880 



INDEX. 



Page. 



Pah-tsonMountains, AlolaPeak 780 



Archaean scliists 775 



BallEoclss 784 



Basalt Peak 785 



geological structure 775, 780 



granite 778 



Grass cafion 78:J 



PahkealiPeak 776,778,782 



rhyolite 783 



Paii-Ute Kangk (;88 



anticlinal in Star Peak Triaasio — 710 



diorite 696 



geological structure 689 



McKinney's Pass 695 



ihyolite tufas 699 



Sou Spring Hills 696 



Spaulding's Pass 708 



Star Peak Triassic. . . . .' 693, 710 



trachyte 700 



Paueozoic and mesozoic formations (of North 



Park) 114 



FOEMATIONS (of Colorado Kange) 29 



(of Pi flon Eange) . 552 



■Rocks (of Cottonwood Eegion) 362- 



strata of Laramie Plains 75,82 



thickness of, Colorado Kange 28 



Laramie Hills 76 



Kawlings Peak.... 161 



Palagonite tufa. Black Kock Moun tains 794 



Truckee Miocene 768 



Palisade Canon Eegion 585 



quartziftrous augiteandesite 586 



trachyte 585,587 



Pappoose Peak, Cortez Eange, dacite 581 



quartz-prcpylite 560 



Paragonite-schists in Archtean 270, 358 



Paek Eakgb 130 



Archaean 134 



chlorite in gneiss J40, 141 



drainageof 131 



epidote in Archiean 135, 140 



garnet in Archseau 138, 140 



glacial erosion 131 



gold-placers 140, 181 



■lagnetite in Archaean 136,140 



physical description 130 



timber-line , 132 



Park's Station, Colorado Eange, mesozoic strata near. 54 



Parkview Peak, North Park, altitude. ICO 



described 120 



granite-porphyry 122 



magnetite in trachyte. 123 



orthoclase in trachyte. 123 



pyrites in trachyte 123 



trachyte 122 



Parley's Caiion, Dakota conglomerate 372 



Permo-Carboniferous 369 



Park, Wahsatch Eange, altitude 372 



trachyte 384 



Pass Creek, North Platte Valley, described 153 



Patterson Pass, Ombe Mountains, granite 495 



Pearlite, Grass Canon, Pahtsou Monutaius 783 



J uUen's Gap, Virginia Eange 846 



Valley Caiion, Montezuma Eange 759 



Peavine Mountain, Archaean 850 



Page. 



Peavine Mountain, augite-andesite near 851 



Eegion 849 



PekoPeak, Mallard Hills, rhyolite 593 



Pelham Peak, Park Eange, altitude 130 



Pelican Hills, Utah Lake Valley, Wahsatch limestone 442 



Peoquop axd Toaxo Passes 501 



Pass, Green Elver Eocene 501 



Eange 505 



anticlinal in Crawford Pass 510 



geological structure 506 



granite 506 



Upper Coal-Measures 507, 503 



Weber Qnartzite 507 



Peoria, Weber Elver, Utah, thickness of Triassic. . . 332 



Permo-Carboniferous, Flaming Gorge Eidge 265 



Parley's Caiion 369 



Provo Valley 349 



ripple-marks in 389 



SectionEidge 285 



UintaEange 199 



Verm illion Creek Valley 275 



WeberCaiion 389 



Petrified tree, Haystack Mountain 215 



Petroleum in Colorado Cretaceous 252, 329 



Phosphoric acid in obolella 412 



granite 23 



Phragmitis communis 747 



PUYSICAL ASPECT OF THE GBEAT PLAINo 2 



BESCUIPTION OF THE COLORADO ARCH.iBAN 



BODY 18 



Green Eiver Bastn. 191 



LARAkiR Plains 73 



Medicine Bow 



Eange 94 



Nevada Plateau 470 



North Park 112 



Park Eange 130 



UixTA Eange 194 



Wahsatch Eange 340 



Picotitein basalt 730,765 



Pickeringite 424 



Piedmont Station, Green Eiver Eocene 241 



Pilot Butte, Wyoming, augitic trachyte 238 



view of Green Eiver Basin.. 239 



Peak, Nevada, altitude 494 



anticlinal 496 



salt-fields near 501 



salt-springs 501 



Upper Coal-Measures 497 



Eock, Utah, Wahsatch limestone 4C0 



Pine Bulfs, Wyoming, Green Eiver Eocene 213 



Pine Nut Canon, labradoriziug feldspar 701 



rhyolite through trachyte 701 



trachyte 701 



Pass, Piiion Eange 556 



Valley Pliocene 583 



erosionof 583 



Gay-Lussite in 583 



PiSoN Kange 551 



Arcbffian 554 



basalt 560 



geological structure 551 



Green Eiver Eocene 551 



Humboldt Pliocene 551 



Lower Helderberg fossils 557 



