THE PLEISTOCENE OR GLACIAL PERIOD 847 



greatest to the southwest, and in this direction the limit is some 

 1,600 miles from the center of dispersion, in latitude about 37 30', 

 the most southerly point of the great lowland glaciation of the 





Fig. 580. Sketch-map showing the North American area covered by ice 

 at the stage of maximum glaciation. 



period. The extension of the Keewatin ice-sheet to the southward 

 was scarcely less. It found its limit in Kansas and Missouri, about 

 1,500 miles from its center, while to the west and southwest it 

 reached 800 to 1,000 miles toward the Rocky Mountains. One of 



