THE WORK OF GLACIERS 



185 



J. Lakes and Ponds. — A glance at any good map of the United 

 States shows that south of the limit of glaciation lakes are almost 

 ahsent except (1) those formed by rivers in their meanderings (p. 

 120) ; (2) those in limestone regions {e.g., Florida) (p. 69) ; and 





FlG. 172. — Map showing the great abundance of lakes in a portion of a 

 glaciated region. Ashby Quadrangle, Minnesota. 



(3) those formed by wave and current action along the coast (p. 220)0 

 This condition is in decided contrast to that in the glaciated portions 

 (Fig. 172). The depressions in which lakes and ponds occur were 



Fig. 173. — The Fulton chain of lakes in the Adirondacks, New York. First, 

 Second, Third, Fourth, Fifth, Sixth, and Seventh Lakes are evidently the result of 

 the partial filling of a preglacial river channel with glacial drift. 



