402 



Index 



70; transformation, 117-18; 



scales, 313-14; uses ot, 342. 

 Scarabjeida;, 215-16, 360. 

 Scavengers, 304-5. 

 Scent-glands, 69. 

 Sclerites, 5 ; of head, 6; of neck, 19 ; 



of thorax, 21 ; of abdomen, 30. 

 Scoliidx, 277-8. 

 Scolopendrella, 364-5. 

 Scolytidas, 224. 

 Scorpion-flies, 205. 

 Scorpions compared with insects, 



367-9, 372. 

 Scutum and scutellum, 21. 

 Scydmsenidz, 209. 

 Seashore insects, 294-5. 

 Secondary epoch, insects of, 353, 



355> 360-3. 



Segmentation nucleus, 86. 



Segmentation of egg-cell, 89 ; of 

 embryo, 93-4. 



Segments, 2 ; of head, 8 ; of 

 thorax, 20-1 ; of leg, 22-4; of 

 abdomen, 30-1, 78-9 ; homo- 

 logy of, 372. 



Selection, natural, 141-7; sexual, 



3^5-6. 



SericostomatidaE„227. 



Serosa, 91-3, 96. 



Sesiidse, 234. 



Sessiliventres, 270-2. 



Sexual differences and modifica- 

 tions, 324-8 ; reproduction, 73 ; 

 selection, 325-6. 



Shield-bugs, 187. 



Shin, 23. 



Sialids, 203, 360. 



Silk-glands, 106-7. 



Silk-worm, 106, 245, 342. 



Silphida;, 210. 



Simple eyes, 40. 



Simuliidse, 124, 257. 



Siphonaptera, 253. 



Siricidse, 271. 



Skin, structure of, 5. 



Slaves, 336-7. 



Small intestine, 64. 



Smell, 48. 



SmynthuridsE, 167. 



Snake-flies, 118, 203. 



Soldiers, 338. 



Solitary wasps and bees, 279, 



330-1. 

 Sounds made by insects, 47, 175-6, 



J 94) 326. 

 Spermatheca, 75, 86. 

 Spermatids, 80. 

 Spermato-blasts, 80 ; -cysts, 80 ; 



-cytes, 80, 86 ; -phores, 82 ; 



-spores, 80. 

 Spermatozoa, 73, 80, 86. 

 Sperm cells, 73, 80, 86, 99 ; ducts, 



81 ; vesicles, 79-81. 

 SphegidjE, 278-9 

 Sphingids, 242. 

 Spiders, compared with insects, 2, 



367-9- 

 Spinneret, 106-7. 

 Spiracles, 59, 109, 121. 289-94. 

 Spittle-glands, 67, 96. 

 Springtails, 165-8 ; absence of 



wings, 29 ; kidney-tubes, 71 ; 



ovaries, 75 ; embryo, 93 ; in 



caves, 286-8 ; relationships, 



346-7- 



Stag-beetles, 215. 



Staphylinids, 209, 297. 



Stem-boring insects, 302-3. 



Sternum, 21, 30. 



Stick-insects, 174-5, 317. 



Stings, 69-70, 77-8, 



Stipes, I 3. 



Stomach, 63. 



Stomato-gastric nerves, 34. 



Stomodxum, 64, 96. 



Stone-flies, 182-3 ; wings, 28 ; 

 cercopods,3i ; gills, 61 ; kidney- 

 tubes, 71 ; larvs, 106-112. 



Stratiomyids, 259. 



Strepsiptera, 224. 



Struggle for existence, 141. 



Stylets, 31, 78-9, 94, 372. 



Stylopids, 224-5. 



Sub-classes, 1 64. 



Sub-costal nervures, 27, 228, 252. 



Sub-family, 155. 



