FRESH-WATER MUSSELS. IO9 



of the mussels. In Lake Maxinkuckee, Evemiann and Clark (1918, p. 255) say : "Mussels 

 are to be found almost anywhere in water 2 to 5 or 6 feet deep where the bottom is 

 more or less sandy or marly." Headlee (1906, p. 306) found that the mussel zone 

 generally extended from the shore line to where the bottom changes from sand, gravel, 

 or marl to very soft mud, a region in Winona Lake covered by from 4 inches to 9 feet 

 of water. He did find, however, some mussels on sandy_ bottom in 22 feet of water. 

 He made some experiments in retaining mussels at various depths and in a crate placed 

 in 85 feet of water; only i of 10 specimens died in six days of exposure. After 12 days 

 several specimens were found badly choked with mud. 



In Lake Pepin mussels are plentifully found at depths ranging from 8 to 20 feet, 

 but the majority are taken at depths ranging from 1 2 to 1 8 feet. Relative to the juvenile 

 mussels, out of a total of 1,397 collected in 1914, 1,283, or 9i-8 per cent, were taken ata 

 depth of 3 to 8 feet; 2.6 per cent at 8 to 12 feet; 2.3 per cent at 12 to 16 feet; 0.4 per 

 cent at 16 to 20 feet; and 2.9 per cent at 20 to 25 feet. A . imhecillis was the only juvenile 

 found in any abundance at a depth greater than 15 feet, and 41 of the 79 individuals of 

 this species collected were taken at 25 feet (Shira, report in manuscript). 



A marked distribution with regard to depth has been observed in the artificial 

 ponds at Fairport, Iowa. Here the species, Lampsilis luteola, is seldom found below a 

 depth of 3 feet. When held in crates below this depth it does not thrive, although in its 

 natural habitat, Lake Pepin, this species is abundant at a depth of 8 to 20 feet and has 

 been taken at a depth of 25 feet. 



In rivers and smaller streams mussels seem to be found commonly at lesser depths 

 than in lakes, but unfortunately we have very few reports of observations in the deeper 

 parts of large rivers. In the Illinois River, Danglade (1914) mentions a small bed 2 to 3 

 acres in extent above the mouth of Spoon River, where the bottom was of mud, the 

 current about 2 miles per hour, and the depth of water 8 feet. At Chillicothe he found 

 a good bed at a depth of 1 2 to 1 5 feet. The survey of Andalusia Chute, Mississippi River 

 (Howard, report in preparation), carried on during relatively high-water stages in 1915, 

 revealed no mussels in the deeper portion of the river over 12 feet in depth, and the 

 greater number of mussels were found at depths less than 10 feet. Local informants at 

 Madison, Ark., stated that the niggerhead, Quadrula ebenus, was found in water 20 to 50 

 feet deep; it was also said that in flood season it was captured from a depth of 75 feet. 

 There has been no opportunity, however, to verify these statements. 



With regard to a collection of 1 83 juveniles of the Quadrula group from 1 2 stations 

 in the Mississippi River, Howard (191 4, p. 34) reported depths from o to 8 feet. Wilson 

 and Clark (1914) reported a rich find (19 species) in the Rock Castle River off the Cum- 

 berland, in water having a maximum depth of 1)4 feet. In the Grand River, Mich., 

 the senior author has found mussels (muckets, Lampsilis ligamentina, three-ridge, 

 Quadrula undulata, and others) in conspicuous abundance in swift water less than a foot 

 in depth. Boepple (Boepple and Coker, 1912) found mussels abundant and of fine 

 commercial quality in water from i to 3 feet in depth in the Holston and Clinch Rivers 

 of Tennessee. In Caddo Lake, Tex., Shira (1913) found an abundance of mussels in 

 4 to 8 inches of water, and in many places there was scarcely enough water to cover the 

 shells. This lake was very shallow over large areas. In fact, mussels are frequently 

 found in very shallow water where the conditions of the bed of the stream and other 

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