226 PLEISTOCENE OF INDIANA AND MICHIGAN. 



not attempt to map them completely but simply determined the general extent and approxi- 

 mate level of each lake and its probable course of discharge to the next. When topographic 

 maps have beeD made it will not be difficult to represent these lakes more definitely. 



Lake on the lower Kalamazoo. — The glacial lake that occupied the lower Kalamazoo covered 

 much of the space between the Lake Border and Valparaiso morainic systems from Rabbit River 

 southward into the Black River drainage basin in northwestern Van Buren County. Its northern 

 limits were determined by the strong morainic ridge that lies north of Rabbit River in northern 

 Allegan County. Several lines of evidence unite in fixing its altitude at about 680 feet; the 

 sandy plain that now occupies its bed is definitely limited on the east and south by the Valpa- 

 raiso system at an altitude of very nearly 680 feet, as shown by the railway elevations at Dunning 

 and at Columbia and Grand Junction, and is bordered by a well-defined terrace of the Kala- 

 mazoo Valley at about 680 feet; further, the altitude of an outwash apron of the Lake Border 

 morainic system near Fennville is about 680 feet. This lake appears to have at first discharged 

 southward to Paw Paw River past Breedsville and Bangor and through swampy channels 

 near McDonald, coming to the Paw Paw Valley near Hartford; but when the ice had shrunk 

 back to Covert Ridge l the lake may have discharged along the eastern edge of the ridge, which 

 is bordered by a somewhat sandy plain. The relative elevations of the two courses of discharge 

 are not known, but they certainly differ by only a few feet. 



The pitted gravel plain near Fennville occupies an area of several square miles along the 

 outer border of Covert Ridge. Close to the ridge basins are conspicuous and the gravel is of 

 medium coarseness ; a mile or two outside the basins disappear and the gravel gives place to sand. 

 The border of the glacial lake probably lay along the eastern edge of the basins. Small strips 

 of gravel plain, preserved along the south edge of the moraine north of Rabbit River, he at an 

 altitude high enough to have been deposited outside of or above the edge of the glacial lake. 

 The material is decidedly coarser than that on the sandy plain to the south. 



Lake in lower St. Joseph and Paw Paw valleys. — The next lake in the series stands in the 

 lower St. Joseph and Paw Paw valleys in Berrien County. This lake appears to have extended 

 up the Paw Paw Valley about to Hartford and to have there received the drainage of the lake 

 in the Kalamazoo basin. It filled in the narrow space between the Lake Border and Valparaiso 

 systems from near Hartford southward about to Baroda, 10 miles south of St. Joseph, and 

 crossed the divide between the St. Joseph and Galien river systems through a swamp south of 

 Baroda. The altitude of this lake appears to have been about 20 feet lower than that of the 

 lake in the Kalamazoo basin, as determined by the level of the outlet near Baroda and by a 

 terrace on the St. Joseph near Berrien Springs which seems to be correlated with this lake and 

 which stands about 660 feet above sea level. The outlet of this lake cuts into the edge of the 

 part of the Valparaiso system directly east of Baroda and appears also to have cut shghtly 

 along the east edge of the outer ridge of the Lake Border morainic system west of Baroda. 

 These cut bariks are, by hand level from Baroda, 20 feet higher than the station, or 660 feet. 

 The area occupied by the lake in the Paw Paw and St. Joseph valleys has a coating of gravel and 

 sand several feet in depth, :n places overlying a pebbleless silt. Whether the silt is to be cor- 

 related with this small lake and the overlying gravel and sand with Lake Chicago which after- 

 ward came into the same district can not at present be stated. Probably, however, the streams 

 draining into the larger and longer-lived lake contributed a considerable part of the sand and 

 gravel. 



Lake on Galien River. — A pool 1 to 3 miles wide appears to have occupied the lower courses 

 of the tributaries of Galien River in southern Berrien County, extending from the vicinity of 

 New Troy southward about to the State fine and covering the western part of the space between 

 the outer ridge of the Lake Border morainic system and the inner edge of the Valparaiso system. 

 The soil in the areas supposed to have been covered by this pool is more sandy than that on a 

 till plain lying nearer the inner border of the Valparaiso morainic system. After the ice had 

 withdrawn from the outer ridge to the second ridge this pool spread into the narrow strip lying 



1 This name was applied in Mon. TJ. S. Geol. Survey, vol. 38, to the principal till ridge of the Lake Border morainic system. 



