540 



INDEX 



Shame, in animals, 492. 



Sharks, 278. 



Sheep, 384. 



Sheep tick, 215, 227. 



Shellac, source of, 206. 



Shellfish, 228. 



Shell gland, of Daphnia, 152. 



Shelly loop, of Brachiopoda, 132. 



Shipworm, 249. 



Shore fauna, 447. 



Shoulder blade, of Mammalia, 358. 



Shovel-nosed sturgeons, 285. 



Shrews, 393. 



Shrikes, 355. 



Shrimp, 168, 169. 



Siderone, 464. 



Siliceous sponges, 450. 



Silicispongiee, 60. 



Silkworm moths, 215. 



Silurian fossils, 419. 



Silurian period, 13, 443. 



Silver pheasants, 350. 



Simla satyrus, 410; S. troglodites, 411. 



Simple intelligence, 487. 



Simple reflex action, 482. 



Singing birds, 355. 



Sinistral shells, 234. 



Sinus rhomboidalis, of pigeon, 333. 



Sinus venosus, of dogfish, 277; of frog, 



301 ; of lamprey, 273. 

 Siphon, of Lamellibranchia, 243-245; of 



Prosobranchia, 234. 

 Siphonaptera, 226, 227. 

 Siphoniata, 246, 248. 

 Siphonoglyph, 73. 

 Siphonophora, 69. 

 Siphonophores, 447. 

 Siphuncle, 254, 

 Siredon, 304. 

 Sirenia, 372, 433, 448. 



n laceriina, 302. 

 Six-banded armadillo, 371. 

 Skates, 279. 

 Skeleton, of birds, 331, 332; of Mammalia, 



357-359- 

 Skippers, 212, 213, 227. 

 Skull, of Mammalia, 357. 

 Skunks, 399. 

 Slime-moulds, 13. 

 Slipper limpets, 234, 236. 

 Sloths, 369, 370, 454. 



gs, 231, 241. 

 Smallest vertebrate, 297. 

 Snails, 231. 

 Snakes, 315. 

 Snapping turtle, 324. 

 Snipes, 351. 

 Snow bunting, 353. 

 Snowflake, 353. 



Social behavior, 491. 



Social wasps, 224. 



Soft-shelled turtle, 323. 



Soldiers, among ants, 224 ; of termites, 200, 

 201. 



Sole, 293. 



Solenogastres, 229. 



Solitaire, 352. 



Solitary digging wasps, 224. 



Solpugida, 180. 



Somatic cells, influence on germ-cells, 477. 



Somatic mesoderm, 51. 



Somite, definition of, 134. 



Song sparrow, 354. 



Songsters, 355. 



South American opossums, 366. 



South American ostriches, 454. 



Sow bugs, 163. 



Spanish flies, 220. 



Spanish mackerel, 292. 



Sparrows, 354, 355. 



Spat, 246. 



Spathegaster taschenbergi, 223. 



Spayed animals, 478. 



Special creation, 458, 499, 501. 



Species, 9; origin of, 458. 



Speckled turtle, 324. 



Specter, 406. 



Spencer, 508. 



Sperm animalcules, 498. 



Sperm sac, of dogfish, 277. 



Sperm whale, 375. 



Spermaceti, 375. 



Spermatidia, 130. 



Spermatists, 498. 



Spermatophore, of Cephalopoda, 253. 



Spermatozoa, 52 ; discovery of, 498 ; func- 

 tion first discovered, 507. 



Sphaerogastres, 177. 



Sphenethmoid, of frog, 300. 



Spheno don punctata, 321. 



Spider crabs, 450. 



Spider monkeys, 408, 409. 



Spiders, 182, 432. 



Spilotes couperi, 318. 



Spinal canal, of lamprey, 273. 



Spinal cord, of Amphioxus, 269; of dogfish, 

 277 ; of frog, 301 ; of lamprey, 273 ; of 

 pigeon, 333. 



Spinnerets, 183. 



Spinning glands, of spiders, 183. 



Spiny ant-eaters, 363. 



Spiracles, of Cetacea, 373; of dogfish, 275. 

 277 ; of Selachii, 278, 280 ; of sturgeons, 

 284. 



Spiral valve, of Dipnoi, 297 ; of dogfish, 

 277; of Elasmobranchii, 276; of Ganoi- 

 dei, 284; of Holocephali, 282; of Tele- 

 ostei, 287 ; of Teleostomi, 283. 



