INDEX. 



681 



Piracy, 



extent of, in Appalachians, 170 



foreign, 104 



of Kaaterskill Creek, 105 



of Plaaterskill Creek, 105 

 Pirsson, Louis V., 412 451, 573 

 Pisolite, 465, 496 

 Pitchstones. 408, 453, 472 

 Plagioclase, 465 

 Plain, 



alluvial, 181, 184 



graded, 169 



outwash, 306 

 Plaaation, 82 



Plant kingdom, geologic contri- 

 butions of, 652-658 

 Plant life and carbon dioxide, 



665 

 Plant societies, 667 

 Plants, 



contributions to deposits, 652- 

 658 



contribution to limestone, 654 



effect on erosion, 131, 644 



reference table of, 653 



weathering influenced by, 112 

 Platte River, 187 

 Plaaterskill Creek, piracy of, 105 

 Plugs, volcanic, 591 

 Plumbago, 465 

 Plunging anticline, 155 

 Plutonic rocks, 472 

 Polar glaciers, 254 

 Poincare, H., 576 

 Polic rocks, 456 

 Polmitic rocks, 457 

 Ponding of streams, 171 

 Po River, delta of, 202 



sediment carried by, 107 

 Porphyries, 453 

 Porphyrite, 472 

 Porphyritic rocks, 411 

 Porphyry, 472 

 Posepny, F., 474 

 Potash, in sea-vrater, 377 

 Pot holes, 140 

 Potomac River, 168 



sediment carried by, 107 

 Potonie, H.. 652 

 Powell, J. W,, 519, 521 

 Precipitation, 50 



from atmosphere, 51 



from solution, 41, 225, 239, 

 375-379 

 Precipitation from solution, 



conditions influencing. 225 



influenced by algae, 225 

 Pressures within earth, based on 



Laplace's law, 564 

 Prestwich, J., 203, 225 

 Propylite, 472 

 Protogine, 472 

 Protozoa, geologic contribution 



of, 660 

 Provincial faunas, 668 

 Pseudomorphs. 465 

 Psilomelane 465 

 Psychological factors 65J 

 Pteridophytes. geologic contri- 

 bution of, 657 



I Pteropod ooze, 380, 382 

 "Pulpit rocks," 350 

 Pumice, 406, 453, 472 

 Push moraine, 301 

 Puzzalana, 405 

 Pyrite, 465 



Pyroclastic rocks, 404, 406, 472 

 Pyrolic rocks, 457 

 Pyroxene, 400, 465 

 Pyroxenite, 417, 452, 472 



Quaquaversal dip, 504 

 Quardofelic rocks, 456 

 Quarfelic rocks, 456 

 Quartz, 466 

 Quartzite, 447, 472 

 Quartz-leucophyres, 453 

 Quartzophyres, 453 

 Quartz-porphyries, 453 



Radiolarian ooze, 380, 382, 425, 

 I 661 



I Rain, 

 I amount of, 51 



erosion by, 57 

 ; mechanical work of, 51 

 Rain-drop impressions, 490 

 Rainfall, efiect on erosion, 128 

 Ransome, F. L., 130, 5x3 

 Rapids, development of, 133, 146 

 Rate of erosion, conditions af- 

 fecting, 123 

 Ravine, 64 



Raymond, R. "W., 474 

 Reade, T. M., 225, 366, 561, 572 

 Reconstructed glacier, 256 

 Red clay, 380, 383, 384 

 Red mud, 380 



Red River of Louisiana, 188 

 Reid, H. F., 256, 259, 261 

 Regolith, 400, 472 

 Rejuvenation of streams, 162 

 163 



criteria of. 164, 165, 166 

 Relief, 



of lithosphere, 11 



of ocean basins, 11 



representation on maps. 30 

 Relief of pressure, a cause of 



volcanic action, 627 

 Rendu, L. C, 321, 322 

 Restrictive evolution, 672 

 Reversed fault, 517, 521 

 Reyer, E., 636 

 Rhine River, material in solution 



in, 108 

 Rhizopoda, geologic contribu- 

 tions of, 660 

 Rhone River, 



delta of, 203 



material in solution in, 108 



sediment carried by, 107 

 Rhyolite, 472 



Rhyolitic structure, of lavas, 41 

 Ricard. T. A., 474 

 Richthofen, Baron von, 23, 604, 



614, 615 

 Rigidity, distribution of, 578 

 Rill-marks. 372, 489 

 Rink, H., 248 



Ripple-marks, 371, 489 



due to wind, 37 

 Rio Grande River, sediment of, 



107 

 River lakes, 198 

 River erosion (see Stream ero« 



sioii) 

 Roanoke River, 168 

 Roches Moutonnees, 304 

 Rock breaking, by changes of 



temperatxire, 44, 49 

 Rocks 



alferric, 454 



alkalicalcic, 458 



alkalimirlic, 458 



alterations of ,426 



aqueous, 467 



arenaceous, 468 



autoclastic, 444 



calcimiric, 458 



"chimney," 350 



chloritic, 431 



classification and nomencla- 

 ture, 449 



clastic, 468 



crystalline, 16 



determination of age, 15 



disruption by hydration, iii 



docalcic, 458 



dofemic, 454 



doferrous, 459 



dohemic, 457 



dolenic, 456 



domagnesic, 459 



domalkalic, 458 



domilic, 457 



domiric, 458 



domirlic, 458 



domitic, 457 



dopolic, 456 



dopotassic, 458 



dopyric, 457 



doquaric, 456 



dosalic, 454 



dosodic, 458 



dotilic, 457 



eolian, 469 



femic, 454 



glassy, 406 



holocrystalline, 412 



hypogene, 470 



igneous, 16. 393, 498 



leading elements of, 396 



lendofelic, 456 



lenfelic. 456 



magnesiferrous 459 



meta-igneous, 471 



metamorphic, 16 



mirlic, 458 



mi tic, 456 



organic, 646 



origin and descent of, 393-483 



peralkalic, 458 



percalcic. 458, 459 



perfelic, 456 



perfemic 454 



perferrous. 459 



perhemic 457 



perlenic 456 



permagnesic 459 



