Catalogue Recently -Described Mollusca 189 



MuscuLiuM errans (Lewis). 

 Cyclas errans Lewis, Ubi ? 



I,ewis (Pr. A. N. S. P., 1872, p. 105) says that he "proposed" this spe- 

 cies a number of years before, but that Prime considered it a synonym of 

 rosaceum. That from further study, he is "induced" to reclaim his species. 

 I have been unable to find any other reference to the species. 



Genus PISIDIUAI C. Pfeiffer, 1821. 



The use of Corncocyclas Fer. for this genus proposed by Dall (30, p. 7 

 and 29, p. 1459) is disputed by Woodward (165, p. 367 and 166, p. i) and 

 has not been followed by Sterki (125, p. 473) and until the question has 

 been definitely settled, it seems preferable to use the name that has been in 

 common use for so many years. 



PisiDiUM rorEalE Westerlund. 



Pisidiiiin horeale Westerlund, Kongl. Sv. Vet. Ak. Forh., 1877. P- /O. fig. 27,. 



Type locality : Lusino, Siberia. ? Port Clarence, Alaska. 



PisiDiUM calieornicum CNcwcomb ?). 



Listed by Berry (Naut.. XXIIL 1909. p. 79) from Blufif Lake, San Ber- 

 nardino Co., Cal. I have not been al)le to find any other reference to it. 



PiRIDIUM COMPRESSUM LIMNTCOLUM Sterki. 



Pisidiiini comf^ressnin liinnicoluni Sterki, Naut., XIX, 1905, p. 8[. 

 Type locality : Fox River, Wis. 



PiSIDTUM COMPRESSUM SMITHII Sterki. 



Pisidiiiin comprcssuni siiiithii Sterki, X^aut., XIX, 1905, p. 83. 

 Type localitv : Shoal Creek. Ala. 



PiSTDiUM NOVEPORACENSE PROCLivE Sterki. 



Pisidiiiin novehoraccvsc proclivc Sterki, X'aut. XIX, 1906, p. 119. 



Type locality : X^ew Philadelphia, O. 



PisiDiuM OPTUSALE C. Pfeififer. 



This European species has been listed from near Lake lames, Steuben 

 Co., Ind. by Sterki (Naut, XVII, 1903, p. 43). 



PisiDiUM siPiRicuM Westerlund. 



Pisidiiiin sibiricinn Westerlund X'achr. Blatt. Gess. 1876, p. 103; Clessin, 



Con. Cab.. Cycladeen, 1877, p. 66, .pi. AMI, figs. 15-17. 

 Type locality: Yenesei River, Siberia. 



? Port Clarence, Alaska according to Dall (7,2, p. 144). Ball's reference 

 for this species in K. Svenska Vet. Ak. Forh. is erroneous. It should be 

 P- ^V^ fi?- 2T, not p. 70, fig. 23. 



