THE VALPAEAISO MOEAINIC SYSTEM. 379 



the border of the Kankakee marsh and borders this marsh somewhat closely 

 across Lake County, Indiana, Whatever outwash there may have been 

 along the border -of the moraine in western Porter and in Lake County, has 

 been removed by currents of water passing down the Kankakee. 



Numerous references have been made to the gravel outwash on the 

 east border of the Valparaiso morainic system in southwestern Michigan, 

 and the relation of this outwash to the Valparaiso morainic system has been 

 set forth in the discussion of the border between the Lake Michigan and 

 Saginaw lobes. The line of escape for the small bodies of water in which 

 this outwash was formed have been only partially worked out. It seems 

 highly probable that the escape was southward into the Kankakee from the 

 Dowagiac Valley, and possibly this line was open for waters collected in the 

 headwater portion of the Pawpaw drainage basin. Drainage may have 

 been greatly obstructed at times by the Saginaw lobe, and the height to 

 which water rose was probably greatly influenced by the oscillations of the 

 ice margin. The great amount of sandy and gravelly material formed 

 along the elevated eastern border of the Valparaiso morainic system appar- 

 ently indicates the action of water at heights of 300 feet or more above the 

 level of Lake Michigan, or about 900 feet above tide. If this height were 

 attained by the waters held between the Saginaw and Lake Michigan ice 

 lobes in Allegan and Van Buren counties, they might easily find escape 

 southward to the Kankakee Basin whenever the ice lobes afforded an oppor- 

 tunity for escape, for the head of the Kankakee Basin stands only a little 

 more than 700 feet above tide. There does not appear to have been a uni- 

 form filling along the line of the supposed southward discharge. On the 

 contrary the gravel plains appear to be rather in the form of small deltas 

 extending out for a few miles where the slopes favored drainage, but absent 

 along the portion of the morainic border where the slopes are unfavorable 

 to such drainage. The gravel outwash appears to be nearly constant along 

 the Dowagiac Valley throughout its entire length, a feature which seems to 

 favor strongly the view that southward discharge was seldom interrupted, 

 but on the Pawpaw and Kalamazoo tributaries, as already noted, the out- 

 wash is more restricted. 



Upon the whole the Valparaiso morainic system displays a coarser out- 

 wash and gives evidence of more vigorous drainage than has been found on 

 any of the morainic systems of the early Wisconsin series, though it is 

 closely rivaled by the drainage from the Bloomington system. 



