446 Annals of the Carnegie Museum. 



33. Musculium florissantense (Cockerel!). 



Sphariinn flcnissantense T. D. A. Cockerell, Bull. Am. Mus. Nat. Hist., XXII, 

 Dec, 1906, p. 462, fig. 5. 



Fossil. — Miocene of Florissant, Colorado. 



Genus EuPERA Bourguignat. 

 Limosina Clessin. 



1. Eupera cubensis (Prime). 

 SphcBrium cubense Prime, Mon. Corb., p. 58. 



Habitat. — Florida. 



2. Eupera singleyi (Pilsbry). 



Spharium {Limosina) singleyi Pilsbry, Proc. Acad. Nat. Sci. Philada., 1889, p. 88, 

 PI. Ill, figs. 14, 15. 

 Habitat. — Texas, Louisiana. (Near E. cubensis.) 



Genus PisiDiUM C. Pfeiffer. 



1. Pisidium virginicum (Gmelin). 



Tellina virginica Gmelin, Syst. Nat., VI, 1772, p. 3236. 

 Pisidium virginicum Prime, Mon. Corb., 1865, p. 61. 



Habitat. — East of the Rocky Mountains, north to Yukon and 

 Alaska. 



Fossil. — New York, Michigan, Illinois. 



2. Pisidium amnicum (M tiller). 



Tellina amyiica Muller, Verm. Hist., II, 1774, p. 205. 



Pisidium. amnicum B. B. Woodward, British Pisid., 1913, p. 16, figs. 



Pisidium bakeri Pilsbry, listed by F. C. Baker in Nautilu.";, XIV, p. 71. 



Habitat. — Lake Ontario, probably introduced from Europe. 



3. Pisidium idahoense Roper. 



Pisidium idahoense Roper, Nautilus, IV, 1890, p. 35. 



Habitat. — Idaho, Washington to Yukon, Lake Michigan, Prince 

 Edward Island. 



4. Pisidium idahoense indianense Stcrki. 



Pisidium idahoense var. indianense Sterki, Nautilus, XIX, 1905, p. 80. 

 Habitat. — Lake Maxinkuckcc, Indiana. 



