INDEX TO VOLUME 12 



533 



Officers, Election of. 453 



— , List of. 513 



— of Cordilleran Section, Election of.......".'.'. 493 



Ohio basin, Exti-a-glacial abandoned val- 

 leys of, hypothesis to account for 462 



Oklahoma, Native copper near Enid in 2 



Oligocene period, 'Physical history of 

 Rocky Mountain region in 90 



— rocks, Coldwater group 80 



— formations, Occurrence of, in British 



Columbia 80 



Ombe mountains, Utah, Structure of 221 



Omimi glacial lake, Position and extent of... 126 

 Oneida conglomerate. Unconformity be- 

 tween Hudson River shale and 164 



Onnamani glacial lake, Position and extent 



of. 126 



Ontaeio, Marine and freshwater beaches of. 129 



— , Shell-bearing gravels in 132 



Oquirrh mountains, Utah, Structure of 220 



Ordovician formations. General relation- 

 ships of, in Kentucky and Tennessee... 4.31 



— period. Physical history of the Rocky 



Mountain region in 85 



— rocks in the Rocky Mountain region, 



Occurrence of. 68 



Oregon, "Three Sisters" in, notes on the 

 geology of. 498 



Origin and age of an Adirondack augite 

 syenite [abstract] ; H. P. Gushing. 464 



structure of the Basin ranges ; J. E. 



Spurr 217 



Osgood formation in Tennessee, Character 

 and occurrence of 405 



Otisville, New York, Unconformity be- 

 tween Oneida conglomerate and Hud- 

 son River shales at 164 



Ozark dome, Age of I93 



Pahranagat range, Nevada, Structure of..... 236 



Pahroc range, Nevada, Structure of 2.S6 



Pah Ute range, Nevada, Structure of. 224 



Paleozoic limestones of Kittatinny valley. 

 New Jersey ; Henrv B. Kiimmel and 

 Stuart Weller 147 



— rocks, Rigaud mountain, Occurrence and 



character of. 382 



— time in southern Arizona, Evidences of 



shallow seas in 493 



Pancake range, Nevada, Structure of. 229 



Parker channel. The alleged 463 



Pasadena, California, Sierra Madre near 494 



Pease, L. B., Analysis of limestone by 367 



Pebbly sandstone in Lake Superior sand- 



' stone 200 



Pedological geology of California, Sketch of 499 

 Pegram, Tennessee, List of fossils from 443 



— limestone, Devonian fossils of, in Ten- 



nessee 444 



, Occurrence, character, and thickness 



of. 425 



Peneplains of central France and Brittany 



(The) [abstract] ; W. M. Davis 480 



Penfield, 8. L., becomes life member 451 



— , Title of paper by 472 



Penhallow, D. p., cited on fossils from 



British Columbia 82 



Pennsylvania, Age of the coals at Tipton, 



Blair county 473 



— , Potholes in 38 



Penokee RANGE, Fcaturcs of 200 



Peoquop RANGE, Ncvada, Structure of 222 



Pepin, Lalie, origin of 22, 2 



Permian period. Physical history of Rocky 



Mountain region in 86 



Phosphatic rock, Tennessee, Occurrence, 



character, and thickness of. 428 



Photograph Committee, Appointment of, 



recommended by Council 479 



, Eleventh annual report of 465 



LXXV— Bull. Geol. Soc. Am., Vol. 12, 1900 



Page 



Pinenut range, Nevada, Structure of 231 



Pinon range, Nevada, Structure of. 22 



" Pipes," a concretionary form, Occurrence 



of. 166 



— , Figures showing 166 



Platform beaches, Wisconsin shore of lake 



Superior 212 



Platt, Franklin, Announcement of death 



of. 447 



— , Bibliography of 455 



— cited on coals of Tipton, Pennsylvania.... 477 

 formations at Tipton, Pennsylva- 

 nia 473 



—.Memoir of 454 



Platte river. Flood relief channel of Shell 

 creek and Loup fork and, in eastern 



Nebraska 488 



Pleistocene deposits, Occurrence of, in 

 Ontario, Canada .- 129 



— erosion of the Dalles of the Saint Croix ... 18 



— ice and river erosion in the Saint Croix 



valley of Minnesota and Wisconsin ; 

 Warren Upham 13 



— lakes. Erosion in drainage basins of 251 



— period. Deformation in the Great Basin 



province during 247 



, Erosion in the Great Basin province 



during 249 



, Physical history of Rocky Mountain 



region in 91 



Pliocene period. Deformation in the Great 



Basin province during 246 



, Physical history of Rocky Mountain 



region in 90 



— rocks in British Columbia, Supposed oc- 



currence of 82 



Points involved in the Siluro-Devonian 

 boundary question [abstract] ; H. S. 



Williams 472 



PoRPHYRiTic granite in Georgia, Character 



and composition of. 97 



from Georgia, Analyses of. 98 



near Palmetto, Georgia, plates show- 

 ing . 96 



, Residual clays from, plates show- 

 ing 97 



Poteau formation. Coals of 182 



, Correlation of. 181 



Potholes, Classification of 27 



— , Comparison of glacial streams of eskers 



and 42 



— , Conditions of erosion of. 41 



— , Glacial characters of. 28 



— , Localities of. 34-41 



— , Subglacial, localities of 29 



Powell, J. W., cited on cliffs of the Colorado 



plateau 256 



deformation m the Great Basin prov- 

 ince 248 



structure of the Colorado plateau..... 240 



— quoted on origin of the Basin ranges 261 



Preglacial rivers in Saint Croix valley....... 16 



President, Annual address of. 57 



— , C. D. Walcott elected .'. 453 



Presque isle, lake Superior, Tombolo at 212 



Prestwich, Joseph, quoted on Old Red sand- 

 stone of Herefordshire 311 



Prime, Frederick, Jr., cited on the Magne- 

 sian limestones 154 



Proceedings of the Twelfth Summer Meet- 

 ing, held at New York city, June 26, 

 19U0; H. L. Fail-child, Secretary 1 



Thirteenth Annual Meeting, held at 



Albany, New York, December 27, 28, 

 and 29, 1900, including Proceedings of 

 the Second Annual Meeting of the Cor- 

 dilleran Section, held at San Francisco, 

 December 28 and 29, 1900 ; H. L. Fair- 

 child, Secretary 445 



Promontory range, Utah, Structure of 220 



Puget beds. Age of 79 



