VOLUME XXX 



THE 



NUMBER 2 



Journal of Geology 



A Semi-Quarterly 



Edited By 

 thomas c. ciiamberlin and rollin d. salisb 



With the Active Collaboration of 



STUART WELLER, Invertebrate Paleontology 

 EDSON S. BASTIN, Economic Geology 



ALBERT JOHANNSEN. Petrology 



ROLLIN T. CHAMBERLIN, Dynamic Geology 



ASSOCIATE EDITORS 



SIR ARCHIBALD GEIKIE, Great Britain 



CHARLES BARROIS, France 



ALBRECHT PENCK, Germany 



HANS REUSCH, Norway 



GERARD DeGEER, Sweden 



SIR T. W. EDGEWORTH DAVID, Australia 



BAILEY WILLIS, Leland Stanford Junior University 



CHARLES D. WALCOTT, Smithsonian Institution 



JOHN C. BRANNER, Leland Stanford Junior University 

 RICHARD A. F. PENROSE, Jr., Philadelphia, Pa. 

 WILLIAM H. HOBBS, University of Michigan 

 FRANK D. ADAMS, McGill University 

 CHARLES K. LEITH University of Wisconsin 

 WALLACE W. ATWOOD, Clark University 

 WILLIAM H. EMMONS, University of Minnesota 

 ARTHUR L. DAY, Carnegie Institution 



FEBRUARY-MARCH 1922 



THE GREAT FAULT TROUGHS OF THE ANTILLES - - - . Stephen Taber 89 



THE CHARACTER OF THE STRATIFICATION OF THE SEDIMENTS IN THE RECENT 



DELTA OF ERASER RIVER, BRITISH COLUMBIA, CANADA - W. A. Johnston 115 

 THE STRUCTURAL RELATION OF THE PURCELL RANGE AND THE ROCKY 



MOUNTAINS OF CANADA - -' - - - - Francis Parker Shepard 130 

 ASPECTS OF ONTOGENY IN THE STUDY OF AMMONITE EVOLUTION 



A. E. Trxjeman 140 

 A NEW PHYTOSAUR FROM THE TRIAS OF ARIZONA - - Maurice G. Mehl 144 

 ADAPTING A SHORT-BELLOWS, ROLL-FILM KODAK FOR DETAIL WORK IN THE 



FIELD -- Chester K. Wentworth 158 



SEGREGATION GRANITES ------... Alfred C. Lane 162 



ON THE REPRESENTATION OF IGNEOUS ROCKS IN TRIANGULAR DIAGRAMS 



Albert Johannsen 167 



PETROLOGICAL ABSTRACTS AND REVIEWS - j^o 



REVIEWS - - - -' 175 



THE UNIVERSITY OF CHICAGO PRESS 



CHICAGO, ILLINOIS, U. S. A. 



THE CAMBRIDGE UNIVERSITY PRESS, London 



THE MARUZEN-KABUSHIKI-KAISHA, Tokyo, Osaka, Kyoto, Fdkuoka, Sendai 



THE MISSION BOOK COMPANY, Shanghai 



