VOLUME XXI 11 



THE 



NUMBER 1 



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, University of Minnesota 



JANUARY-FEBRUARY 191 j 



THE ORIGIN OF THE INCLUSIONS IN DIKES ----- Sidney Powers 



THE MIDDLE AND UPPER DEVONIAN OF THE ROMNEY, WEST VIRGINIA, 

 REGION - . . Charles S. Prosser 



THE STRENGTH OF THE EARTH'S CRUST. VII. VARIATIONS OF STRENGTH WITH 

 DEPTH AS SHOWN BY THE NATURE OF DEPARTURES FROM ISOSTASY 

 (Section B) ------------ Joseph Barrell 



SOME ELLIPSOIDAL LAVAS ON PRINCE WILLIAM SOUND, ALASKA -- S. R. Capps 



A SKETCH OF THE LATE TERTIARY HISTORY OF THE UPPER MISSOURI RIVER 



Clyde Maxwell Bauer 

 THE INTERGLACIAL GORGES OF SIX MILE CREEK AT ITHACA, NEW YORK 



John Lyon Rich and Edwin A. Filmer 



SUMMARIES OF PRE-CAMBRIAN LITERATURE OF NORTH AMERICA FOR 1909, 



1910, 191 1, AND PART OF 191 2 - - - - - - Edward Steidtmann 



REVIEWS 



27 

 45 



52 

 59 



81 

 92 



THE UNIVERSITY OF CHICAGO PRESS 



CHICAGO, ILLINOIS, U.S.A. 



Agents 



THE CAMBRIDGE UNIVERSITY PRESS, London and Edinburgh 



KARL W. HIERSEMANN, Leipzig 



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



•^' p. Iddin; ; 



COLLECTION y, 



