INDEX. 



719 



Solitaire, 547 



Somateria mollissima, 543 



Somite, 266 



Sores platyrhinus, 587 



Sounds produced by insects, 349 



Sounds, fishes', 442 



Spalax, 586 



Sparrow, 555 



Spatangus, 124 



Specialization, 6 



Species, origin of, 672 



variation of, 10, 672, 673 

 Spermaceti, 593 



Spermatozoa, formation of, 644 

 Sphferodorum, 231 

 Spliargis coriacea, 510 

 Spheuodon, 511 

 Spheotyto cunicularia, 549 

 Sphex ichneumonea, 363 

 Sphinx, 359 

 Spiders, 342 

 Spirialis Gouldii, 239 

 Spirula Peronii, 261 

 Sphyrna zygyena, 421 

 Spirorbis, 237 

 Sponges, 42 



silicious, 47 



useful, 49 

 Spongia adriatica, 49 



equina, 49 



gossypina, 49 



tubulifera, 49 

 Spongilla. 47 

 Spoonbill fish, 428 

 Sporocyst of Nematodes, 151 

 Spring-tails, 344 

 Squalus Americanus, 420 

 Squamella oblonga, 176 

 Squid, anatomy of, 273 

 fiquilla, 292 

 Squirrels, flying, 583 

 Star-fish, 96, 109, 111 



anatomy of, 96 

 Star worm, 221 



Statoblast, 187 

 Stegocephala, 482, 488 

 Steller's manatee, 596 

 Stentor polymorphus, 36 

 Sternum of insects, 309 

 Stick insect, 677 

 Stickleback, 456 

 Still, 546 

 Sting rays, 424 

 Stomapoda, 292, 305 

 Stone lilies, 101 

 Strobila of Hydrozoa, 66 

 Strobila of Planarians, 144 



tape-worms, 156 

 Strobilation in worms, 144, 145 

 Struggle for existence, 673 

 Strut hio camelus, 539 

 Sturgeon, embryology of, 427 

 Sturgeon, 427 

 Stygicola dentata, 459 

 Stylaster, 58 

 Styliola vitrea, 238 

 Stylochus elliptic.a, 143 

 Stylocordyla, 48 

 Stylops, 353, 354 

 Sucker, 453, 454 

 Suctoria, 40 

 Sun-fish, fresh water, 455 



banded, 455 



spotted, 456 



salt- water, 462 

 Swimming, in fishes, 444 

 Sycandra, 44 

 Sycon ciliatum, 45 

 Syllis, 235 



Symmetry, bilateral, in cteno- 

 phores, 92, 93 



echinoderms, 120 

 Symphyla, 344 

 Syuapta, 134, 135 

 Syncarida, 272 

 Syngnathus peckianus, 461 

 Synthetic types, 483, 679 

 Syrinx, 526, 552 



