424 



INDEX. 



Pterosaur (winged lizard), 337. 

 Pumice, 214. 



Quaternary period, 385. 



period in Eastern North Amer- 

 ica, 386. 



period in Western North Amer- 

 ica, 393. 



period, life-system of, 397. 



period, mammals of, in Amer- 

 ica, 398. 



period, mammals of, in Aus- 

 tralia, 402. 



period, mammals of, in Eu- 

 rope, 397. 



period, mammals of, in South 

 America, 401. 



period, subdivisions of, 385. 



Rafts, 88. 



Rain and rivers, erosive action of, 

 18. 



final effect, 28. 



rate of erosion by, 19. 

 Ramphorhynchus (beak-snout), 



338. 



Range of species, genera,etc., 120. 

 Ravines, gorges, cafions, 23. 

 Reefs and keys of Florida, 109. 



how formed, 111. 

 Reefs of Pacific, 97. 

 Regions, botanical, 119. 



definition of, 120. 



primary, 128. 



primary, subdivisions of, 128. 



zoological, 122. 

 Reptiles, age of, 324. 

 Rhyolite, 214. 

 River-beds of California, old, 395. 



as indicators of crust-move- 

 ments, 28, 170. 



deltas, subsidence of, 169. 



drift-man in America, 414. 

 Rivers, deposits at the mouths of, 

 38. 



deposits of old, 392. 



erosive action of, 30. 



flood-plain deposits of, 30. 



winding course of, 29. 

 Rock disintegration, rate of, 13. 



disintegration, explanation of, 



Rocks, classes of, 178. 



Rocks, defined, 178. 



igneous, 210. 



metamorphic, 224. 



stratified, cause of consolida- 

 tion of, 182. 



stratified, classification of, 205. 



stratified, description of, 179. 



stratified, extent of, 180. 



stratified, origin of, 181. 



stratified, principal kinds of, 

 180. 



structures common to all, 228. 



unstratified, 210. 



St. Anthony, Falls of, 22. 

 Saline lakes, how formed, 76. 



lakes, chemical deposits in, 76. 

 Salt lakes, how formed, 77. 

 Sauropus (lizard-foot), 321. 

 Scaphites (stone-boat), 353. 

 Sea-beaches, elevation of, 391. 

 Section of earth-crust, ideal, 261. 

 Sediments, transportation and 



distribution of, 26. 

 Sequoia : genus of conifers, in- 

 cluding Redwoods and Big 

 Trees of California, 368. 

 Sertularia (a little garland), 276. 

 Sharks, 291, 318, 354, 373. 

 Shell limestone, how formed, 114. 



mounds, 412. 

 Sierra Nevada range, formation 



of, 348. 

 Sigillaria (from sigillum, a seal), 



308. 



Sigillarid, 287, 308. 

 Silica, deposits of, 76. 

 Silurian animals, 275. 

 rocks, area of, in the United 



States, 273. 

 system, 271. 



times, life-system of, 273. 

 times, plants of, 274. 

 times, subdivisions of, 273. 

 times, physical geography of, 



273. 



Slaty cleavage, 194. 

 Snow-line, 53. 

 Soil, depth of, 12. 



origin of, 10. 

 Solfataras (hot sulphur springs), 



145. 

 Sorting power of water, 27. 



