GEOLOGIA 
VOLUME XIII (New Series) 
Ity, ^ Zt DECEMBER, 1915 
NUMBER 4 
tural History 
Society 
PUBLISHED WITH THE COOPERATION 
OF THE 
Public Museum of the City of Milwaukee 
EDITOR: 
RICHARD A. MUTTKOWSKI 
ASSOCIATE EDITORS: 
P. H. DERNEIIL HOWLAND RUSSEL EDGAR E. TELLER 
