eae ketmiar 1921 
EDITED BY 
THOMAS C. CHAMBERLIN AND ROLLIN D. SALISBURY 
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With the Active Walhortian of 
STUART WELLER _ ALBERT JOHANN SEN" 
Invertebrate Paleontology , Petrology ; 
EDSON S. BASTIN | ROLLIN ‘TL. CHAMBERLIN. 
Economic Geology Dynamic Geplnay. ee * ; ; 
ee Be MANET T MRD TL Te IgA RT UIE te ee REY i 
The Journal of Geology is published by the University of Giscies at the University of Chicago we 
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