MAIN MORAINIC SYSTEM IN THE GRAND RIVER LOBE. 451 



In Columbiana and Mahoning counties, Ohio, the drift knolls are 

 grouped irregularly, some sections having a very hummocky surface, while 

 others have only scattering drift knolls. The outer border of the moraine 

 was not studied sufficiently to warrant a description of the terraces con- 

 nected with it. It was noted, however, that in the so-called "fringe" Wright 

 has, in portions of Columbiana County, included moraine hillocks of as 

 characteristic a type as those in the main moraine, from which it appears 

 that his mapping of the "fringe" encroaches somewhat on the moraine. For 

 example, at Bayard and east from there toward East Rochester the valley 

 of Little Sandy Creek contains numerous sharp drift knolls and ridges, 10 

 to 15 feet high, among which are sharply defined basins, the contours of 

 the moraine hillocks here being fully as sharp as anywhere in the belt. 

 The sharpness of contour renders it improbable that these knolls are much 

 older than the main moraine, and the topography is such as to make them 

 a part of the moraine rather than of the outlying drift. 



The moraine is well developed from Bayard northward nearly'- to 

 Alliance, both in the lowland tract which the Cleveland and Pittsburg 

 Railway utilizes and the highlands each side, and no perceptible break 

 occurs to warrant its being distinctly separated from the main belt. A few 

 miles to the west, however, the outer portion becomes distinctly separated 

 by a nearly plane interval 2 or 3 miles wide. The outer belt carries low 

 drift knolls 5 to 15 feet high, among which are shallow basins of fresh 

 appearance. Bowlders are very numerous. The main belt from the 

 meridian of Bayard northwestward to the interlobate moraine contains 

 knolls and ridges 20 to 40 feet high, and shows an increasing sharpness 

 upon approaching the interlobate tract. 



The interlobate tract has for 2 or 3 miles eastward from the Cleveland 

 and Canton Railway (which it is thoug'ht may follow nearly the border 

 between the glacial lobes) clusters of knolls and ridges 15 to 50 feet or 

 more in height, alternating with or surrounding basins and marshy tracts 

 occupied by lakes or ponds. Farther east a gentle swell-and-sag topography 

 is found. In the vicinity of Ravenna and north from there through Shalers- 

 ville Township, Portage County, there are large gravelh^ knolls 30 to 50 

 feet or more in height, arranged usually in groups. There are also lakes 

 and marshes of considerable extent, some of the larger ones having an area 

 of 2 or 3 square miles. South of Ravenna the marshes and lakelets are 



