Volume XIII 



Number 4 



THE 



Journal of Geology 



A Semi "Quarterly flagazine of Geology and 

 Related Sciences 



MAY-JUNE, 1905 



EDITORS 



T. C. CHAMBERLIN, in General Charge 



R. D. SALISBURY R. A. F. PENROSE, Jr. 



Geographic Geology Economic Geology 



J. P. IDDINGS C. R. VAN HISE 



Petrology Structural Geology 



STUART WELLER W. H. HOLMES 



Paleontologic Geology Anthropic Geology 



S. W. WILLISTON, Vertebrate Paleontology 



ASSOCIATE EDITORS 



SIR ARCHIBALD GEIKIE 



Great Britain 

 H. ROSENBUSCH 



Germany 

 CHARLES BARROIS 



France 

 ALBRECHT PENCK 



Austria 

 HANS REUSCH 



Norway 

 GERARD DE GEER 



Sweden 



O. A. DERBY 



Brazil 



G. K. GILBERT 



Washington, D. C. 

 H. S. WILLIAMS 



Yale University 

 C. D. WALCOTT 



U. S. Geological Survey 

 J. C. BRANNER 



Stanford University 

 I. C. RUSSELL 



University of Michigan 

 W. B. CLARK 



fohns Hopkins University 



Cfje sanibersitg oi (Kfjicago tresis 



CHICAGO AND NEW YORK 

 William Wesley & Son, London 



