VOLUME XIX 



NUMBER 8 



THE 



Journal of Geology 



A Semi-Quarterly 



. Edited By 



THOMAS C. CHAMBERL1N AND ROLLIN D. SALISBURY 



With the Active Collaboration of 



SAMUEL W. WILLISTON 



Vertebrate Paleontology 



STUART WELLER 



Invertebrate Paleontology 



ALBERT JOHANNSEN 

 Petrology 



WALLACE W. ATWOOD 

 Physiography 



WILLIAM H. EMMONS 



Economic Geology 



ROLLIN T. CHAMBERLIN 

 Dynamic Geology 



ASSOCIATE EDITORS 



SIR ARCHIBALD GEIKIE, Great Britain 



HEINRICH ROSENBUSCH, Germany 



THEODOR N. TSCHERNYSCHEW, Russia 



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, National Survey, Washington, D.C. 

 CHARLES D. WALCOTT, Smithsonian Institution 

 HENRY S. WILLIAMS, Cornell University 

 JOSEPH P.IDDINGS, Washington, D.C. 

 JOHN C. BRANNER, Stanford 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 



NOVEMBER-DECEMBER, 191 1 



CONTENTS 



THE BEARINGS OF RADIOACTIVITY ON GEOLOGY ----- T. C. Chamberlin 673 

 THE WING-FINGER OF PTERODACTYLS, WITH RESTORATION OF NYCTOSAURUS 



S. W. WlLLISTON 696 



THE TERRESTRIAL DEPOSITS OF OWENS VALLEY, CALIFORNIA 



Arthur C. Trowbridge 706 



ON CORUNDUM-SYENITE (URALOSE) FROM MONTANA - 



Austin F. Rogers 748 



A DRAWING-BOARD WITH REVOLVING DISK FOR STEREOGRAPHIC PROJEC- 

 TION -------------------- -Albert Johannsen 752 



REVIEWS 



756 



C^e GJnifcergit? of Chicago pvz$$ 



CHICAGO, ILLINOIS 



Agents : 



THE CAMBRIDGE UNIVERSITY PRESS, London and Edinburgh 



WILLIAM WESLEY & SON, London 



TH. STAUFFER, Leipzig 



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



