ANIMAL LIFE 



Structure, 63; differentiation of, 64. 



Struggle for existence, 116. 



Sty lops parasitizing Polistes (illus.), 

 192. 



Sub-species, definition of, 282. 



Surroundings, adaptations con- 

 cerned with, 143. 



Swallow-tail butterfly, chrysalid 

 of (illus.), 205. 



Sword-fish, metamorphosis of (il- 

 lus.), 99. 



Symbiosis, 172, 175. 



Syngamus trachealis (illus.), 60. 



Systematic zoology, 64. 



Tactile organs, 226. 



Tactile papilla of skin of man (il- 

 lus.), 227. 



Tadpole, 94. 



Tcenia, solium (illus.), 183. 



Tailor-bird, nest of (illus.), 268. 



Tape-worm (illus.), 183. 



Taste buds of calf (illus.), 229. 



Taste organs, 228. 



Taste, sense of, 228. 



Temperature a barrier to distribu- 

 tion, 290 ; a condition of animal 

 life, 108. 



Tentacle, 37. 



Termite, 158, (illus.), 159. 



Terrifying appearances, 212. 



Thalessa lunator (illus.), 191. 



Toad, egg of (illus.), 79; horned 

 (illus.), 131 ; metamorphosis of, 

 94, (illus.), 95. 



Torpedo (illus.), 135. 



Tortoise, embryonic stages of (il- 

 lus.), 87. 



Touch, sense of, 226. 



Trap-door spider nest (illus.), 261. 



Tree-hoppers mimicking leaf-cut- 

 ting ant (illus.), 220. 



Tree-toad (illus.), 145. 



Tremex columba (illus.), 191. 



Trichechus latirostris (illus.), 277. 



Trichina spiralis (illus.), 184. 



Tripoli, 19. 



Trochilus rufus, nest of (illus.), 



265, 266. 

 Trout, rainbow, head of (illus.), 



145. 



Two Ocean Pass (illus.), 287. 

 Tunicate (illus.), 194. 

 Turret-spider, nest of (illus.), 262. 

 Typhlichthys subterraneus (illus.), 



282. 



Uncinaria, killing fur-seal pups 



(illus.), 186. 



Uria lomvia arra (illus.), 165. 

 Urolophus goodei (illus.), 133. 



Vacuole, 10; contractile, 10. 



Variety, definition of, 282. 



Vedalia and Icerya, 121. 



Vertebrates, early stages in devel- 

 opment of (illus.), 87 ; nest-mak- 

 ing habits of, 264 ; parasitic, 193. 



Vespa (illus.), 162 ; nest of (illus.), 

 163. 



Vestigial organs, 147. 



Viceroy butterfly mimicking Mon- 

 arch butterfly (illus.), 219. 



Voice, 236. 



Volvocinse, 24. 



Volvox, 28. 



Volvox globator (illus.), 29. 



Volvox minor (illus.), 29. 



Vorticella, 12. 



Vorticella microtoma (illus.), 12. 



Walking-stick insect (illus.), 209. 

 Warning colors, 212. 

 Walrus, Atlantic (illus.), 298. 



