The Journal of Geology 



Edited By 

 thomas c.chamberlin and rollin d.salisbury 



With the Active Collaboration of 



SAMUEL W. W1LLISTON ALBERT JOHANNSEN 



Vertebrate Paleontology Petrology 



STUART WELLER ROLLIN T. CHAMBERL1N 



Invertebrate Paleontology Dynamic Geology 



ALBERT D. BROKAW 



Economic Geology 



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Entered as second-class matter, March 20. 1893. at the Post-office at Chicago, I!!., under the Act of March a, 1879. 



