138 FBOCEEBINGS OF THE NATIONAL MUSEUM. vol.xxii. 



PISIDIUM COMPRESSUM Prime. 



Heron Lake; a single dead valve. 



PISIDIUM VARIABILE Prime. 



Eagle Lake (Oat. No. 1^3903, U.S.KM.); numerous odd valves. 



It is presumable that these lakes contain many sj)ecies not mentioned 

 above. It should be borne in mind that no attempt was made by Mr. 

 Bailey to make an exhaustive collection of the molluscan life in these 

 bodies of water ; he simply collected such material as came readily to 

 his hand without interfering with his special work. 



