758 The Glactated Area of North America. [August, — 
plements.’ Professor Cook has also found in these same glacial 
gravels the tusk of a mastodon. In riding from New York to 
Philadelphia on the New Jersey Central railroad, the train passes 
ylvania. This and the re- 
O, Indiana and Kentucky,” published by the Cleveland 
y of glaciated area of Penns 
Fic. 3.—The broad, black line shows southern boundar 
maining figures are from the “ Glacial Boundary in Ohi 
Historical Society. 
en, and 
from the glaciated to the unglaciated region at Metuchen, * 
on the Bound Brook route at Plainfield, and in both g5 w 
boundary line is marked by extensive accumulations ; 
1 See his “ Primitive Industry,” Salem, Mass., 1881. 
