything else. Buckwheat flour is also verv attractive to them. However, when driven PLATE IV Indian-meal moth above, enlarged; Mediterranean flour-moth (X 3) and eggs (X 5) in middle; pupae of Mediterranean flour-moth, below. INSECTS INJURIOUS TO CEREALS 245 to it they will eat almost anything. We have had a colony of them living on corn in the ear in the insectary for several years. The larvae seem to thrive upon the corn and go on reproducing the whole year through. Life history. — The egg is elongated, oval in shape, and when first laid almost white, but later it turns brown and becomes wrinkled. The egg is visible to the unaided eye, but so small that it takes forty to fifty of them, placed end to end, to reach an inch. In our cages the eggs were deposited on paper and cloth and on the sides of the glass tumblers in which the moths were confined. It takes the eggs from five to ten days to hatch after being deposited. When the caterpillar first emerges from the egg it is only about one-twenty-fifth of an inch long. But it eats a great deal and grows rapidly, so that in midsummer it becomes full-grown in 25 to 40 days. In early spring and late fall, when the temperature is lower, it takes longer for the larva to mature. When the larva is full-grown, it spins a very fine thin cocoon of silk and within this changes to a pupa. The cocoon is usually fastened to some surface, and often particles of flour and meal are mixed with the silk. The pupa rests quietly for ten or fifteen days and then its skin splits open along the back and the moth crawls out, dries its wings, and perhaps flies to other parts of the house. The female moth is soon ready to deposit her eggs, which in our cages were laid mostly at night. Sometimes the eggs are laid singly and sometimes in chains of eight or ten. Johnson has shown that a single moth may lay as high as 271 eggs with an average of about 240. Under natural conditions in the East there are probably 246 HOUSEHOLD INSECTS four broods a season. In the South and in California there may be more. If infested material is stored in a warm pantry or kitchen, the insects will breed all through the year. Methods of control. — In mills, where the work of extermination is done on a large scale, fumigation with hydrocyanic acid gas is often resorted to. In the case of a pantry this might also be done. First, however, all of the walls of the storage bin should be gone over with a stiff brush and just as many of the larvse and pupae dis- lodged, swept up, and burned as possible. Then the sacks of infested material should be separated so that the gas will have access to all sides of them. The same care to make the room as tight as possible should be exercised as was advised in the chapter on bedbugs. It has been found that freezing will kill all forms of this insect, but the temperature must be zero or below and must continue for four or five days. It is also important to follow this freezing quickly with warm temperatures. It seems that the severe cold followed by high temperatures is more effective than prolonged, even, cold temperatures. Wherever conditions are such that this method can be used the insect may be exterminated. Carbon bisulfide may be used if desired to spray the infested sacks and masses of flour or other cereal and to fumigate a storage bin or pantry. If used to fumigate, the room should be made tight, and two pounds of the liquid to each 1000 cubic feet of space should be used. The gas from carbon bisulfide is inflammable and no lights of any kind should be brought near the room which is being fumigated. Probably the most economical way to follow in a private INSECTS INJURIOUS TO CEREALS 247 dwelling is to feed the infested flour, meal, or other cereal to stock and then to brush down all the larvae and pupae and burn them. Then spray the walls of the storage bins thoroughly with kerosene oil, being sure to force it into all the cracks and crevices of the walls and floors. This will kill eggs, larvae, and pupa?. With care and persistence this moth can be exterminated from the house, but the pantry is liable to be reinfested with it at any time for, as we have said, it is present in most flour mills and there is little hope of its ever being exterminated. REFERENCES TO ECONOMIC LITERATURE ON THE MEDITERRANEAN FLOUR MOTH 1879. ZELLER, P. C. —Ephestia kuhniella n. sp. Stettiner Entomo- logische Zeitung, pp. 466-471. 1887. LINTNER, J. A. — Ephestia kuhniella as a pest in mills. N. Y. State Mus. of Nat. Hist., 39th. An. Kept., p. 99. 1893. DANYSZ, J. — Ephestia kuhniella, parasite des bles, des far- ines, et des biscuits. Histoire Naturelle du Parasite et Moyens de le detruire. Memoires du Laboratoire de Parasitologie V6ge"tale de la Bourse de Commerce, Vol. 1, Paris. 1894. JOHNSON, W. G. — The Mediterranean flour moth. Appen- dix to the nineteenth report of the State Entomologist of Illinois. 1896. CHITTENDEN, F. H. — Development of the Mediterranean flour moth. Bull. 6, n.s., Bu. Ent., U. S. Dept. Agri., pp. 85-88. 1896. QUAINTANCE, A. L. — The Mediterranean flour-moth. Bull. 36, Fla. Expt. Stat., p. 363. 1904. WASHBURN, F. L. — The Mediterranean flour moth. Special Kept, of the State Ent. of Minn., St. Anthony Park, Minn. 1910. CHITTENDEN, F. H. — Control of the Mediterranean flour moth by hydrocyanic acid gas fumigation. Circ. 112, Bu. Ent., U. S. Dept. Agri. For further references to literature on this insect see the paper of Johnson referred to above. 248 HOUSEHOLD INSECTS THE CONFUSED FLOUR-BEETLE Tribolium confusum Flour, meal, and prepared cereals of all kinds, are often infested with tiny reddish-brown beetles about one-eighth of an inch in length. In most cases one may be quite sure these are the confused flour beetles although in addi- tion to their being confused with the rust-red flour-beetle one is liable to mistake the saw-toothed grain-beetles for them unless closely examined. The confused flour-beetle (Fig. 77) has a flattened, oval body with the head and thorax, on the top sides, densely covered with minute round punctures. The saw-toothed grain-beetle has a long, slender body, and the edges of the thorax are beset with tooth-like projections which dis- tinguish it at once, when closely ex- amined, from this flour-beetle. The confused flour-beetle occurs all over the United States, although it is an introduced species. Chittenden says that within two years from the time it was recognized in this country as a distinct species it was reported as injurious from almost every state and territory in the Union. We have received many complaints regarding this pest in various cereals. It was reported not long ago in oatmeal flour and has been breeding all winter in this material in our insectary. At this writing the flour is one mass of the tiny larvae and adult beetles. They have FIG. 77.- — The con- fus3d flour-beetle. (X 12.) INSECTS INJURIOUS TO CEREALS 249 evidently bred freely during the winter months in the warm room. One of the large powdered food manufacturing com- panies sent us specimens of this beetle and the larvae and said that they were found generally in their factories. The writer reported as follows on the habits of the insect ; "They are found usually in cracks or under cover, seldom being seen in the open. The bugs eat wheat flour and unground wheat malt, wrhile the worms eat the ground malt and our unfinished product. It seems that both are attracted by the sugar content of the material, as they are not found in a certain portion of it which does not contain sugar, with the exception of the wheat flour." The larva of this flour-beetle resembles a miniature yellow meal-worm. Of course, it is very much smaller, being only about one-fourth of an inch in length. Its body is hard and of a shining brown color, except at the joining of the segments, where it is lighter in color. Where the larvae are abundant they mat the flour together in hard masses and in these masses one will find the adults, larvae, and pupae. The confused flour-beetle is a pest in mills as well as in houses. W. G. Johnson, in the different issues of the American Miller, gives considerable data regarding this beetle as a pest in mills. In the issue of this periodical for Jan. 1, 1896, he says that it was the most troublesome mill pest of the year 1895 and estimates that it had cost the millers of the United States over $100,000 in manu- factured products during that one year. The beetles and the larvae are general feeders, for they are found in the cereals, in corn-meal, oatmeal, flour, and Chittenden says in ginger, cayenne pepper, baking powder, 250 HOUSEHOLD INSECTS orris root, snuff, slippery elm flour, peanuts, peas, beans, and seeds of various kinds that are stored a long time. They are also pests in the museum, for they attack the bodies of insect specimens. Chittenden cites an instance in which a whole consign- ment of baking powder was lost through an infestation by this insect. It seems that wheat flour had been used to adulterate the powder and probably it was this that attracted the insects. The boxes had all been wrapped tightly with paper so that they were practically air-tight. The beetles must have gained access to the powder in the factory before the boxes were closed. The life history of this pest has not been completely worked out and it is not clearly understood. The small white eggs are laid in crevices of the receptacle or are attached to the sides of thejbags or boxes or other con- venient surface. It would appear, from our own observa- tions, that they are laid among the cereal on which the beetle is working, especially on the hard lumps of which we have spoken. These hatch into the tiny white larvae, which later become light brown in color. The larvae probably attain their growth in about four weeks and then change to pupae. Chittenden found that the insect passed through its whole life cycle in about thirty-six days. He estimated about six days as the period of incubation and about six days for the pupal period. There is evidently an opportunity for several generations during a season, and, as we have shown, they will breed in warm, evenly heated rooms all winter. Methods of control. — Many times, when the beetles become abundant in a flour bin or in wooden compart- ments in which various cereals may be stored, they are INSECTS INJURIOUS TO CEREALS 251 hard to eradicate. In such cases, all of the flour and cereals will have to be removed and the receptacles thoroughly cleaned in some manner. The beetles may often hide in the cracks, and in that case boiling water will perhaps prove the best material with which to reach them. Whenever it is feasible to fumigate the bin or storage receptacles with carbon bisulfide this will prove effective if the flour containing the beetles is thrown away or fed out. They are so small and flour is so hard to penetrate with the gas that fumigation will not reach the insects when embedded in the food material. To make doubly sure, wooden barrels, buckets, or bins might well be given a good coating of white paint inside and out as a final touch to the efforts at eradication. THE RUST-RED FLOUR-BEETLE Tribolium ferrugineum The rust-red flour-beetle is very similar to the confused flour-beetle and the two species have evidently been much confused. We have not found the rust-red species in New York, although it occurs in this latitude. It seems to be more generally confined to the Southern states, where it infests grain much as the confused flour-beetle. Its work and habits are similar to the species just discussed. J. B. Smith in his catalogue of the insects of New Jersey says that these two species occur in that state together and very often mixed with one another in the same food mass. The two species may be distinguished by differences in the antennae and in the margins of the heads. 252 HOUSEHOLD INSECTS The segments of the antennae of the confused flour- beetle gradually enlarge from the base to the tip of the antenna, thus forming a gradually clavate organ. On the other hand, the last few segments of the antennae of the rust-red beetle are much larger than the preceding ones, thus forming a suddenly clavate organ. Again, the margins of the head of the confused flour- beetle are expanded and notched or angulated at the eyes, while the margins of the head of the rust-red beetle are nearly continuous at the eyes. REFERENCES TO ECONOMIC LITERATURE ON THE FLOUR-BEETLES 1896. CHITTENDEN, F. H. — Insects affecting cereals and other dry vegetable foods. Bull. 4, n.s., U. S. Bu. Ent, pp. 113-114. 1912. GIRAULT, A. A. — Insects injurious to stored grains and their ground products. Bull. 156, 111. Expt. Stat. THE INDIAN-MEAL MOTH Plodia interpunctella The writer first became acquainted with this insect, in a practical way, as a pest in packages of raisins in his own larder. As a matter of fact, it is a common household pest and the larvae are found in all sorts of stored products. It probably finds its way commonly into houses by being brought in in supplies from grocery and feed stores. Not long ago the remains of a box of graham crackers were brought up from a grocery store for examination and determination of the kind of worms that were de- stroying this article of food. In a few days an adult moth appeared and proved to be the Indian-meal moth, as we had predicted from an examination of the larvae. INSECTS INJURIOUS TO CEREALS 253 Distribution and food. — The Indian-meal moth is widely distributed in the United States and Canada and is found in different countries in Europe. As Holland says, this insect "has a propensity to feed upon almost anything edible that comes its way." In this country one of our earliest accounts of it was by Fitch, in 1856, who called it the Indian-meal moth because he found the larvse feeding in corn-meal. The larvaB evi- dently are very fond of corn-meal, but they do not refuse grain of any kind, ground or whole. As we have already noted, we have found the larvae feeding on oatmeal, graham crackers, and raisins. Our department records also show that the larvae live upon and do much damage to stored peanuts. Popenoe records the same injury on a wide scale in Virginia and North and South Carolina. In addition, the insect has been recorded as feeding upon prunes, currants, dried apples, flour, beans, English wal- nuts, pecans, almonds, chocolate beans, dried peaches, plums, cherries, clover seed and other seeds. Appearance of the different stages. — The moth is some- what smaller than the Mediterranean flour moth and differs considerably in appearance when examined closely. The wings expand about five-eighths of an inch and the fore wings are dull white or cream-colored on their basal parts, while the outer parts of these wings are reddish- brown in color with irregular markings of blackish bands and patches. The hind wings are dusky gray with quite a long fringe of hairs (Plate IV). The larva is whitish or flesh-colored and often with a rosy or yellowish tint (Fig. 78). The head of the larva is yellowish or reddish-brown and the thoracic shield is very pale brown with a distinct pale line through the middle 254 HOUSEHOLD INSECTS dividing it in halves. The anal segment bears a pale brownish plate on the top side. Each larva has five pairs of prolegs along the abdomen, each of which is furnished with a circle of hooks at its extremity. Life history and habits. — The eggs, which are small and white and look much like those of the Mediterranean flour moth, are de- posited singly or in groups of half a dozen or more on the ma- FIG. 7». — Larva of the Indian-meal moth, terjal upon wnich the enlarged. . , insects happen to be living. It is said that a single female moth may lay as many as 350 eggs. The eggs hatch in about four days if the room is warm and the larvae in a warm room may mature in three weeks or possibly in less time. Some larvae that wre collected on September 19th, 1911, occupied over two months in reach- ing their full growth. Of course the temperature varied a great deal and probably averaged lower than in mid- summer. The larvae are very active and can crawl backwards as well as forwards. While they are growing they crawl about a great deal and have the same pernicious habit of the Mediterranean flour moth of spinning a web wTher- ever they go, which entangles the particles of food, binds them together in a webbed mass, and makes the material unfit for food. When the larvae become full-grown they crawl away in search of some fold in a bag, crack in a wall, or in the floor, or some other nook in which to ensconce themselves. Here they spin cylindrical white silken cocoons and change INSECTS INJURIOUS TO CEREALS 255 to pupae. The pupse lie quietly in their cocoons for a week or ten days, at the end of which time the moths emerge. Under favorable conditions of an abundance of food and the right temperature the whole life cycle from egg to moth may be passed in four or five weeks. There is consequently time for four or even more generations in one year. In fact, in a warm room they may breed all the year through. In cold rooms, however, the larvae remain quietly within their cocoons all winter, not chang- ing to pupse until warm weather of the following spring. Natural enemies. — The Indian-meal moth seems to have a number of natural enemies. The two hymenop- terous parasites, Omorgus frumentarius, and Hadrobracon hebetor, are considered the most important. Popenoe says that these two forms do a great deal toward holding the pest in check. Methods of control. — The Indian-meal moth is so much like the Mediterranean flour moth in habits, injuries, and in the kind of food that it eats that the same methods used to control and exterminate the latter may be used for the former. REFERENCES TO ECONOMIC LITERATURE ON THE INDIAN-MEAL MOTH 1856. FITCH, ASA. — The Indian-meal moth, Tinea zeae. Second Kept, on noxious and beneficial insects of New York, p. 320. 1890. RILEY and HOWARD. — Indian-meal moth in Kansas. Insect Life, Vol. 2, p. 277. 1894. STEVENSON, H. A. — An attack of Ephestia interpunctella. 25th Ann. Rept. Ent. Soc. Ont, p. 57. 1896. CHITTENDEN, F. H. — Principal household insects of the United States. Bull. 4, Bu. Ent., U.S. Dept. Agri., p. 118. 1896. QUAINTANCE, A. L. — The Indian meal-moth. Bull. 36, Fla. Expt. Stat., p. 364. 256 HOUSEHOLD INSECTS 1897. CHITTENDEN, F. H. — Some insects injurious to stored grain. Farmers' Bull. 45, U. S. Dept. Agri., p. 9. 1906. BRITTON, W. E. — Ravages of the Indian-meal moth in a seed warehouse. Fifth Kept, of Ent. of Conn., p. 252. 1911. POPENOE, C. H. — The Indian-meal moth and weevil-cut peanuts. Circ. 142, Bu. Ent., U. S. Dept. Agri. THE MEAL SNOUT-MOTH Pyralis farinalis So far as the experience of the author goes, this insect is not as common a pest in households as the two which we have just discussed. However, it is often found in cereals, sometimes in flour, and meal, and often injures clover hay while stored in stack or barn. It is quite probable that its original sources of food consisted of dried grass or plant stems. It does not seem to be very fastidious regarding the kind of food it has, for it apparently relishes equally well straw, husks, bran, and seeds, whole or ground. The moth. — The moth is much more striking and handsome in appearance than either the Indian-meal moth or the Mediterranean flour moth. Its wings expand about four-fifths of an inch, but they are wider than those of the two moths just mentioned, especially the hind ones. The front wings are rather conspicuously marked. They are light brown in color, but at the tip and base of each there is a chocolate-brown spot, each one edged with a curved white line that extends clear across the wing (Fig. 79). The moth is usually found near the material infested by the larvae, but very often it is seen clinging to the ceil- INSECTS INJURIOUS TO CEREALS 257 ings of rooms with the end of its abdomen curved over its back. The larva and its habits. — The larva is somewhat similar in appearance to those of the other two cereal moths. It is whitish or flesh-colored, somewhat darker at either end, and its head is reddish. It builds long tubes in the material on which it is feed- ing by binding the particles together with silk. In these tubes it lives and wholly conceals itself. When the larva has completed its growth it leaves the tube and finds a place in which to spin its cocoon, within •'^a^irf A which it transforms to a PuPa- It would seem that the life history of this insect FlG- 7Q(~ has not been carefully worked out, and there remains considerable uncertainty regarding the length of time necessary for a generation or the number of generations in a year. Chittenden says that some experiments he was then conducting went to prove at least four generations a year. He had carried the species through all of its stages in the spring of the year in eight weeks. Methods of control. — When this pest is found in stored grain it can be destroyed by the use of carbon bisul- fide. The liquid should be poured in a shallow dish and set on top of the grain in the box or bin. The receptacle should then be covered tightly with old blankets and allowed to stand two or three days. 258 HOUSEHOLD INSECTS If flour, meal, or other cereals become badly infested and the larvae build their tubes all through it, the material will probably have to be fed to stock or thrown away. In other cases the same methods of control will avail for this insect that were described as efficient for the control of the Mediterranean flour moth. REFERENCES TO ECONOMIC LITERATURE ON THE MEAL SNOUT-MOTH 1889. RiLEY-HowARD. — Range of Pyralis farinalis. Insect Life, Vol. 2, p. 194. 1893. OSBORN, HERBERT. — Methods of treating insects affect- ing grasses and forage plants. Insect Life, Vol. 6, pp. 72, 78, 193. 1895. CHITTENDEN, F. H. — The more important insects injurious to stored grain. Yearbook, U.S. Dept. Agri., 1894, p. 286. 1894. OSBORN, HERBERT. — The clover-hay worm. Bull. 32 (old ser.), Bu. Ent., U. S. Dept. Agri., p. 49. 1896. CHITTENDEN, F. H. — The principal household insects of the United States. Bull. 4, Bu. Ent., U. S. Dept. Agri., p. 119. 1896. QUAINTANCE, A. L. — The meal snout-moth. Bull. 36, Fla. Expt. Stat., p. 362. 1897. CHITTENDEN, F. H. — Some insects injurious to stored grain. Farmers' Bull. 45, U. S. Dept. Agri., p. 10. 1900. FLETCHER, JAMES. — Notes from Canada. Bull. 26, Bu. Ent., U. S. Dept. Agri., p. 96. THE GRANARY WEEVIL Calandra granaria Nearly every kind of small insect that is found in stored grains and cereals is commonly called a weevil. Really there are only two insects that frequent these food-stuffs that should properly be called weevils and these are the INSECTS INJURIOUS TO CEREALS 259 small snout beetles known as the granary weevil and the rice weevil. Both of these beetles resemble each other very closely in size, shape, and general appearance. They are both widely distributed in this country, although the first one, C. granaria, is a more cosmopolitan species than the second. The granary weevil is a very old offender, for it has been known as a grain weevil from the earliest times. It has been an inhabitant of houses, barns, and granaries so long that it has actually lost the use of its wings and is now strictly an indoor species. It is probably present in every state in the Union, for it has become widely distributed by being carried in the grains which it infests. It is undoubtedly more abundant in the warmer parts of the country, where it breeds the year round. It is injurious to wheat, corn, barley, and other grains. We have found it in shredded wheat biscuits, even on Pullman dining cars, where one pays for the best quality of foods. It sometimes finds its way pearl barley, which is used in soups. The mature beetle is about one-eighth of an inch long and of a shining chestnut-brown color. It has a long slender snout, or proboscis, on the end of which is a pair of tiny but very efficient jaws. The thorax is marked with shallow oval punctures, while the wing covers are grooved and ridged lengthwise and are uniformly brown (Fig. 80). FIG. 80. — The granary weevil. (X 17.) into households in 260 HOUSEHOLD INSECTS The female weevil gnaws a tiny hole in a kernel of wheat or corn and then deposits an egg in it. The egg hatches and the small white grub lives inside the kernel, eating out the dry inner portions. In a kernel of corn there may be several individuals, but in a grain of wheat or barley there is room for but one. The larva is short, fleshy, and footless. When the larva becomes full-grown it changes to a white pupa with the proboscis, legs, wing pads, and antennae plainly developed. The whole life cycle may be passed under favorable conditions in about six weeks, but the period will vary with the temperature and time of year. In the fall and winter it is liable to be greatly prolonged. Under favorable conditions there may be three or four broods in New York in a season, but in the extreme South there may be six or more. If the infested grain is kept in a well-heated room, the weevils may breed all the season through. It is said that the granary weevil is very prolific, with the egg- laying extending over a long time and many eggs being deposited. It has been estimated that a single pair of weevils may, in a year, give rise to 6000 descendants. Thus a pair of these insects with their progeny may cause a good deal of damage in a comparatively short time. The mature weevils have the habit of feeding on the grain, gnawing into the kernels for food and shelter, and since they are long-lived insects, they probably cause as much injury as the larvse. A curious, interesting, and perhaps important bit of knowledge concerning this insect is the fact that it has been used successfully as a substitute for the Spanish blister-beetle (Cantharides) with this added advantage, that it does not produce strangury. It was apparently INSECTS INJURIOUS TO CEREALS 261 used for this purpose in the South, perhaps during the war, when the Spanish beetles were not obtainable. So far as the author is aware, however, the granary weevils are not generally used for that purpose at present. Cantharadin is a most dangerous and violent drug to take internally. It is quite possible that the finely ground bodies of the granary weevils, since they seem to possess much the same qualities as the Spanish flies, are also dangerous when taken into the alimentary canal. In that case, flour containing the pulverized bodies of these insects might prove seriously injurious to persons eating it. Undoubtedly flour is often made from wheat that is badly infested with these weevils. THE RICE WEEVIL Calandra oryzae The rice weevil seems to have originated in India, whence it has spread to all parts of the world. Because it was first found in rice it has always been known as the rice weevil. It is undoubtedly the more important and more injurious weevil of the two in this country, although it may not be as widely distributed as the first one. It occurs especially in warm countries and for that reason is very abundant and in- jurious in our Southern states. The rice weevil is very similar in appear- ance to the granary weevil. It is just about the same size, with a similar proboscis, but .' 81-~T?e , i 11 i • i • weevil. varies m being dull brown m color in con- (x 7.) 262 HOUSEHOLD INSECTS trast to the shining brown of the granary weevil. Perhaps the most obvious difference by which the two weevils may be readily separated is the fact that the wing covers of the rice weevil have four red spots, one on each outer corner, as shown in the illustration (Fig. 81). The thorax of the rice weevil is closely pitted with round punctures in contrast to the oval, shallow punctures present on the thorax of the granary weevil. Moreover, the wings of the rice weevil are well developed and the insect can fly very readily. The rice weevil is more apt to be found in households than the granary weevil, for it feeds upon the grains of rice and often invades boxes of crackers, cakes, and other bread- stuffs, and is found in barrels of flour and sacks of meal. The eggs are laid within a kernel of corn or grain of wheat, where they hatch in about three FIG. 82. — Larva of the rice , r™ , • i. t * A weevil, (x 10.) days. Ihe larva is short, tat, and whitish (Fig. 82) and lives within the grain for about sixteen days, when it trans- forms to a pupa (Fig. 83) which remains quietly within the grain from three to nine days. The adult beetle does not emerge from the grain as soon as it is formed, but remains within the kernel eating out the inside for several days. The life cycle is usually passed, under favorable conditions, in about thirty-five days. The adults are found in the fields during the summer, espe- cially on the ears of corn. In the autumn they migrate to the barns and granaries where their food is stored. Methods of controlling the grain weevils. — The most INSECTS INJURIOUS TO CEREALS 263 effective method of dealing with the grain weevils is by the use of carbon bisulfide. It has been shown, by recent experiments, that this liquid should be used at the rate of 2 or 3 pounds to every 1000 cubic feet of space. One of the best methods of keeping seed corn, seed peas, beans, popcorn, and other seeds, is to store them in tight dry goods boxes. The boxes should be filled within 3 or 4 inches of the top. When infested with the weevils, the required amount of the carbon bisulfide may be poured into a shallow tin basin or pan and set on top of the grain. The top of the box should then be covered with two or three heavy blankets to keep in the fumes. The liquid will readily evaporate and the heavy gas will settle down through the grain killing everything in it. The precaution should be taken of not going near the boxes with a lighted FIG. 83. — Pupa of lantern or fire of any kind until after gfjg* weeviL the blankets have been removed and the gas has dissipated itself in the surrounding atmosphere. Of course, where a cereal or box of crackers is found to have become infested by the weevils it may be necessary to throw them away entirely. An infested pantry or storeroom should be carefully cleaned and all the rem- nants of material that may be attractive to the weevils thrown away. If a storeroom is so situated that a continuous heat of 130 degrees can be maintained for several hours, the weevils in all of their stages may be killed. 264 HOUSEHOLD INSECTS REFERENCES TO ECONOMIC LITERATURE ON THE GRAIN WEEVILS 1869. WALSH, B. D., and RILEY, C. V. — Poisonous flour. Amer. Ent, Vol. 1, p. 179. 1897. CHITIENDEN, F. H. — Some insects injurious to stored grain. Farmers' Bull. 45, U. S. Dept. Agri., pp. 4-6. 1911. HINDS, W. E., and TURNER, W. F. — Life history of the rice weevil (Ccdandra on/zee) in Alabama. Jr. EC. Ent., Vol. 4, pp. 230-236. 1912. SANDERSON, E. D. — Grain-weevils. Insect pests of farm, garden, and orchard, pp. 186-187. 1912. GIRAULT, A. A. — Insects injurious to stored grains and their ground products. Bull. 156, Illinois Expt. Stat, pp. 80-81. FRUIT-FLIES Drosophila sps. Fifty-nine species of the genus Drosophila have been listed as occurring in North America. Over thirty of these have been recorded from the United States. Some of these species, as D. funebris, D. graminum, and D. transversa, are also common to Europe. D. ampelopkila is also recorded from South Europe and North Africa. The flies of the genus Drosophila, for the most part, breed in decaying and fermenting fruit. The slender white maggots are found in pomace, about cider mills, and they are abundant about vinegar factories, often working into the barrels around the openings. The flies are always abundant in the fall about grapes, bananas, pears, and other fruits, especially if the fruit has begun to decay. If the fruit is left standing in the pantry or on the side- board, it is almost sure to become infested with these tiny flies, and no amount of ordinary screening will keep them out because they go through the meshes of common wire INSECTS INJURIOUS TO CEREALS 265 screens. They are also abundant in decaying fruit in apple orchards and their larvae are sometimes mistaken for those of the apple maggot, Rhagoletis pomonella. It should be said that not all of the species of the genus Drosophila live in fruit. Some of the species mine in the leaves of plants, especially cabbages and radishes. These species have been separated from the genus by some au- thorities and placed in the genus Scaptomyza. Most authors, however, recognize this only as a subgenus. FIG. 84. — A fruit-fly (D. ampelophila). (X 10.) Probably the most common species of fruit-flies in this country are D. ampelophila (Fig. 84) and D. amcena. These are about one-eighth of an inch in length, but their wings are rather large proportionately. Their bodies are reddish-brown in color and clothed with rather stiff hairs. The tiny, white, elongated egg is deposited by the female in the soft pulp of the decaying fruit. During the month of October Comstock found the duration of the egg stage to be from three to five days. The larva is a slender white maggot about j of an inch in length. It takes from three to five days for it to mature. When full-grown it changes to a brownish pupa (Fig. 85) 266 HOUSEHOLD INSECTS within or about the apple. It does not go into the ground like the larva of the apple maggot. The pupal stage lasts three to five days also, and the adult fly is ready to de- posit eggs within two or three days. Thus a single genera- tion of these fruit-flies may be produced in eleven days. The larvae of the fruit-flies are some- times injurious to grapes on the vines. W. L. Devereau of Clyde, New York, found that these maggots completely ate out the insides of grapes first injured by being pecked by birds while still hanging on the vines. Moreover, the maggots actually bore from one grape to another. Forbes relates the same habit of the larvae at Moline, Illinois. He says they attack most frequently the grapes that have been injured by birds or rot, and after once having begun on a cluster they bore from one grape to another, while the adults are FIG. 85. — Pupa constantly depositing more eggs, thus ^iiedUit"fly> fina% destroying all of the berries in a cluster. The maggots not only attack decaying fruit, but they are often found in canned and pickled fruits. Bowles says that he found the maggots in an earthen jar that had been nearly filled with raspberries and vinegar prepared for the purpose of making raspberry vinegar. On open- ing the jar ten days afterward it was found swarming with the larvae and pupae of the fruit-fly. Hundreds of the maggots were crawling about on the under side of the cover and on the sides of the jar. He further states that he has seen the flies hovering about the corks of wine jars, INSECTS INJURIOUS TO CEREALS 267 evidently trying to find an opportunity to deposit their eggs on the contents. In fact, he placed a few rasp- berries in a small quantity of vinegar in a jar with a loose cover. A fortnight afterward he found a number of larvae inside the jar and several pupae attached to its sides. Evidently these pests search for cracks and crevices through which to enter and find their way to their food. Probably the flies often deposit their eggs around the edges of covers to jars, and the maggots, when they hatch, manage to work their way through small openings into the fruit. Lintner relates an instance of a species of Drosophila breeding in flour paste. A correspondent wrote him, say- ing : " I send a package containing larvae of a fly very troublesome around my cellar and pantry. These I found in a little paste that I had set aside for a short time. I could not obtain the flies, but presume that they will be produced from the larvae. They are very partial to anything in a state of fermentation, and if my pickled fruit or jam begins to sour, they find it before I do, and frequently the entire top of the fruit seems alive with the larvae, although they never go deep into the jar." The flies emerged, but Lintner judged them to be a new species and not the D. ampelophila, which was probably the species referred to by the correspondent as infesting his pickled fruit. Cockerell found the Drosophila flies prevalent in the Salt River Valley of Arizona in orange orchards and he con- cludes that it may be responsible for spreading the black rot of the navel orange. He argues that since the flies breed in the rotting oranges they no doubt become dusted with the spores of the fungus and carry them to the open 268 HOUSEHOLD INSECTS ends of sound oranges, where infection might take place. Methods of control. — It has been our experience that ordinary wire screen, say 12 or 14 meshes to the inch, does not prevent these flies from entering a house. Pos- sibly wire screen with 16 meshes to the inch might keep them out. We doubt the practicability of effectually screening these flies from houses on account of their small size. It is evident from their habits of entering crevices and cracks of fruit jars that, in order to exclude them, the jars must be hermetically sealed, or practically so. All fruit that is canned while hot and then hermetically sealed with rubber bands or otherwise will be safe from the attacks of these flies. Pickled fruits in stone jars with loose tops are subject to attack by these flies. Jars of fruit that are opened now and then and left loosely covered must be placed inside of some tight receptacle for protection where these fruit flies are present. In case the maggots have gained access to a jar of fruit it is not necessary to throw away the whole jar since the larvae occur only among the top layers. The infested portions may be thrown away when the remainder will be found free from the maggots and usually in perfectly good condition. Fruit, if left standing in the pantry, kitchen, or on the sideboard, must be kept free from all decayed specimens or must be tightly covered from the flies. It is not so much the destructiveness of the flies that we desire to avoid in these cases as it is the annoying presence of them in our pantries and dining rooms. They are always suggestive of overripe and decaying fruit. INSECTS INJURIOUS TO CEREALS 269 REFERENCES TO ECONOMIC LITERATURE ON THE FRUIT-FLIES 1882. LINTNER, J. A. — The pickled fruit-fly. First Report, pp. 216-221. 1882. BOWLES, G. J. — The pickled fruit-fly, Drosophila ampeloph- ila. Can. Ent., Vol. XIV, p. 101. 1882. COMSTOCK, J. H. — The pomace-flies. Report of the U. S. Entomologist for 1881, p. 198. 1896. HOWARD, L. O. — The fruit-flies or vinegar flies. Bull. 4, U. S. Dept. Agri., Bu. Ent., p. 109. 1899. COCKERELL, T. D. A.— The Drosophila fly. Bull. 32, Arizona Expt. Stat., p. 290. OCCASIONAL PESTS OF THE PANTRY There are two weevils that occur in peas and beans that are liable to be found in the household among these edibles. One of them is often found in numbers in stored beans, for it breeds among the beans and badly injures them. The pea weevil, Bruchus pisorum, is about one-fifth of an inch in length and the wing covers are marked with white and black spots. It is an old enemy to peas and does considerable injury farther South. The adult beetle deposits its eggs singly on the surface of the young pods in the field. The egg hatches and the young larva bores through the pod and enters one of the green peas. Many times every pea in a pod is infested. In these cases we certainly often eat one or more of the larvae in the green peas, for each one remains practically invisible within the pea. The bean weevil, Bruchus obtectus (Fig. 86), is somewhat smaller than the pea weevil and is not so conspicuously marked, although the wing covers are mottled with light and dark spots. 270 HOUSEHOLD INSECTS The bean weevil, besides laying its eggs in beans in the field and developing there, also breeds in beans after they are harvested and stored. In stored beans they cause an immense amount of damage, often destroying them for either food or seed purposes. It also breeds in dried peas, causing similar injury. Stored beans may be protected from this weevil by the use of carbon bisulfide or heat, as already described in the case of the grain weevils. The broad-horned flour-beetle (Echocerus cornutus) is occa- sionally found in houses. In Europe it Is reported as a pest in bakeries. It seems to get into the flour and into the dough that accumulates on the molds used in baking bread. The species does not seem to be widely distributed in the United States, although it is fairly common on the Pacific Coast. In California it occurs both indoors and outside under bark. It is, therefore, firmly established and acclimatized in that region. It has been reported from the Pacific Coast in all stages of development in ground cereals of the stores. The beetle itself, especially the female, resembles closely the confused and the rust-red flour-beetles. The male, however, possesses broad mandibular horns, that dis- tinguishes it at once from the two flour-beetles mentioned. The habits and food of the broad-horned flour-beetles FIG. 86. — Bean weevil. (X 8.) INSECTS INJURIOUS TO CEREALS 271 are similar to those of the confused flour-beetle. The beetles can be controlled in the same way as explained for the other flour-beetles. The coffee bean-weevil (Arcecerus fasdculatus) is another insect that may probably be looked for as a household pest. It has a world-wide distribution, having been carried all over the world through the activities of commerce. It infests the raw berries of coffee, cacao beans, mace, and other tropical vegetable products. In this country, it has been found attacking cornstalks in the field, and breed- ing in cotton bolls, in the fruit of the chinaberry tree, in the pods of the coffee weed, and in the seeds of the wild indigo plant. Chittenden records an interesting outbreak of this weevil in a grocery store in Washington, D.C. The weevils had apparently been introduced into the store in bags of coffee. They had afterwards attacked dried apples, fig cakes, and other edibles in the store. It would be easy for them to be introduced into households pur- chasing supplies from the infested grocery. There are several other insects that may occasionally be found in stored vegetable products and which may find their way, at times, into the household. It is quite likely that some of these occasional pests may become serious in some cases ; and it is easily possible that some of them may become more or less habitual household pests. Insects are constantly changing their food habits and we may expect new pests at almost any time. Chittenden, in Bulletin 96, Part I, of the United States Bureau of Entomology, gives a list of 76 different species of insects that are found in stored cereals, any one of which is prob- ably capable of becoming a household pest at any time. CHAPTER XI INSECTS INJURIOUS TO MEATS, CHEESE, AND CONDIMENTS SMOKED and dry-cured meats of nearly all kinds are subject to injury from the larvse of certain beetles, while cheese is often attacked by myriads of mites and the larvse of certain flies. Condiments, like ginger, pepper, and other spices, together with various drugs stored in the pantry, are also seriously damaged by the larvae of a few small beetles. Fortunately, most of these pests are not frequent visitors of the household. THE LARDER BEETLE Dermestes lardarius Ham, bacon, and other kinds of meats that happen to be stored in the larder are sometimes attacked by small, brown, hairy larvse, about one-half inch long when full- grown, that often cause considerable injury and become the source of a good deal of worry to the housekeeper. The larva may be recognized by its hairy body, and its meat-eating habits together with the fact that it bears two short, curved, stiff spines on the top of the last ab- dominal segment. These larvae not only attack food products, but they feed upon horn, hoofs, skins, beeswax, feathers, and hair, and, moreover, become pests upon 272 INSECTS INJURIOUS TO MEATS 273 specimens in natural history museums, often seriously injuring valuable collections. The adult is a small beetle from one-fourth to one-third of an inch long, dark brown in color, and with a rounded back and front (Fig. 87). It has a pale yellowish-brown band across the anterior half of its wing covers. There are, on this band, six black dots, three on each side of the middle line. The first name of the beetle, Dermestes, is derived from Derma, skin, and is indicative of its habits, while its specific name, lardarius, shows its taste for the pantry or larder. More- over, this beetle belongs to the same family to which the carpet beetles belong and, as we have seen, the larvae have some of the same habits as the carpet beetles, namely, eating museum speci- mens, skins, and feathers. The larder beetle is widely distributed in this country and in Europe and Asia. Some years ago, a closely allied species, D. mtlpinus, swarmed to such an extent in large skin warehouses in London and caused so much damage that a prize of £20,000 was offered for a prac- tical and effectual remedy. Evidently the habits of the whole family of Dermestid beetles are much alike. The adult beetles (Fig. 87) are often found out-doors, hiding away in nooks and crevices during the winter. We have found them hiding in crevices of the bark on trees. They enter the house in May and June and seek for food upon which to lay their eggs. If none can be found, they deposit their eggs in cracks and crevices about the pantry where the larvae, when they hatch, can find food. The larvae do not burrow into the hams they 274 HOUSEHOLD INSECTS attack, at least not at first, but tend to confine themselves to the outside. Later, after casting their hairy skins several times, they burrow farther into the meat, where they change to pupae. Moreover, they seem to prefer the fatty portions more than the lean muscular parts. It has been observed that the larvae (Fig. 88) tend to infest hams that are beginning to spoil rather than fresh ones. From the meager and fragmentary accounts of the life history of this insect that we have it may be in- ferred that the larder beetle may reproduce itself, under favorable conditions, quite fast and that there may be several generations during a season. Miss Heustis tells us that she placed four beetles, three males and one female, in a glass jar with a piece of meat on which she had found them feeding. She saw the female deposit eggs on the meat, but had to leave before they hatched. She was gone five weeks and on her return found a large and flourishing colony of larvae, most of them full-grown. Horn found that the pupal stage lasted three or four days to a week or more, depending upon the temperature. Thus it is evident that a genera- tion may be produced in the neighborhood of 45 to 50 days, and there may be four or five generations in a season. Lintner quotes the following letter from a correspondent, which gives a good idea of the injuries caused by this insect : — INSECTS INJURIOUS TO MEATS 275 "Inclosed you will find several bugs and larvae which I found destroying our bacon. Will you please tell me what they are, and if there is any way of preventing their ravages ? Our meat was mostly put in heavy meat sacks ; some was in muslin lined with paper, and a few pieces were without either. The meat wras encased in sacks about the first of March and hung up in the garret. The sides were free from them although without sacks. If there is a remedy please let us have it." Probably, in this instance, the eggs were laid on the meat before it was incased or the beetles found access to the bacon through openings or cracks in the wrapping. Methods of control. — In the first place, the adult beetles are easily seen and they may be caught by hand. This is one way of dealing with them, and, in cases where they are not too abundant, it may be the most satisfactory and eventually the most effective. Cheese is very at- tractive to the beetles and by exposing pieces of it here and there they will congregate on them and may be caught and killed by hand in considerable numbers. If this method is followed up carefully for several days, it may often prove effectual. If the beetles are abundant and there are many hiding places, the room in which they are present should be entirely cleared of food products and anything else that may interfere with the work of cleaning. The store- room should then be thoroughly cleaned and finally sprayed with benzine or fumigated with carbon bisulfide or hydrocyanic acid gas. Cheese ground up and poisoned with arsenic and then placed in the haunts of the beetles will often kill many of them. In putting away hams, and shoulders they 276 HOUSEHOLD INSECTS should be bagged just as early as possible after being cured and should be wrapped with great care. The wrapping cannot be made too tight, for the least opening or crack will allow the entrance of the beetle to deposit its eggs. If a ham or similar article of food should become in- fested with the grubs, the part containing them should be cut away and destroyed by burning or otherwise, and the remaining part of the meat treated with a dilute solution of carbolic acid. REFERENCES TO ECONOMIC LITERATURE ON THE LARDER BEETLE 1861. HORN, GEORGE H. — Notes on the habits of some coleopter- ous larvae and pupae. Proc. Ent. Soc. Phil, Vol. 1, p. 28. 1869. WALSH, B. D., and RILEY, C. V. — Museum pests. Amer. Ent., Vol. 1, p. 248. 1870. RILEY, C. V.— The larder beetle. Amer. Ent., Vol. 2, pp. 246, 308. 1873. SAUNDERS, W. — The bacon beetle. Can. Ent., Vol. 5, pp. 171-172. 1874. WILLIAMS, JOSEPH. — The bacon beetle. Fourth Rept. Ent. Soc. Ont. for 1873, pp. 26-27. 1878. HEUSTIS, CAROLINE E. — Some observations on Dermestes Can. Ent., Vol. X, pp. 141-142. 1888. LINTNER, J. A. — The bacon beetle attacks comb. Bee Keepers' Magazine, May, 1888, Vol. XVI, pp. 143-144. 1889. FERNALD, C. H. — Household pests. Bull. Mass. Hatch Expt. Stat., No. 5, p. 6. 1890. LINTNER, J. A. — The bacon beetle. Sixth Rept. N. Y. Ins., pp. 119-123. 1894. PERKINS, G. H. — Household pests. Eighth Ann. Rept. Vt. Agri. Expt. Stat., pp. 125-126. 1896. HOWARD, L. O. — The larder beetle. Bull. 4, n.s., Bu. Ent., U. S. Dept. Agri., pp. 107-108. 1906. LOCHHEAD, WM. — Household insects. Can. Ent., Vol. 38, p. 68. INSECTS INJURIOUS TO MEATS 277 THE RED-LEGGED HAM BEETLE Necrobia rufipes This is a small steel-blue beetle (Fig. 89) scarcely more than one-fifth of an inch in length. Different individuals vary considerably in size and many of them are less than one-fifth of an inch in length. The legs of this beetle are reddish colored, hence its name red- legged ham beetle. Most of the beetles belonging to the family of this ham beetle live upon flowers or on living animal matter, but the ham beetle seems to prefer dead animal matter as food. The beetles are found about dead animal matter in fields or other situations. The larvae of this beetle have been guilty and are still guilty of causing serious damage to stored hams, although they are not confined to this class of meat. Life history. — The beetle normally feeds and spends its life history on dead animals in the field. However, in May or June the adults which emerge at this time probably often find their way into storerooms and pantries. Here the mother beetle deposits her tiny eggs upon ham if she can find this meat accessible. These small whitish eggs, twenty-five of which would not reach more than an inch, soon hatch into tiny white grubs, each with a brown head and two small hooks or tubercles at the tip of the body. The grubs burrow into the outside FIG. 89. — Red-legged ham beetle. (X 8.) 278 HOUSEHOLD INSECTS layers of fat just beneath the rind and grow rather rapidly, for they are ravenous eaters. As they multiply and grow they seem to have a great fondness for the hollow in the bone at the butt end of the ham, for they congregate here in numbers. When full-grown the grubs are darker in color, slightly over half an inch long, and have a number of brown patches on the upper sides of their bodies (Fig. 90). When the larva gets ready to trans- form it makes a curious and interesting cocoon in a rather novel way. The larva leaves the fatty portions and gnaws its way either to the harder, more fibrous parts of the ham or maybe into a near-by beam. Here it makes a glistening white cocoon that looks much like paper. The cocoon is FIG. 90. — Larva of not made from silk like the cocoons the red-legged ham <• . • i IP beetle, enlarged. of most insects, but IS Composed of small globules spit out of the mouth of the larva. These globules adhere to each other and when dry form the paper-like cocoon. Dealers in hams and other meats have given this insect the name of "paper worm" from the appearance of the cocoon. Riley says that there are probably several broods a year, but that it always passes the winter as a larva. Distribution and injuries. — This ham beetle is widely distributed over this country and is also found in Europe, Australia, Africa, and the East Indies. Nearly all of the specimens in our University collection came from the Western states, for it seems to be more abundant in the western and southern portions of the United States. INSECTS INJURIOUS TO MEATS 279 Unlike many of the household pests, the ham beetle is not present and injurious the greater part of every season, but it appears occasionally in a ham or two and when destroyed may not be seen again for years. Its most serious injuries are caused to stored meats in warehouses. It occasionally becomes established unawares in large storehouses and the infested hams are shipped to retail dealers, who in turn deliver them to private households. Since these hams are tightly wrapped, the dealers may be wholly unconscious of the infestation. C. V. Riley gives some interesting accounts of the work of this insect on hams in storehouses. He cites the case of S. S. Pierce & Co., of Boston, who ordered twenty tierces of hams from S. Davis, Jr., & Co., of Cin- cinnati during April and May, 1873. The hams were received and hung without examination in a dry, airy loft, where they remained until the following August. They were then examined and found full of worms. It seems probable, in view of the fact that the hams had been kept closely wrapped, that they were infested with the eggs of the beetle before leaving the packing house in Cincinnati. However, as this could not be definitely proven, Pierce & Co. were not able to collect damages from the packers. He also cites the case of Francis Whittaker & Sons, St. Louis, who suffered severe loss through the injuries com- mitted by this insect. The principal injury to the hams was done in this case around the end of the prominent shank bone. Here the canvas had become weak and worn through, giving the beetles access to the meat. Moreover, it seems that the Company had been in the habit of wrapping their hams a little too late in the spring. 280 HOUSEHOLD INSECTS Methods of control. — In the household this insect is not a serious pest. Moreover, the injury is not so great as it, at first sight, may seem. If a ham should become infested, the outer meat containing the worms could be cut off and thrown away. The inner meat usually remains sweet and unaffected and is perfectly good to use. When a ham comes from the dealer infested, it can, of course, be returned at once. In the case of packers and wholesale dealers the hams should be wrapped early in the season, before the first of May, with a strong canvas that will not break through or wear away. Great pains should be taken to close up all cracks in the wrapping so that no places will be left through which the beetles may gain access to the meat. REFERENCES TO ECONOMIC LITERATURE ON THE HAM BEETLE 1874. RILEY, C. V. — Red-legged ham-beetle. Sixth Ann. Rept. of the State Ent. of Mo., p. 96. 1896. HOWARD, L. O. — The principal household insects of the United States. Bull. 4, Bu. Ent., U. S. Dept. Agri., p. 105. 1905. KELLOGG, V. L. — American insects, p. 270. THE CHEESE AND HAM MITES Tyroglyphus hngior, T. farince, T. americanus, et al. Cheese, hams, and various other food products are often infested with enormous numbers of minute, pale-colored, eight-legged creatures, known as mites. These creatures are not true insects, for they have eight long legs (Fig. 91) and differ in other ways from their six-legged cousins. Near relatives of these mites are the common ticks that occur on dogs and cattle. These mites have a long list of INSECTS INJURIOUS TO MEATS 281 food substances which they attack as opportunity affords. They often occur in sugar, especially raw sugar, in great numbers and are therefore sometimes called sugar mites. It is these tiny mites (Fig. 94), abundant at times in grocery stores, that cause the disease known as "grocer's itch." The malady is induced by the presence of the mites on the hands of those working among mite-infested food products. The materials attacked by these pests in- clude flour, hams, dried meats, sugar, cheese, hair in furniture and mattresses, grains, cereal foods, drugs, dried fruits, seeds, bulbs, roots, and feathers. One species, at least, is a serious pest of mushrooms. We have seen mites exceedingly abundant in the manure about to be placed in spawn beds. Whether these mush- room mites originate in the „ ... FIG. 91. — A common cheese mite manure used in the beds or (T. longior). (x 60.) not we dare not say. At any rate, manure is often infested with them and some mushroom growers have attempted to fumigate the manure with hydrocyanic acid gas before using it. The life history and transformations of these mites are most remarkable and interesting. All of them lay eggs, which they scatter irregularly over the material upon which they are feeding. The young mites that hatch 282 HOUSEHOLD INSECTS from the eggs have only six legs, but after molting they obtain two more. The young mites may gradually grow, by shedding their skins, into the adult forms, or they may pass through a curious stage, known as the hypopus (Fig. 92). The hypopus is very different in every way from the young mite from which it developed. The body of the hypopus is hard and chitinous and its legs are very short and inefficient for walking. The body on the ventral side near the tip is, however, provided with several sucking disks that serve a very useful pur- pose when the opportunity is presented. There is no mouth opening and there are no distinct mouth- parts. Evidently the crea- ture does not take food in this stage. In fact, the hypopus is a remarkable FIG. 92. — Hypopus of cheese mite, ,"* J j j t 11 much enlarged. body and wonderfully adapted to a peculiar situation. The hard covering of the hypopus protects it from injury and from the influence of fluctuating temperatures, humidity and other influences. In this stage the mites can exist for long periods without food. When favorable conditions return, the hypopus will molt, when, behold ! it has changed to a young mite again which feeds normally and develops to an adult in the regular way. Just what influences induce a young mite to trans- form into a hypopus is not known. It is evidently not INSECTS INJURIOUS TO MEATS 283 a scarcity of food, for it has been shown that hypopi are developed when food is present. It was formerly a source of wonder as to what became of the hordes of mites when they had completely devoured all of a given cheese, for example ; or how an apparently clean storeroom became infested with these tiny creatures. We now know that some of the partly grown mites, either before or at the time the food disappears, transform to hypopi and remain in a half comatose condition awaiting events. As Howard says, "these fortunate survivors, possessing their souls with patience, retire into their shells and fast and wait, and as everything comes to him who waits, some lucky day a mouse or house-fly or some other insect comes that way, and the little mite clings to it and is carried away to some spot — where another cheese or food in some other form is at hand." It is under these circumstances that the sucking disks to which we have already referred perform their useful function, namely, that of fastening the hypopus to its agent of transportation, the mouse or the insect. This is un- doubtedly the manner in which new food supplies and clean storerooms often become infested. These mites are certainly widely distributed over this country and indeed over the world. Considerable con- fusion seems to exist, however, as to the identity of our species with the European forms. It seems certain that the common cheese mite (Tyroglyphus longior) and the flour mite (Tyroglyphus (Aleurobius) farinci) (Fig. 93) both of which are European forms, occur here. These mites increase with great rapidity and in a short time occur in enormous numbers. Flour, for example, may become literally alive with these tiny creatures. A 284 HOUSEHOLD INSECTS correspondent writes to Lintner: "A few days since a neighbor sent us a pan of wheat flour with the request that we examine it. Setting the pan in a quiet place for twenty- four hours, the surface presented a strange appearance — only comparable to that of an ant hill — as though each grain was being separately moved. Slightly disturbing this surface and examining through a common sun-glass of low power it was found to be full of very minute life." Sugars, especially raw sugars, are often found infested to the same extent. Smoked meats, especially hams and shoulders, sometimes swarm with mites to such an extent as to resist all efforts at con- trol and to render them totally unfit for sale. Packing houses and feed mills are occasionally very much troubled with them. It is interesting to know that these mites are some- times checked and practically destroyed by some enemies of their own kind, one or more species of predaceous mites. The predaceous species seem to feed entirely upon their more trouble- some brethren and eventually reduce the latter very greatly in numbers. Howard relates an interesting example of the work of these predaceous mites that FIG. 93. — A cheese mite (T. farinas), (x 80.) INSECTS INJURIOUS TO MEATS 285 came under his observation. A gentleman of Milwaukee sent him some thousands of the flour mites which were found in a bin of wheat in an old elevator. They were so numerous that a quart or more could be gathered every morning below the spout from which they had fallen. An examination showed that at least three species of predaceous mites were present among the flour mites, and were rapidly devouring the latter. In fact, one species was so abundant that there was no hesitation in writing the gentleman that the flour mites would soon be destroyed by the predaceous forms. A week or so later the corre- spondent wrote, "As you say, the parasitic mites have largely destroyed the smaller ones, and I suppose when their food is all gone they will die of starvation." Methods of control. — When once these mites become established in a pantry or storeroom, heroic measures must be taken to exterminate them. The removal of all food-stuffs for a considerable length of time may not avail much when it is recalled that in the hypopus stage the mites can withstand a fast of months and that even the soft, pale, active mites may live for weeks without food. Neither is it any wonder that pantries and store- rooms become infested, considering the ease with which the hypopi are carried about by mice and insects. Infested parts of cheese and hams may be cut out and thrown away. It is often difficult, however, to get all of the mites, for they are so small and so easily escape the sight. Of course, where a few are left they soon reinfest the material. In the case of infested hams, all of the loose powdery material that accumulates on the surface of the meat should be brushed and scraped off as thoroughly as possible. To kill the eggs and any remain- 286 HOUSEHOLD INSECTS ing mites that may have escaped the brushing the meat may be dipped for half a minute in a solution of one part of carbolic acid, ten parts of alcohol, and ninety parts of water. This solution should kill the eggs and mites and not injure the meat. A storeroom or pantry once infested should be thoroughly cleaned and then may be fumigated with sulfur at the rate of 2 pounds to 1000 cubic feet or with hydro- cyanic acid gas at the rate of 1 ounce to 100 cubic feet. If the room is not fumigated, it may be thoroughly sprayed or washed with kerosene oil. The oil should be forced into all of the cracks and crevices where the mites may be in hiding. Prob- ably gasoline would be as effective in killing the mites and would be more FIG. 94. -sugar mite (G. robustus). Peasant to use than kero- (x 50.) sene but more dangerous because of fire. Remarks on the species. — Banks, from the material that he had at hand from the United States, found two species of the genus Glyciphagus. In this genus, the cuticle is more or less granular and the hairs of body plumose or scale-like. The name of the genus indicates that these mites are the true sugar mites and cause the disease of which we have spoken as "grocer's itch." We figure one species G. robustus after Banks (Fig. 94). INSECTS INJURIOUS TO MEATS 287 The species Tyroglyphus farina is the old Aleurobius farince. According to Banks it is not certain that T. siro occurs in this country. He believes that many of the references in literature to T. siro and T. longior refer to a new species T. americanus Banks, which he finds abundant in the collections of the Depart- ment of Agriculture at Washington, D.C., and recorded as occurring on rotten plums, in flaxseed, Wheat, rice, COtton seed, F^. 95. -Tarsi //F, and hairs, A, . ' from T. longior, enlarged. and decaying oranges. The tarsi of T. longior are very long and the hairs of the body are plumose as shown in Fig. 95 after Banks. REFERENCES TO ECONOMIC LITERATURE ON CHEESE MITES 1887. LINTNER, J. A. — A mite infesting smoked meats. Third Kept. Ins. N.Y., p. 130. 1888. CANESTRINI, GIOVANNI. — Prospetto dell' acarofauna Itali- ana, III, pp. 351-418. 1888. RILEY and HOWARD. — Mites infesting an old grain elevator. Insect Life, Vol. 1, p. 51. 1889. LINTNER, J. A. — The cheese mite infesting smoked meats. Fifth Rept. Ins. N.Y., p. 291. 1889. -- The cheese mite infesting flour. Fifth Rept. Ins. N.Y., p. 294. 1890. RILEY and HOWARD. — Mites in a warm-house. Insect Life, Vol. Ill, p. 162. 1896. HOWARD, L. O. — The cheese, ham, and flour mites. Bull. 4, n.s., Bu. Ent., U. S. Dept. Agri., p. 100. 1906. BANKS, NATHAN. — A revision of the Tyroglyphidse of the United States. Tech. Bull. 13, Bu. Ent., U. S. Dept. Agri. 288 HOUSEHOLD INSECTS THE CHEESE AND MEAT SKIPPER Piophila casei It is rather disconcerting, not to say humiliating, for the lady of the house, at the last moment, to find the cheese ordered for a chafing-dish party, full of small, white, lively, and rather disgusting maggots. This is not an uncommon experience by any means. Grocers always Fio. 96. — The parent fly of a cheese skipper. (X 9.) keep their cheese beneath fine-meshed wire netting; but there are many opportunities for the small fly, parent of these skippers, to obtain entrance within and deposit her eggs. The insect that lays these eggs is a small, shining-black fly scarcely one-half the size of a house-fly (Fig. 96). The eggs hatch into small white slender maggots that become about one-third of an inch in length. These maggots possess remarkable powers of leaping and on this account are called "skippers." They have no legs, yet by bring- ing the two ends of the body together and suddenly re- INSECTS INJURIOUS TO MEATS 289 leasing them like a spring they are thrown considerable distances, four or five inches. The cheese skipper was probably imported from Europe. It is now widely distributed over the United States. In fact, it is a cosmopolitan pest. C. V. Riley in 1880 showed that the same fly laid its eggs on cured meats, where they hatched and the " skippers " infested the meats. Thus it has also become known as the "meat skipper." In fact, it probably causes much more loss to the large meat packing establishments than it does to cheese making factories. Miss Murtfeldt quotes from a letter from a packing-house company regarding this insect as follows : " We wish to know what it is and especially at what period in its life it can best be fought. It entails an enormous loss upon all of our packing-house companies." The fly infests hams and shoulders, and other smoked parts of the carcass. Apparently, it is not much attracted to fresh meats or to those simply salted. Moreover, it seems attracted to pork more than to beef. Even when a ham of beef and of pork hang side by side, it prefers the pork. In cheese manufactories there is evidently less damage than formerly. The cheese storerooms are often darkened and the cheeses turned and rubbed every morning with grease. The skippers are notorious for their habit of infesting the better and richer cheeses. One can be sure that a "skippery" cheese is a good one but not good because of the presence of the skippers. It is not to be supposed that the skippers actually improve the cheese, although there is an old English custom of placing cheese under the drip of a beer keg to attract the insect and encourage its development. Miss M. E. Murtfeldt made a series of observations 290 HOUSEHOLD INSECTS on the life history of the cheese skipper in the summer of 1892. She found that the egg was pearly white, slightly curved, and one-twenty-fifth of an inch in length. The eggs may be deposited in more or less compact clusters of five to fifteen or they may be laid singly in folds of the wrapping FIG. 97. — Cheese skip- cloth. The eggs hatch in thirty-six per^maggotofP.casei. nours an(j tiie minute slender larvse go at once in search of food. The larva, or "skipper," is cylindrical, tapers gradually toward the anterior end but is truncate at the posterior end (Fig. 97). Projecting from the posterior end are two horny stig- mata and a pair of fleshy filaments. The maggots attain their full growth in seven to eight days, becoming about one-third of an inch long. While feed- ing, if there is an abundant supply of food, the larvse do not move about much. When they become full-grown, however, each one crawls to a crack or crevice in the fold of the wrapper and there contracts and changes to a pupa (Fig. 98). The pupal stage occupies about ten days. Thus in August the life cycle would be passed in three FlG weeks. Kellogg also studied the life history of this insect during February and March of the same year. He found at this time of year that the egg stage occupied about four days and that the larvse were about two weeks in completing their growth. The pupal stage — Pupa of cheese skipper, enlarged. INSECTS INJURIOUS TO MEATS 291 occupied about one week. In this case then the life cycle occupied between three and four weeks. Probably the stages were prolonged by the lower temperature. The flies are certainly more active and more injurious during the hottest part of summer. H. F. Kessler has also made careful observations on the life history of this insect in Europe. He found that the average time for the production of a generation of the flies was between four and five weeks and that there were two or three generations during the season. He found that the insect passed the winter as puparia and that the flies emerged the following spring in May. Other observers say that the adult flies hide in secluded nooks and live over the winter. Methods of control. — Cheeses, when made at home, should be carefully examined every day, especially in the months of August and September. The checks and cracks should be kept filled with particles of cheese that have been crushed smooth in order to work into the crevices nicely. The bandages should be tight about the edges and should fit smoothly. By greasing the outsides of the cheeses and by turning them and examining them every day they can be kept free from skippers. Infested portions of cheeses may be cut out and thrown away. When pieces of infested cheese are obtained from the grocer, they may be returned. Hams are usually found to be infested only in certain portions and the remaining portions usually remain sweet and wholesome. Fortunately, the presence of the skippers does not induce decay and putrescence. The infested parts of the meat may then be cut out and thrown away while the remainder may be safely used for food. 292 HOUSEHOLD INSECTS Pantries or storerooms once infested should be thor- oughly cleaned, fumigated with sulfur, and washed with ordinary kerosene oil. Special pains should be taken to clean out all the cracks and wash them with the oil because the puparia of the flies may often lurk in such places. The flies may be kept out of rooms or receptacles by using wire screen having 24 meshes to the inch. If these pests are troublesome, the storeroom should be thoroughly screened so that the flies cannot gain entrance. REFERENCES TO ECONOMIC LITERATURE ON THE CHEESE SKIPPER 1870. WILLARD, A. — The cheese-fly. American Entomologist, Vol. 2, p. 78. 1880. RILEY, C. V. — Skippers injuring smoked hams. American Entomologist, Vol. 3, p. 23. 1892. KELLOGG, V. L. — The ham fly. Transac. Kansas Acad. of Science, Vol. XIII, p. 114. 1893. MURTFELDT, Mary E. — The cheese or meat skipper. Insect Life, Vol. 6, p. 170. 1896. HOWARD, L. O. — The cheese skipper or ham skipper. Bull. 4, Bu. Ent, U. S. Dept. Agri., p. 102. 1897. LINTNER, J. A..—Piophila casei. Twelfth Rept. N.Y. Ins., p. 229. See Lintner's Twelfth Report for further references. THE CIGARETTE BEETLE Lasioderma serricorne_ -A&