INDEX 



695 



(las and oil, Ordovician, 374 

 Gases in igneous rocks, 241 

 ( la-es of volcanoes, 236 

 daMropoiU, Cambrian, 361 



Cretaceous, 554, 555 



Devonian, 417 



Mi.K-ene, 597. 



Ordovician, 380, 381 



Silurian, 397 



Triassic, 499 

 di-antii liius, 277 



Geikie, Sir A., cited, 226, 245, 356 

 Geikie, J., cited, 160, 171, 668, 676 

 Genesee shale, 402 

 Geodes, 286 

 Geology denned, i 

 Geology, subdivisions of, i 



time divisions, 323 

 Georgian epoch, 344 

 Geosaurus suevicus, 515 

 Geosynclines, 277 

 Geysers, 49 

 Gilbert, G. K., cited, 73, 91, 118, 173, 



203, 226, 6*46, 661, 676 

 Glaciated areas, re-peopling, 678 

 Glaciated regions, soil in, 680 

 Glaciated rock surfaces, 161 

 Glaciation and drainage, 632 

 Glaciation, criteria of, 616 



early, 309 



effect on life, 678 

 dlarial climate, cause of, 648 

 Glacial debris, 136, 137 



nature of, 150 



Glacial deposits, nature of, 160 

 Glacial drainage, 138 

 Glacial epochs, 632, 633 

 Glacial erosion, topographic effects of, 



iSi 

 Glacial formations, Cambrian, 356, 357 



Permian, 473 



Proterozoic, 342 

 Glacial period, 613 



duration of, 646 



effect on life, 663 



end of, 677 



time since, 646, 647 

 dlarial planation, 622 

 ( llac ial soils, 680, 681 

 Glacial striae, 148, 161, 622 



arrangement of, 623 

 Glacial tables, 137 

 Glacirr iiv, structure of, 139 

 dlai-ii-r motion and transportation, 



144 



Glaciers, development of, 140 



erosion by, 147 



fluctuations of, 133 



limits of, 132 



movement of, 126, 132, 133, 140, 142, 

 146 



Pleistocene, in western mountains, 657 



structure of, 125, 139, 155 



texture of, 1 26 



transportation by, 140 



types of, 127 



upturning of layers, 155 

 Glaciers and rivers contrasted, 134 

 Glacio-fluvial deposits, 139, 164 

 Glacio-lacustrine stage, 633, 636 

 Glauconite, 532 



origin of, 532 

 Globigerina bulloides, 572 

 Globigerina ooze, 199 

 Glossopteris angustifolia, 478 



communis, 478 



Glossopteris flora, 475, 477, 478 

 Glycerites sulcatus, 386 

 Glycimeris idoneus, 573 

 Glyptocrinus decadactylus, 384 

 Glyptodon, 669 

 Golden Gate series, 505 

 Goldthwaite, J. W., cited, 606 

 Goniatites, 418 

 Goniatites kentuckiensis, 437 



vanuxemi, 419 



Goniobosis (?) ortmanni, 530 

 Goniophyllum pyramidale, 398 

 Gorges, 88 

 Graben, 221 

 Gradation, 2 



cause of submergence, 349 



in sea, 172 

 Grade, 66, 68 



Grammatodon inornatus, 512 

 drammysia hannibalensis, 433 

 Grand Canyon, 86 



Precambrian rocks of, 341 

 Grand Canyon group, 341 

 Grand Gulf formation, 574 

 Granites, 259, 262 

 Granitic rock, 249 

 Granitoids, 263 

 Grant, U. S., cited, 374 

 Graphic granite, 259, 260 

 Graphite, 257 

 Graptolites, 377 



Cambrian, 362 



Ordovician, 385 



Silurian, 399 



