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EDITED BY 
THOMAS C. CHAMBERLIN AND ROLLIN D. SALISBURY ie 
With the Active Collaboration of - 
SAMUEL W. WILLISTON ALBERT JOHANNSEN ts yy: 2 
Vertebrate Paleontology — Petrology ee oR oe teajaniegh ‘ , 
STUART WELLER ROLLIN T. ‘(CHAMBERLIN © re etl a SAT ee 
Invertebrate Paleontology : _ Dynamic Geology 
ALBERT D. BROKAW : 2 aeti et pes 
Economic Geology eae ping aan 
The Journal of Geology is published by the University of Chicago at the University Press semi- 
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