12 BULLETIN 142, U. S. DEPARTMENT OF AGRICULTURE. 



Bowlders and larger stones are more numerous within the moraine 

 areas, especially those crystalline and other extraneous rock masses 

 which were in all probability carried at or near the surface of the ice 

 sheet. Large areas of the till plains are nearly stone free at the 

 surface. 



It is characteristic of the Wisconsin stage of glaeiation that the 

 thickest and most hilly areas of morainal deposition were formed 

 between the lobes of the glacier invading the Lake region. Along 

 such interlobate lines both lobes of the glacier deposited the included 

 earthy and stony material as the ice melted. Along such lines also 

 the action of water upon the glacial material was pronounced and 

 many of the interlobate moraines consist of true unstratified till, of 

 hillocks and ridges of water-washed and partly assorted gravel and 

 stone, and of nearly level sandy areas. The associated hillocks, 

 ridges, basins, and hollows, largely formed from stratified material, 

 are commonly called kames. They differ from the morainal areas 

 chiefly in the predominance of stratified drift and to some extent in 

 the presence of kettle-shaped hollows inclosed between sharp ridges 

 and knolls. A characteristic cut in such stony and sandy material 

 is shown in Plate II, figure 1. 



The melting of the glacier was accompanied by a greatly swollen 

 condition of the streams which issued from the ice front. These 

 streams carried large quantities of gravel, sand, and silt southward 

 to the uncovered drainageways of the larger rivers. As a result the 

 lower courses of the majority of the streams from the glaciated ter- 

 ritory are bordered by terraces of water sorted and washed material 

 not included in the Miami series of soils. In some instances partial 

 readvances of the ice sheet covered such stratified deposits with a 

 later sheet of till, and there are large and small areas of the Miami 

 soils within the till plains which are underlain at various depths 

 with stratified deposits of such origin. 



In many instances the glacial drainage issuing from the inter- 

 lobate moraines carried out sorted material which was deposited 

 over broad frontal plains in the form of out wash aprons and terraces 

 along drainageways. While these areas do not give rise to soils of 

 the Miami series, they are intimately^ associated with them, occupy- 

 ing extensive level tracts between the ridged moraine areas and 

 bordering on the undulating or nearly level till plains. It is 

 natural that considerable areas in southern and southwestern Michi- 

 gan should be formed by such deposits, since the drainage from the 

 interlobate region between the Saginaw and the Erie lobes and 

 between the Saginaw and Lake Michigan lobes escaped to the south- 

 west across the Michigan-Indiana line. This condition also gave 

 rise to extensive upland areas where the glacial deposits are so evi- 



