THE JOURNAL OF 
EDITED BY 
THOMAS C. CHAMBERLIN AND ROLLIN D. SALISBURY ae 
With the Active Collaboration of | Set 
STUART WELLER _ ALBERT JOHANNSEN- oh mt 
Invertebrate Petcontaloey ; 
EDSON S. BASTIN ROLLIN T. . CHAMBERLIN 
Economic Geology 
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Entered as second-class matter, March 20, 1893, at the Post-office at Chicago, Ill., under tl 
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