INDEX 



729 



Smilisca, 519. 



Snail, 253-257. 



Snakes, 527, 536, 538-539, 557-569 ; 



Congo, 514; horsehair, 179. 

 Snipe, 590, 607. 

 Sole, 469. 

 Solen, 262. 

 Solenodontidce, 650. 

 Solifugce, 382. 

 Somatic, cells, 46, 47, 73 ; mesoderm, 



57- 



Si unite, 90. 



Songs of birds, 621. 



Sorex, 042, 649, 650; Soricida, 649. 



Sparrow, 593, 615. 



Spatangus, 190. 



Species, 22, 23. 



Spelerpes, 511, 517. 



Spermatheca, 226, 227 (see reproductive 



system). 

 Spermatid, 81. 

 Spermatocytes, 81. 

 Spermatogenesis, 81-82. 

 Spermatogonia, 81. 

 Spermatozoa, 47, 75, 81. 

 Sph&rodactylus, 537, 552. 

 Spharophyra, 65. 

 Sphargis, 544. 

 Sphegida, 364, 367. 

 Sphenethmoid, 493, 494. 

 Spheniscus, 589 ; Sphcnisciformes, 589, 



598. 



Sphenodon, 536, 546, 695. 

 SphingidcE, 352 ; Sphinx, 335. 

 Sphyratnira, 161. 

 Sphyrna, 429. 



Spicules, of sponges, 93, 95, 99, 191. 

 Spiders, 24, 371-377. 

 Spilogale, 655. 

 Spinal cord, 408, 503-504 (sec nervous 



system). 

 Spinal nerves, 503, 504 (see nervous 



system). 

 Spines, of echinoderms, 190, 201, 292 ; 



haemal, 436; of perch, 435. 

 Spinneret, 373, 376. 

 Spiracle, insects, 319, 320 ; Squalus, 424 ; 



tadpole, 510. 



Spiral valve, 418, 423, 425. 

 Spireme, 15. 

 Spirobolus, 310. 

 Spirorbis, 236. 



Spiroslomum, 63. 



Spittle insects, 346. 



Splanchnic mesoderm, 507. 



Spleen, 451; frog, 492 ; perch, 438; ver- 

 tebrates, 401, 402. 



Sponges, 23, 92-107. 



Spongilla, 98, 98, 100. 



Spoiifjin, (jo, 101. 



Spongoblasts, 100. 



Spontaneous generation, 12. 



Spores, 48, 49. 



Sporoblast, 49, 50. 



Sporocyst. 159, 160. 



Sporozoa, 27, 48-53. 



Sporozoitcs. 49, 50. 



Sporulation, 33. 



Springtails, 337, 338. 



Squall, 428. 



Sqiidlus, 422-428. 



Squamata, 527, 536, 550-569, 694, 695 



Squamosal, 493, 494. 



Squid, 264-267. 



Squilla, 298, 299, 301. 



Squirrel, 643, 658, 659. 



Stapliyliniilcc, 361. 



Starfish, 24, 189, 190-199. 



Starling, 591. 



Statocyst, 286 (see sense organs). 



Statolith, 286 (see sense organs). 



Slauromcditscr, 132, 133. 



Staurotypus, 535. 



Slegoccphalia, 525, 526, 694, 695. 



Stegomyia, 356. 



Stegosaurus, 572, 573. 



Stenopus, 297. 



Stcntor, 64. 



St en-oral pocket, 373, 374. 



Strn-ulrpis, 466. 



Strriintturriis, 535. 



Sternum, 276, 372, 495, 496 (see skele- 

 ton). 



Stickleback, 444, 464. 



Stigma, 42, 43. 



Stigmata, 378, 379. 



Stilt, 607. 



Sting, 317. 



Stolonifera, 139, 140. 



Stumac li. cardiac, 480; pyloric, 481 (see 

 iligestivc system). 



Stomato-gastric ganglion, 321. 



Stomatopoda, 297, 298. 



Slomias, 473. 



