ENGLACIAL DRIFT OF THE MISSISSIPPI BASIN. 55 



and some others of the Saginaw glacial lobe. These are so 

 associated with the inter -tangled morainic phenomena of that 

 region as not to admit of convenient and brief description in 

 their genetic relationships. 



The well -defined tracts have a most significant distribution. 

 The first part described is associated with the terminal moraine 

 that marked the margin of a lobe of ice that moved westward 

 along the axis of the Iroquois basin to a point a few miles beyond 

 the Indiana-Illinois line. The portion that runs southward to 

 the Wabash is associated with the moraine that follows the same 

 course, and runs at right angles over the older moraines of the 

 Lake Michigan lobe. The tract in Tippecanoe and Montgomery 

 counties, that in south Marion county, and that in Henry and Ran- 

 dolph counties, in the eastern part of the state, are associated 

 with the terminal moraines that form a broad loop with the West 

 White river basin lying in its axis. In western Ohio the belt is 

 intimately associated with a moraine that bordered the Miami 

 lobe of the ice sheet, and the south -trending portion in eastern 

 Logan and Champaign counties lies on the western margin of 

 the Scioto lobe. 



The relationship of these tracts to terminal moraines is very 

 clear and specific. They constitute marginal phenomena of the 

 ancient ice sheet. Their distribution completely excludes their 

 reference to floating ice, for they not onl}' undulate over the 

 surface utterly negligent of any horizontal distribution, but they 

 are disposed in loops in crossing the basins of the region, and the 

 convexities of these loops are turned down stream. These basins 

 for the most part open out in southerly or westerly directions 

 which makes it improbable that ice - bearing bodies of water occu- 

 pied them. But if this were not fatal, certainly the fact that the 

 convexities of the boulder belts are turned down stream and cross 

 the centers of the basins is precisely contrary to the distribution 

 they must have assumed if they were due to floating ice in bodies 

 of water occupying the basins. I hold it, therefore, to be beyond 

 rational question that these tracts were deposited as we find 

 them by the margins of the glacial lobes that invaded the region. 



