188 PLEISTOCENE OF INDIANA AND MICHIGAN. 



Big Rapids and Rodney. North of this is another sandy tract that has its northeastern limits 

 near Chippewa Lake and its southeastern limits near Rodney; it is less elevated than the 

 sandy tract in Austin Township and in places has the general features of a pitted gravel plain. 

 These sandy tracts have very few surface bowlders compared with the number on the bordering 

 till tracts. A large section of the moraine lying along a line running from Big Rapids past the 

 north end of Chippewa Lake to Barry ton and extending on the north to Muskegon River has 

 a preponderance of till but includes small areas of sandy and gravelly drift. 



North of Muskegon River, in central Osceola County, an area of about 75 to 100 square 

 miles of very sandy and elevated moraine is entirely surrounded by lower tracts with a some- 

 what clayey drift. In the northern part of Osceola County, on the highest land of the southern 

 peninsula, considerable till is present, the sandiest tracts being in the relatively low districts 

 in the northwestern and northeastern parts of the county. 



Along the southern edge of the southeastern township of Wexford County and in much of 

 the southwestern township of Missaukee County clayey drift is present, but in the district 

 immediately east of Cadillac at the extreme northern point of the interlobate moraine an area 

 of several square miles is very sandy. 



BOWLDERS. 



Bowlders, which are almost or wholly lacking on other sandy portions of the moraine, 

 thickly strew the sandy district in central Osceola County. They are less numerous on the 

 sandy strip in eastern Lake and eastern Newaygo counties than they are on the clayey tracts 

 to the east, but they are by no means rare in either place. Except on the small sandy areas 

 they average several thousand to the square mile on the prominent part of the morainic system 

 from Cadillac southward to southern Mecosta County. In the southern part they are generally 

 concentrated in the vicinity of the sharper ridges and knolls and are relatively scarce on the 

 gently undulating tracts, being most prevalent in western Barry County and especially in the 

 district southwest of Hastings, where they are almost as numerous as in the prominent northern 



portion. 



GLACIAL DRAINAGE. 



The drainage from the reentrant between the Lake Michigan and Saginaw lobes at the 

 junction of the outer moraine of the Kalamazoo system and its correlative moraine in the 

 Saginaw lobe was southward from southern Barry County across central Kalamazoo County 

 to St. Joseph River below Centerville. It passed directly across the present course of Kalamazoo 

 River east of Kalamazoo. Its gravel plain has an altitude of nearly 1,000 feet at its head near 

 Prairieville in Barry County, but descends to less than 900 feet at the bluff of Kalamazoo River, 

 to about 800 feet at the place where it enters Indiana a few miles southwest of Centerville, and 

 to about 720 feet at the bend of St. Joseph River near South Bend, Ind. From South Bend 

 the discharge was down the Kankakee to the Illinois and thence to the Mississippi and the 

 Gulf of Mexico. 



From the reentrant between the two ice lobes in northeastern Allegan County the drainage 

 was southward along the Gun River valley to the Kalamazoo and thence either to South Bend 

 through the low tract west of the Kalamazoo morainic system or down the Paw Paw Valley to a 

 glacial lake held in front of the ice near the mouths of Paw Paw and St. Joseph rivers. It is 

 probable that the former course was in operation until after the ice had withdrawn from this 

 gravel plain, and that the latter course was utilized by the later glacial drainage that came 

 down the Thornapple Valley. 



From the reentrant between the two ice lobes at the bend of Grand River north of Grand 

 Rapids the drainage was southward along a well-defined valley that led past Ross and on through 

 northern Allegan County. It appears to have continued for a time southward to the Kalamazoo 

 Valley at Allegan, but on the withdrawal of the Lake Michigan ice lobe from a moraine north 

 of Allegan it shifted to the west side of the moraine and made its way southward along the 

 edge of the receding ice to the head of Lake Michigan and thence to Desplaines, Illinois, and 

 Mississippi rivers. 



