THE CONTINENTAL GLACIERS OF THE "ICE AGE" 299 



From the still earlier glacial period our data are naturally much 

 more meager, but it seems probable that it was characterized by 

 glaciated areas within both the northern and the southern hemi- 

 spheres. 



Contrast of the glaciated and nonglaciated regions. Since 

 we have now studied in brief outline the characteristics of the exist- 

 ing continental glaciers, we are in a position to review the evidences 



FIG. 325. Map of the glaciated and nonglaciated areas of northern Europe. The 

 strongly marked morainal belts respectively south and north of the Baltic depres- 

 sion represent halting places in the retreat of the latest continental glacier (com- 

 piled from maps by Penck and Leverett). 



of former glaciers, the records of which exist in their carvings, their 

 gravings, and their deposits. 



An observant person familiar with the aspects of Nature in both 

 the northern and southern portions of the central and eastern 

 United States must have noticed that the general courses of the 

 Ohio and Missouri rivers define a somewhat marked common border 

 of areas which in most respects are sharply contrasted (Fig. 324). 

 Hardly less striking is the contrast between the glaciated and the 

 nonglaciated regions upon the continent of Europe (Fig. 325) . 



It is the northern of the two areas which in each case reveals the 

 characteristic evidences of glaciation, while there is entire absence 



