INDEX 



411 



Trachea of fly, 63. 



Tracheata, 387. 



Trachina, 152, 153. 



Trachomedusae, 221. 



Trap-door spiders, 80. 



Tree-hoppers, 14. 



Trematoda, 385. 



Trepangs, economic importance of, 



202. 



Tree-sparrow, 285. 

 Tree-toad, 265. 

 Triangular crabs, 123. 

 Triforidae, 177. 

 Trilobites, 130. 

 Trionychidae, 274. 

 Trionyx, 275. 

 Trochidae, 175. 

 Trochilus, 302. 

 Troglodytidae, 287, 316. 

 Troglodytes, 288. 

 T routs, 233, 253. 

 True bugs, 12. 

 True wasps 83. 

 Tsetse-fly, 64. 

 Tube-forming worms, 102. 

 Tube-weavers, 88, 96. 

 Tubifex, 136, 144. 

 Tubificidae, 144. 

 Tubitelariae, 88, 96. . 

 Tubularia, 208. 

 Tubularian hydroid, 210. 

 Tubularidaj, 208, 221. 

 Tumble-bugs, 50, 57. 

 Tunicata, 218, 251. 

 Tunnel-weavers, 85, 95. 

 Turbellaria, 385. 

 Turdidge, 285, 315, 316. 

 Turdus, 286. 

 Turkey-buzzard, 299. 

 Turkeys, 304; wild, 305. 

 Turtles, 273; range of , 274. 

 Tussock moth, 28". 

 Twin-spotted sphinx, 23. 

 Tyrannidae, 295, 315. 

 Tyranuus, 296. 



Unau, 324. 



Ungulata, 325, 331; even-toed, 326; 

 odd-toed, 327. 



Unio, 178, 191. 



Unionidas, 179, 180, 191. 



Urodela, 255, 266 ; development of, 261. 



Urosalpiux, 169, 175. 



Varanidae, 269. 

 Variations in Helix, 1(55. 

 Veneridae, 180, 183, 190. 

 Venus, 183. 

 Vermetidae, 174. 

 Vertebrates, ancestry of, 248. 

 Vespa, 34, 35. 

 Vesper sparrow, 285. 

 Vesperidae, 43. 

 Vespidae, 33. 

 Vireo, 288, 290. 

 Vireonidae, 288, 316, 317. 

 Volvox, 226, 227. 

 Von Baer's law, 336. 

 Vorticella, 225, 229. 

 Vultures, 298, 299. 



W 



Walking-sticks, 7, 15. 



Wall-eyed pike, 235. 



Walruses, 329. 



Wandering spiders, 88. 



Warblers, 285. 



Wasps, 30, 33, 43; social, 33. 



Water-dog, 257.. 



Water moccasin, 279. 



Water scavengers, 60. 



Water snakes. 271. 



Water strider, 12. 



Weasels, 328. 



Weevils, 57. 



Whales, 324; feeding habits of. 325. 



Whippoorwill, 303. 



Whirligig, 60. 



White ants, 11. 



White-breasted nuthatch, 287. 



Whitefishes, 234, 253. 



White-lined horse-fly, 6(5. 



W T hite-throated sparrow, 285. 



Wingless birds, 307. 



Wingless cockroach, 8. 



AVood-borers, 41. 



