24 MUSSELS OF CENTKAL AND NORTHEEN MINNESOTA. 



The lake is fed by numerous large springs in addition to several 

 inlet streams, wMcli drain the surrounding country. The lake con- 

 tains an abundance of sunfish, perch, crappies, wall-eyes, and bass. 

 On the northwest shore of the lake, within the city limits of Glen wood, 

 there is a State fish hatchery under the supervision of Supt. J. A. 

 Pinkerton. The water for the hatchery comes from one of the large 

 springs that feed the lake, while a series of fishponds or aquaria are 

 built in the lake along the shore. The lake was found to contain a 

 great many mussels, which, however, possess no commercial value. 

 These include the fat mucket (luteola), which is much dwarfed and 

 thin-shelled, with an epidermis which erodes easily and turns dead 

 white on exposure, three species of Anodonta, imbecillis, pepiniana, 

 and henedictensis, and Anodontoides. The profusion of these mussels 

 and the rapidity of their development show that there is an abun- 

 dance of food in the lake. 



We find, therefore, that the temperature and depth of the water, 

 the kind of bottom, the presence of numerous shallow sand bars, 

 the freedom from aquatic vegetation, and the abundance of suitable 

 food combine to make this lake an ideal one for the artificial propa- 

 gation of mussels, particularly the Lampsilis group. And, as if to 

 complete the requisites, here is a fish hatchery, in whose interests 

 hundreds of bass and wall-eyes are seined out of the lake every 

 spring. Along with the game fish which are used by the hatchery 

 there are always taken in the seine a large number of sunfish and 

 yellow perch which are simply thrown back into the lake. What 

 could be simpler than to supply the hatchery with gravid mussels of 

 some valuable commercial species and impregnate these sunfish and 

 perch with the glochidia before they are returned to the lake ? Mani- 

 festly this is a rare opportunity for testing the possibilities of mussel 

 propagation with almost no additional expense. The importance of 

 such practical experimentation under the direction of skilled work- 

 men can hardly be overestimated. 



While in Glenwood we were rendered great assistance and were 

 shown many courtesies by the officials at the hatchery. One of 

 them, Mr. John Dahl, took us around the lake, gave us many data, 

 and explained the local conditions, with which he was thoroughly 

 conversant. Our sincere thanks are hereby returned to him and to 

 the superintendent for these and many other favors. 



Lake Osakis, situated close to Osakis, in the southwestern corner 

 of Todd County, is 10 miles long and 3 miles wide. The bottom, the 

 depth of the water, the presence of sand bars, and the freedom from 

 aquatic vegetation correspond exactly to those at Lake Minnewaska. 

 This lake also has no outlet except at very high water, and is a typical 

 shallow lake, such as are common in glaciated regions. 



