XXXVI FISHES OF ILLINOIS 



to about the average high-water level. A canal, 100 miles 

 long, called the Illinois and Michigan canal, starts from Lake 

 Michigan at Chicago, and, cutting through the low summit, 

 enters the Des Plaines valley. It crosses the river at Joliet, 

 and then follows along the right bank of this river and of the 

 Illinois to Peru, where it enters the latter river. 



The principal branch of the Des Plaines is the Dupage 

 River, which rises in southern Lake county, and, flowing south- 

 ward, empties into the Des Plaines only 4 miles above its junction 

 with the Kankakee. It is about 50 miles in length, and drains 

 about 366 square miles of intermorainic country. It is a swiftly 

 moving stream, the last 11 miles of its course having a fall of 

 80 feet. Its banks are generally low and rolling. 



KANKAKEE RIVER 



Kankakee River rises in a large marsh about three miles 

 southwest of South Bend, St. Joseph county, Ind. It flows in 

 a southwesterly direction to the southern boundary line of 

 La Porte county, and then more westerly, crossing the Indiana- 

 Illinois state-line in southern Lake county, Indiana. It then 

 flows a little south of west to within a few miles of Kankakee, 

 where it receives the Iroquois from the south. Thence it pro- 

 ceeds almost due northwest to near the northeast corner of 

 Grundy county, where it unites with the Des Plaines to form 

 the Illinois. 



The Kankakee is about 140 miles long; 85 miles lying in 

 Indiana. Its drainage basin covers about 5,300 square miles, 

 of which 3,140 square miles are in Indiana. This basin has its 

 northern limits in the Valparaiso morainic system, and all of 

 the important northern tributaries find their sources in the 

 same system. Its southern limits, in the portion below the 

 mouth of the Iroquois, are found in the Marseilles moraine. 

 The Iroquois rises in a somewhat distinct area, draining basins 

 south of the Iroquois and Marseilles moraines and passing 

 through a gap in the latter moraine to enter the Kankakee. 

 The eastern limits of the Kankakee basin are mainlv in the 

 Maxinkuckee moraine of the Saginaw lobe. 



Probably the whole of the Kankakee basin was formerly an 

 old lake, called now by geologists Lake Kankakee, and, at the 

 same time that the old ''Chicago outlet" was full, it may have 

 been a line of discharge for the St. Joseph River, now a tribu- 

 tary to Lake Michigan, carrying also a large amount of glacial 

 drainage from the Saginaw and Lake Michigan lobes. 



