24 



MUSSEL FAUNA OF THE KANKaKEE BASIN. 



depth is 32 feet. The greater part of the shore line is low and 

 marshy, and the water is filled with a dense growth of reeds and 

 rushes. The bottom is sand or blue and sticky clay, interspersed with 

 extensive muck beds, the latter giving rise to a luxuriant growth of 

 aquatic vegetation. The sand and clay are also covered with algae, 

 among which is Char a. Potamogeton is also common. In fact the 

 lake flora is richly developed at the expense of the fauna. At present 

 the lake has no outlet or natural inlet, but is fed entirely by springs. 

 The old outlet, however, now so filled that water runs through it only 

 occasionally, was to the west, emptying into the Kankakee about 3 

 miles below station 16. Dwarfed L. luteolus were fairly common in 

 the gravelly sand close to the shore, and there was a large bed of 

 them around a point which juts out into the lake from the eastern 

 shore. Cranberry Point. A few A. grandis were also found. Both 

 species were infested with Atax parasites, but not in large numbers, 

 and in addition Cotylaspis and the distomid of Osborn were present 

 in A. grandis. This lake had been examined in 1906, and a number 

 of Anodontas obtained near the ice houses and Lampsilis luteolus on 

 the opposite shore. 



Station 17. Kankakee River ^ Riverside^ Ind. — On the way down 

 from English Lake to Riverside small piles of mussel shells that had 

 been left by pearlers were frequently found. Here the mussels have 

 fully reestablished themselves in the dredged portion of the river, 

 and the steep banks just under the water were well lined with Z. 

 luteolus. 



Just above Riverside the dredged ridge along the north bank of 

 the river held back a small pond covered with Euglena in a portion 

 of the old channel. This was nearly filled with soft mud and con- 

 tained but few mussels, though there were plenty of dead shells along 

 the bank. On this stretch of river there was a marked increase in 

 the number of ligamentinus and ventricosus. All the shells found 

 were large and of excellent quality. 



Station 18. Burrow's Camp to Baum^s Bridge. — The dredged 

 portion of the river stopped at the last station and we now entered 

 the genuine Kankakee swamps. The sides of the river were low and 

 boggy but heavily wooded for a short distance back from shore. The 

 bottom we found to be firmly packed sand, admirable for wading, 

 and there was a current of 4 miles an hour. 



Mussels were plentiful along the shore v>^herever the bottom could 

 be seen, and we waded often enough to show that they continued into 

 the deeper water. There were occasional piles on the banks, left by 

 fishermen and pearlers, and in one of the shells thus left a small pearl 

 was found. But only one of the live luteolus yielded pearls, a much 

 smaller percentage than farther up the river. 



