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AMERICAN GEOLOGIST 
A MONTHLY JOURNAL OF GEOLOGY 
AND 
ALLIED SCIENCES. 
Editor: N. H. WINCHELL, Minneapolis, Minn. 
ASSOCIATE EDITORS: 
Florence Bascom, Bryn Mawr, Pa. 
Charles E. Beecher, New Haven, Conn. 
Samuel Calvin, Iowa City, Iowa. 
John M. Clarke, Albany, N. Y. Ulysses S. Grant, Evanston, 111. 
Herman L. Fairchild, Rochester, N. Y.Oliver Perry Hay, New York, N. Y. 
Persifor Frazer, Philadelphia, Pa. George P. Merrill, Washington, D. C. 
Warren Upham, St. Paul, Minn. 
Israel C. White, Morgantown, W. Va. 
Horace V. Winchell, Butte, Mont. 
VOLUME XXXV 
January to June 1905 
Minneapolis, Minn. 
The Geological Publishing Co 
1905 
TBLGRAPH-HERALD PRINT, 
DDBUQUK, IOWA. 
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