INDEX. 



Kirenidre, 436. 



,S7a, 5i6. 



Sivatherium, 535, 645, 649. 



Slaters, 245. 



Slimonia, 253. 



Sloth, 538, 539. 



Snakes, 445, 443, 453, 454, 456, 457. 



Solarium, 34 J. 



Solaster, 167. 



Solecurtus, 328. 



SoZera, 328. 



Solenidce, 327, 323. 



Solidungula, 580, 584, 641. 



Solipedia (see Solidungula). 



Solitaire. 519. 



Solpugidce, 261. 



Somateria, 506. 



Somatic cavity, of CceJenterata, 86 ; of 

 Hydrozoa, 88 ; of Hydra, 91 ; of Actino- 

 zoa. 125. 



Somatocyst, 103, 104. 



Somite, 218 ; of Crustacea, 220 ; of .4>ac7i- 

 mda, 254. 



Sorex, 628. 



Soricidce, 627. 



Soroidea, 63. 



Spalacotherium, 639. 



Spar sis pongia, 75. 



Spatangidte, 163. 



Spatiformes, 163. 



Spatularia, 416. 



Species, definition of, 23 ; origin of, 4). 



Spermatophores, 347. 



Sperm-whale, 577. 



Sphcerogastra, 262. 



Sphceroma, 244. 



Rphceronec ide, 106. 



Sphcerozoum, 68. 



Sphagodus, 429. 



Xphargis, 451. 



Spheniscidce, 502. 



Spheniscus, 503. 



Spicula, of Sponges, 70, 73 ; of R>tdlo- 

 laria, 67, 6 ; of ^dmozoct, 132, 137. 



Spider-monkey, 633. 



Spiders, 254, 235, 257, 262. 



Spinax, 419. 



p niferites,, 75. 



Spinnerets of Spiders, 263 ; of Caterpillars, 

 286. 



Sp.:o, 87. 



Spirialis, 343. 



Spirifer, 316. 



Spirifendx, 316, 319. 



Spiriferina, 31*. 



Spirorbis, 212, 216. 



Spirula, 349, 352, 358. 



Spirulidce, 352, 3)8. 



Spirulirostra, 358. 



SpondyJus, 327. 



Spongida, 69 ; skeleton of, 70, 73 ; sar- 

 coids of; 70, 73 ; aquiferous system of, 

 71 j reproduction of, 72; classification 

 of, 73; distribution of, in space, 74,; 

 in time, 75 ; affinities of, t'6. ; individu- 

 ality of, 76. 



Spongilla, 54, 74 ; reproduction of, 74 ; 

 sarcoids of, i&. 



Spoon-bill, 510. 



Spoon-worm, 203. 



Spores, of Sponges, 73. 



Sporosac, of C'orynid : .i, 94, 95. 



Spring-tails, 270, 273. 



SqualidcB, 422. 



Squalodon, 530. 



Squamae, of Aphrodite, 214. 



Squamata (Reptilia), 446. 



Squamulina, 64. 



Squids, 344, 350. 



Squilla, 245. 



Squirrel, 622. 



Squirrel Monkey, 633. 



Staggers, of Sheep, i&9. 



St'igonolepis, 470. 



Star-nosed Mole, 627. 



Statoblasts, 29, 305. 



Stauria, 151. 



Stauridfe, 151, 153. 



Stauridia, 96. 



Steatoritiis, 528. 



Strganddictyum, 75. 



Steganophthalmata (Medusa), 110, 114, 

 115, 120. 



Stem-muscle, of Vorticdla, 79. 



Stemmata (see Ocelli). 



Stenaster, 182. 



Steneosaurus, 471. 



Stcnostomata, 146. 



Stentor, 10, 82. 



Stephanoceros. 198, 201. 



Stephanomiadce, 109. 



Sterelmintha, 192. 



Stereognathus, 639, 640. 



Sternaspis, 204. 



Sternum, of Crustacea, 222 ; of Aruch- 

 nida, 255 ; of Chelonia, 451 ; of ^4ves, 

 486; of Mammalia, 540. 



Stichostega, 63. 



Stigmata, of Physophorid t>, 107 ; of 

 Leeches, 208 ; of AracJinida, 257 ;* of 

 Insecta, 273. 



Stolons, of Foraminffera, 61 ; of com- 

 posite -4c<inozoa, 135 ; of social Tuni- 

 cata, 3lo. 



Stomapoda, 226 ; characters of, 245 ; de- 

 velopment of, i&. ; distribution of, iu 

 time, 254. 



Stomatodendra, 119. 



Stork, SOS, 510. ^X' 



Strepsiceros, 596. 



Strepsilas, 510. 



Strepsiptera, 2^9, 290. 



Mrepsirhina, 630, 631. 



Streptnspondylus, 471. 



Strigidte, 529. 



Stringocephalus, 316. 



<Sr<aj, 529. 



Strobila, of Rhizostomidce, 117 ; of Tceni- 

 ada, 187, 188. 



Stromatopora, 66. 



Strombidve, 295, 330, 339. 



Strombodes, 141. 



Strombus, 339. 



Strophalosia, 3 17. 



Strophodus, 641. 



Strophomena, 317. 



Strophomenidce, 317, 319. 



Struthio, 512. 



Struthionidte, 512. 



Sturgeon, 416, 428. 



Sturionidce, 416, 423, 



Sturnidce, 523, 5i'4. 



^i/iops, 290. 



Sub-brachiata, 4 10. 



