The Journal of Geology 



Edited By 



THOMAS C. CHAMBERL1N AND ROLLIN D.SALISBURY 



With the Active Collaboration of 



SAMUEL W. WILL1STON ALBERT JOHANNSEN 



Vertebrate Paleontology Petrology 



STUART WELLER ROLLIN T. CHAMBERL1N 



Invertebrate Paleontology Dynamic Geology 



ALBERT D. BROKAW 



Economic Geology 



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