jaa Se: Se EDITED BY rains Gira ieee aa 
THOMAS C CHAMBERLIN AND. ROLLIN D. SALISBURY 
With the Active Collaboration of 
abs sues eens af 
SAMUEL W. WILLISTON ALBERT: JOHANNSEN+#\-<\ 20.i00'1; sea con So ee 
_ Vertebrate Paleontology ; Petrology snag eo 
STUART WELLER ae: ROLLIN T. CHAMBERLIN pesrettiy 
Invertebrate Palebathlonie ; _ Dynamic Geology __ 
ALBERT D. BROKAW y ce ea 
Economic Geology pedis son . eae Mae 
- The Journal of Geology is published by the University of Chicago at the University Press semi- fee 
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