MUSSEL FAUNA OF THE KANKAKEE BASIN. 5 



We thus have a basin surrounded by glacial moraines and every- 

 where covered with a heavy mantle of glacial drift or till, so thick 

 that not a single outcrop of surface rocks is known to occur within 

 its limits," even in the bed of the river or any of its tributaries. Con- 

 sequently, there are no rocky bottoms with alternating riffles and 

 quiet reaches, but everywhere a uniform current and labyrinthine 

 windings. The river itself is noted for its low banks and the crooked- 

 ness of its channel. It rises in a marsh about 3 miles southwest of 

 South Bend in St. Joseph County, Ind., flows southwesterly through 

 that county to the Laporte County line, from which point it forms 

 the boundary between the counties of Laporte, Porter, and Lake on 

 the north, and St. Joseph, Starke, Jasper, and Newton on the south. 

 At about the center of the Starke County line it receives the Yellow 

 River as a tributary from the east. Crossing the State line between 

 Lake and Newton Counties, it flows south of west to the town of 

 Waldron, 111., where it is joined by the Iroquois River from the south. 

 Thence it flows northwesterly to the northeastern corner of Grundy 

 County, where it joins the Des Plaines, coming from the north, and 

 the two form the Illinois River. 



The Yellow River, its principal eastern tributary, rises in three 

 forks, north, middle, and south, in the southeastern corner of St. 

 Joseph County, Ind., the southwestern corner of Elkhart County, 

 and the northwestern corner of Kosciuszko County, respectively. 



The north and middle forks unite near Bremen in Marshall 

 County, and flow directly south until opposite Plymouth, the county 

 seat. Here they are joined by the south fork, and the river turns 

 westward through Plymouth, then south for about 5 miles, and then 

 westward again through the remainder of Marshall and the whole 

 of Starke County, entering the Kankakee at about the center of what 

 was formerly English Lake. 



The Iroquois River, the only other tributary of any size, arises in 

 several creeks in the southeastern portion of Jasper County, Ind., 

 flows a little south of west across Jasper and Newton Counties, cut- 

 ting the State line 6 miles north of the southern boundary of Newton 

 County. It then flows west through Iroquois County^ 111., as far as 

 Watseka, the county seat, where it receives Sugar Creek from the 

 south. The two then flow northwest about 5 miles to a junction 

 with Spring Creek, also from the south. There the river turns 

 almost due north and crosses the remainder of Iroquois County and 

 into Kankakee County, where it empties into the Kankakee River a 

 mile west of the town of Waldron. The Yellow River is about 65 

 miles, the Iroquois 100 miles, and the Kankakee 300 miles in length. 

 The banks of the Yellow and Iroquois Rivers, and those of the 

 Kankakee River in Illinois, are high and solid and in many places 

 well wooded, and the adjacent country is of the usual prairie type. 



« That is, in the State cf Indiana. 

 9275°— 13 11 



