426 



INDEX. 



Robulina, 322. 



Rocks, definition of, 15; divisions of, 

 15, 16; igneous, 15; aqueous, 17-19; 

 mechanically-formed, 19-21 ; chem- 

 ically - formed, 21 ; organically- 

 formed, 21-38; arenaceous, 21; argil- 

 laceous, 21; calcareous. 21-33; sili- 

 ceous, 21,33-35. 



Rodentia of the Eocene, 316; of the 

 Miocene, 333; of the Post-Pliocene, 

 375. 



Roebuck. 349, 368. 



Hostellana, 214, 303. 



Jtotalia, 23, 99, 175, 272; Boueana, 272. 



Rugose Corals, 105; of the Lower 

 Silurian, 106; of the Upper Sil- 

 urian, 121; of the Devonian, 144; 

 of the Carboniferous, 176-177 ; of the 

 Permian, 251; of the Upper Green- 

 sand, 274. 



Rupelian Clay, 318. 



Sabal major, 319. 

 Sabre-toothed Tiger, 333, 343. 

 Saccammina, 175. 

 Saccosoma, 239. 

 Salamanders, 193, 324. 

 Salina, Group, 119. 



Salmonidce, 284. 



Sao hirsuta, 85. 



Sassafras cretacea, 271. 



Sauropterygia, 225. 



Scalaria, 279, 303 ; Orcelandica, 351. 



Scaphites, 281, 282; cequalis, 282. 



Schizodus, 203, 217. 



Schoharie Grit, 137, 139. 



Scolecoderma, 83. 



Scoliostoma, 219. 



Scolithus, 83 ; Canadensis, 108. 



Scorpions of the Coal-measures, 185. 



Scorpion-shells, 280. 



Screw-pines, 237. 



Scutetta, 822 ; subrotunda, 323. 



Sea-cows (see Sirenia). 



Sea-lilies (see Crinoidea). 



Sea-lizards (see Enaliosaurians). 



Seals, 333. 



Sea-mats and Sea-mosses (see Poly- 



zoa). 



Sea-shrubs (see Gorgonidse). 

 Sea-urchins (see Echinoidea). 

 Sea-weeds, 80, 81, 84, 98, 138, 167, 269. 

 Secondary period, 45. 

 Sedimentary rocks, 15. 

 Semnopithecus, 334, 343. 

 Septaria, 32. 

 Sequoia, 316,320 ; Couttfix, 320 ; gigantea, 



320; Langsdorffi,3'2Q. 

 Scrolls, 84. 



Serpents (see Ophidia). 

 Serpulites, 125. 



Sewalik Hills (see SiwAlik Hills). 

 Sheep, 369. 

 Shell-sands, 20. 

 SigUlaria, 170, 172; Orceseri, 172. 

 Sigillarioids. 138, .70, 173,200. 

 Silicates, in filtration of the shells 



of Foraminifera by, 35, 74. 

 Siliceous rocks, 21, 33. 

 Siliceous Sponges, 273. 



Silicification, 13, 14. 



Silurian period (see Lower Silurian 

 and Upper Silurian), 91-116, 117-134. 



Simosaurus, 224 ; (.laillardoti, 224. 



Siphonia, 272;ficw>, 273. 



Siphonostomatous Univalves, 241, 

 280, 303. 



Siphonotreta, 112. 



Sirenia, 309, 331 ; of the Eocene, 309 ; of 

 the Miocene, 326. 



Siren lacertina, 204. 



Sivatherium, 329 ; giganteum, 329. 



Siwalik Hills, Miocene strata of, 318. 



Skiddaw Slates, 102. 



Sloths, 326, 363, 364. 



Smilax, 320. 



Smithia, 176. 



Snakes (see Ophidia). 



Soft Tortoises, 306. 



Solarium, 279. 



Solenhofen Slates, 235. 



Solitaire, 359, 361. 



Spalacotfierium, 262. 



Spatangus, 322. 



Sphcerospongia, 141. 



Sphagodus, 132. 



Sphenodon, 224. 



Sphenopteris, 138, 167, 200. 



Spiders of the Coal-measures, 185. 



Spider-shells, 244. 



Spindle-shells, 244. 



Spirifera,I28, 149, 188, 202, 241; crispa, 

 129; disjuncta, 149; hysterica, 128; 

 mucronata, 149 ; Niagarensis, 1 29 ; ros- 

 trata, 242 ; sculptilis, 149 ; trigoncUis, 

 189. 



Spiriferidse, 149. 



Spirophyton cauda-Oatti, 137, 167. 



Spirorbis, 125, 145, 182; Arkonensis, 146; 

 Carbonarius, 182; laxus, 146; Lewisii. 

 12- ; omphalodes, 146; swrmfyfero, 146. 



Spirulirostra, 323. 



Spondylus, 277 ; spinosus, 278. 



Sponges, of the Cambrian, 82 ; of the 

 Lower Silurian, 99 ; of the Upper 

 Silurian, 120; of the Devonian, 

 141; of the Carboniferous, 175; of 

 the Permian, 201 ; of the Trias, 214; 

 of the Jurassic, 237; of the Cre- 

 taceous, 272, 273. 



Spongilla, 201. 



Spongillopsis, 201. 



Spongophyllum, 176. 



Spore-cases, of Cryptogams in the 

 Ludlow rocks, 120; in the Coal, 165. 



Squirrels, 334. 



Stagonolepis, 224. 



Staircase-shells, 279. 



Stalactite, 22. 



Stalagmite, 22. 



Star-corals, 238. 



Star-fishes, 106, 122. 216. 



St. Cassian Beds. 209, 210. 



Stephanophyllia, 274. 



Stereognathus, 261, 262. 



Stigmaria. 173;flcoides, 173. 



Stouesfield Slate, 234; Mammals of, 

 261. 



Strata, contemporaneity of, 45. 



Stratified rocks, 16-19. 



Streptelasma, 106. 



Streptorhynchus, 202. 



