VOLUME XXIII 



THE 



NUMBER 4 



Journal of Geology 



A Semi-Quarterly 



Edited By 



THOMAS C. CHAMBERLIN AND ROLLIN D. SALISBURY 



With the Active Collaboration of 



SAMUEL W. WILLISTON 



Vertebrate Paleontology 

 STUART WELLER 



Invertebrate Paleontology 



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 



ORVILLE A. DERBY, Brazil 



T. W. EDGEWORTH DAVID, Australia 



BAILEY WILLIS, Argentine Republic 



GROVE K. GILBERT, Washington. D.C. 



CHARLES D. WALCOTT, Smithsonian Institution 



HENRY S. WILLIAMS, Cornell University 

 JOSEPH P. IDDINGS, Washington, D.C. 

 JOHN C. BRANNER, Leland Stanford Junior University 

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

 WILLIAM B. CLARK, Johns Hopkins University 

 WILLIAM H. HOBBS, University of Michigan 

 FRANK D. ADAMS, McGill University 

 CHARLES K. LEITH, University of Wisconsin 

 WALLACE W. ATWOOD, Harvard University 

 WILLIAM H. EMMONS, Uiiiveisity of Minnesota 



MAY-JUNE 191 J 



THE EVOLUTION OF HERBACEOUS PLANTS AND ITS BEARING ON CERTAIN 

 PROBLEMS OF GEOLOGY AND CLIMATOLOGY 



Edmund W. Sinnott and Irving W. Bailey 289 



POST-CRETACEOUS HISTORY OF THE MOUNTAINS OF CENTRAL WESTERN 



W,^OMING. PART III - - - - - - - - • Eliot Blackwelder 307 



THE GEOLOGY OF CENTRAL MINAS GERAES, BRAZIL. PART I 



E. C. Harder and R. T. Chamberlin 341 



REVIEWS 



379 



THE UNIVERSITY OF CHICAGO PRESS 



CHICAGO, ILLINOIS, U.S.A. 



Agents 



THE CAMBRIDGE UNIVERSITY PRESS, London and Edinbukgh 



KARL W. HIERSEMANN, Leipzig 



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



