10 BULLETIN 142, U. S. DEPARTMENT OF AGRICULTURE. 
The ice sheet which occupied the basin of Lake Erie was continued 
southward in lobes which approximately coincided with the basin 
of the Scioto River, that of the Maumee and Miami Rivers, and 
another which extended westward through the Maumee Basin and 
overspread the northeastern and central part of Indiana as far as 
Indianapolis and the drainage of the Wabash River. From the 
deposits formed by this glacier the plains of western Ohio and east- 
ern and central Indiana were formed, and these are extensively 
occupied by the soils of the Miami series. 
Another large lobe of this glaciation extended southwestward 
through the Saginaw Bay region as far south as the northern part 
of Indiana. To the east its margin joined that of the Huron-Erie 
lobe, and the combined deposits of the two give rise to the rolling 
and hilly territory which extends southwestward from the " thumb " 
of Michigan to the vicinity of Logansport, Ind. It laid down the 
materials which constitute the ridged plains of central Michigan 
from Saginaw to the vicinity of Jackson and Kalamazoo. It did not 
extend entirely to the shore of Lake Michigan, but adjoined a larger 
lobe, which occupied the basin of Lake Michigan. Along the junc- 
tion of these two lobes were formed deep and extensive deposits of 
ice-borne material along the eastern border of the lake from the 
vicinity of Newaygo to the Indiana State line. 
The Lake Michigan lobe was almost coextensive with the present 
area of that lake, but extended slightly beyond its present bound- 
aries, and laid down deposits which circle the lower extremity of 
the lake, giving rise to soils of the Miami series in northern Indiana 
and northeastern Illinois. 
Another lobe of the Wisconsin glaciation extended to the south- 
west through the basin now occupied by Green Bay and Winnebago 
Lake. The front of this lobe and of the smaller Delavan lobe ex- 
tended from the vicinity of Beloit, Wis., beyond Madison and 
Portage, and thence northward into central Wisconsin. Along the 
line of its juncture with the Lake Michigan lobe extensive and deep 
glacial deposits were formed which accentuate the area of highland 
separating the Green Bay basin from that of Lake Michigan. 
When the ice sheet of the Wisconsin glaciation advanced to its 
extreme limit it extended over a region which had previously been 
glaciated one or more times. It filled the existing valleys and deeply 
covered the interstream ridges and hills. Its base rested upon the 
unconsolidated deposits of the previous invasions and upon exposed 
ledges of consolidated rock of various character and hardness. The 
ice scoured and eroded these surfaces, picked up masses of rock, 
gravel, sand, and clay, and after thoroughly mixing them trans- 
ported the material a varying distance along its path. It is prob- 
able that a large part of this reworking and transportation was 
