Volume XVI Number 5 



THE 



Journal of Geology 



A Semi -Quarterly flagazine of Geology and 

 Related Sciences 



JULY-AUGUST, igo8 



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 G. K. GILBERT 



Great Britain Washington, D. C. 



H. ROSENBUSCH H. S. WILLIAMS 



Germany Cornell University 



CHARLES BARROIS C. D. WALCOTT 



France Smithsonian Institution 



ALBRECHT PENCK J. C. BRANNER 



Germany Stan/ora University 



HANS REUSCH W. B. CLARK 



'Norway Johns Hopkins University 



GERARD DE GEER O. A. DERBY 



Sweden Brazil 



T. W. E. DAVID, Australia 



Ef)e sanibensitg of articago ^xz%% 



CHICAGO AND NEW YORK] 

 WiLLiAU Wesley & Son, London 



