Volume XVI 



Number i 



THE 



Journal of Geology 



A Semi "Quarterly flagazine of Geology and 

 Related Sciences 



((V^'O^' 



JANUARY-FEBRUARY, igo. 



EDITORS 



T. C. CHAMBERLIN, m General Charge ^^'^„ , '^' 



R. D. SALISBURY R. A. F. PENROSE, Jr. "-<s;s,_;^^^seun 



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 



Gerinany 

 CHARLES BARROIS 



France 

 ALBRECHT PENCK 



Germany 

 HANS REUSCH 



Norway 

 GERARD DE GEER 



Sweden 



G. K. GILBERT 



Washington, D. C. 

 H. S. WILLIAMS 



Cornell University 

 C. D. WALCOTT 



Smithsonian Instittition 

 J. C. BRANNER 



Stanford, University 

 W. B. CLARK 



Johns Hopkins University 

 O. A. DERBY 



Brazil 



T. W. E. DAVID, Australia 



CHICAGO AND NEW YORK 

 WiLLiAU Wesley & Son, London 



