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auriferous gravels, indicating that the latter are, in part at least. Eocene. 

 This discovery is important because the auriferous gravels have been relied 

 upon in determining the age of the Sierra peneplain. 



c. w. w. 



The Drumlins of Southeastern Wisconsin. (Preliminary Paper.) 



By William C. Alden. Pp. 46, 9 plates. Washington, D. C, 



1905. 



There are about 1,400 drumlins in this district, an area of some 4,200 



square miles. The drumlins are distributed over the ground moraines of 



the Green Bay and Lake Michigan glaciers and have their longer axes in 



the direction of ice movement. They are all the product of the last ice 



invasion, at least so far as shaping is concerned. Over 90 per cent, of the 



drift in the drumlins of the Green Bay Glacier is of local derivation; about 



9 per cent, must have been brought from the Canadian crystalline rocks. 



c. w. w. 



