INDEX 



469 



Horse-flies, 405 



Hou8e-flies and disease, 438 



Hybrids, 122-126 



Hydrometra, 281-282 



Hymenoptera, wing-coupling, 58 ; 

 sex-determination, 138-140 ; 

 larvae, 179 ; family life, 

 213-214, 215-217 ; societies, 

 222-253 ; characters, 317 ; 

 sub-orders and families, 318- 

 320 ; relationships, 334 ; 

 geological history, 342-343 ; 

 adaptation to flowers, 394- 



395 

 Hypoderma, egg-laying, 109, 400 ; 

 larval wandeiing, 109-110; 

 relations with cattle, 399- 



405 



Hyponomeuta larval communities 

 and webs 214-215 ; winter- 

 ing, 302 



Hypopharynx, 19 



Ileum, 31 



Imaginal discs, 173-174 



Imported enemies of pests, 423-424 



Individuality of insect societies, 

 260-261 



Inhibitors of germinal factors, 352 



Injuries to plant-tissues, 393-394 



Inquilines, bees and wasps, 233-236; 

 gall-flies, 387 



Insecta, general form, I ; characters, 

 13-14 ; synopsis of orders, 

 309-317 ; extinct groups, 

 336-345 ; relationship to 

 other Arthropoda, 346-349 



Insectivorous plants, 395-396 



Instinct, 95, 102-103 



Intelligence, 103-106 



Intersexes, 133-135 



Intestine, 30-32 



Isolation, 377-378 



Isopoda, 349 



Isoptera, 311 



Isotoma tenella, 11 1 



Ithomiinae, 371-372 



Jaws, 5, 17-23, 61-67, 329-330 



Jugum, 58-59 



Jurassic fossils, 339, 341 



Labium, of earwig, 19 ; of tabanid, 



21 ; of bug, 21 ; of house- 

 fly, 23 



Labrum, of earwig, 17 ; of tabanid 

 and bug, 21 



Lac-insect, 444 



Lamarckian factor, 357, 362-365 



Larva, of Psylla, 165-166 ; of cicad, 

 168 ; of moth, 170 ; of 

 beetles, 177-179 ; of Hy- 

 menoptera, 179, 182 ; of 

 Diptera, 179-183 ; diver- 

 gence from adult, 184, 189- 

 190 ; campodeiform, cruci- 

 form and vermiform, 186 



Larviparous insects, 195 



Lasiocampa rubi, 302-303 



Lasioderma serricorne, 426 



Lasius and guests, 251-252 



Leaf-cutting ants, 239 



Leaping, 53 



Legs, 2, 47, 50-53 



Lepidoptera, jaws, 23-24 ; life- 

 history, 11-12, 170-174; 

 wing-couplings, 58-60 ; pair- 

 ing, 201-202, 203-206 ; 

 gregarious caterpillars, 214 ; 

 body-form, 270 ; characters, 

 315-316; relationships, 33 5- 

 336 ; geological history, 341 ; 

 value of wing-patterns, 369- 

 371 ; adaptation to flowers, 



394-395 



Leptinotarsa, modifications, 362 

 1 Liassic fossils, 339, 342 

 I Lice, 164, 312, 406-408, 437 

 I Limbs, 2, 5, 347-348 

 I Lipeurus, on ratite birds, 407 



Lipoptera hirundinis, 405 



Locusts, body-form, 270 ; plague?, 



445 

 Looper caterpillars, 272-273, 369 

 Lucilia, 112, 399 

 Lycaenidae, sexual differences, 201 ; 



caterpillars and ants, 252 ; 



variation, 356 

 Lygus pabulinus, jaw-muscles, 65- 



67 



Machilis, 327 



Maggots, reaction to light, 9: 



structure, 180-183 

 Malaria and mosquitoes, 431-434 

 Mallophaga, 164, 312, 406-408 

 Malpighian tubes, 7, 38-39 



