494 



INDEX 



389; grasshopper, 380; vesper, 374, 



375- 



spawn, 276, 295. 



species, 104. 



spermatozoa, 263 ; of Hydra, 203 ; of 

 mussel, 151 (see reproduction). 



spicules, of sponge, 214, 215. 



spider, 7, m-ii8; aerial, 115, 116; 

 anatomy of, 113 ; bites of, 118; crab, 

 116; house, 116; jumping, 116; red, 

 126; reproduction of, 114 ; respiration 

 in, 114; sense organs of, 114; spinning 

 organs of, 113; tarantula, 117; trap- 

 door, 117; water, 116; webs of, ui- 



113- 



spinal cord, 258, 259, 260. 



spinnerets, of spider, 115. 



spiracle, of frog, 267. 



spirochaets, 228, 229. 



spleen, of frog, 253. 



sponges, 7, 211-217: bath, 212, 216; 

 classification of, 217; collecting, 215- 

 216; colonial, 210; f resh- water, 210 ; 

 relations to other organisms, 215; re- 

 production of, 212; simple, 2H-212; 

 solitary, 212; spicules of, 214, 215; 

 spongin of, 214, 215. 



spongin, 214, 215. 



spores, of malaria parasite, 226. 



sporocyst, 187. 



Sporozoa, 227, 233. 



sporulation, 223, 224. 



squid, 164, 165. 



squirrels, 388, 414 ; ground, 431 ; flying, 

 432 ; tree, 430. 



stapes, 409. 



starfish, 7, 193-194 ; relation of, to oyster, 



155- 



statocyst, of snail, 160. 

 Stentor, 225. 

 sternum, 255. 



sting, of scorpion, 118, 119. 

 stinging cells, 200, 201. 

 stomach, of crayfish, 132, 134; of frog, 



247; of grasshopper, 12, 14; of mussel, 



147, 151 ; sucking, of moth, 26. 

 struggle for existence, 4. 

 sturgeon, 279, 280. 

 sucker, 280, 281 ; of liver fluke, 186. 

 sunfish, 287. 

 swallow, 380 ; bank, 344, 355 ; cliff, 370, 



371. 



swan, 366, 381. 



swift, chimney, 369, 370, 374, 387. 



swimmeret, of crayfish, 132, 135. 



Sycotypus, 163, 164. 



symmetry, 192. 



sympathetic nervous system, 12, 17-18, 



260. 



Syngamus, 181, 182. 

 Synura, 231. 

 syphilis, germ of, 229. 



Tania, 188. 



tail, of bird, 339. 



tapeworm, 7, 188-191. 



tapir, 418, 441. 



tarantula, 117. 



tarpon, 286, 287. 



tarsus, of grasshopper, 1 1 . 



taste, in fish, 275; in insects, 17; in 



mammals, 410 (see sense organs), 

 teeth, of frog, 246 ; of mammals, 404- 



406; milk, 405. 

 Teleostomi, 279-284. 

 tendon, 256. 



tentacles, of Hydra, 199, 200; of jelly- 

 fish, 207; of snail, 159, 160. 

 tern, 352, 357, 365. 

 terrapin, 313, 315, 333. 

 terrestrial habitat, 2. 

 testes, of frog, 262, 263 ; of grasshopper, 



12 ; of Hydra, 199, 200 ; of mammals, 



410; of mussel, 147, 151. 

 thorax, 10. 

 threadworms, 7. 

 thrush, 375. 

 thymus gland, 254. 

 thyroid gland, 254. 

 tibia, of grasshopper, n. 

 tibiofibula, 256. 

 tick, 119; fowl, 124; sheep, 53-54 



spotted fever, 126; Texas fever, 121- 



122. 



tiger, 429. 

 tissues, 241-242. 



toad, 106, 305-307; horned, 319, 320. 

 tongue, of frog, 246 ; of lamprey eel, 268, 



269. 



tortoise, 315, 316. 

 tortoise shell, 317, 333. 

 touch, in fish, 275; in insects, 17; in 



mammals, 409 (see sense organs), 

 trachea, of mammals, 406. 



