THE 
PMERICAN GEOLOGIST 
A MONTHLY JOURNAL OF GEOLOGY 
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, Ill. 
HERMAN L. FAIRCHILD, Rochester,N. Y. GEORGE P. MERRILL, Washington,D.C. 
PERSIFOR FRAZER, Philadelphia, Pa. WARREN UPHAM, St. Paul, Minn. 
ISRAEL C. WHITE, Morgantown, W. Va. 
HORACE V. WINCHELL, Butte, Mont. 
VOLUME XXIX 
JANUARY TO JUNE, 1902 
MINNEAPOLIS, MINN. 
THE GEOLOGICAL PUBLISHING CO. 
1902 
THE UNIVERSITY PRESS OF MINNESOTA. 
