I04 Bryant Wai^ker 



Pl.ANORBIS TRIVOI.VIS Say. 



Includes snbcrenatiis Cpr., with oregonensis Tryon, occidentalis Cooper, 

 and tumens Cooper, non Cpr., as synonyms and probably hornii Tryon ac- 

 cording to Dall (32, p. 89). .Pilsbry also (95, p. 65) lists hornii as a variety. 



PlvANORBlS TL'IVOIA'US BINN^YI Tryon. 



Planorhis corpulentus Gould, U. S. Expl. Exp., 1852, p. 114, fig. 130; Hal- 

 deman, Mon., 1844, p. 19, pi. Ill, figs. 7-9 ; W. G. Binney, L. & F. W. 

 Shells, pt. II, 1865, p. 114, figs. 191-2; Sowerby, Con. Icon., 1877, Sp. 

 4, pi, I, fig. 4 ; pi. X, fig. 4b. 



Planorhis hinneyi Tryon, Am. J. of Con., Ill, 1867, p. 197. 



Type locality : West Coast. 



Pi^ANOEiris uMBfLicATEixus Cockcrell. 



Planorhis mahilicatus Taylor, J. of Con., IV, 1885, p. 351, text-fig. non 



Miiller (1774). 

 Planorhis umbilicatclhis Cockerell, Con. Ex., 1885, II, p. 68. 

 Type locahty : Brandon and Birtle, Manitoba. Ranges from New York 



to South Dakota. See also Vanatta (137, p. 117)- 



Pi^ANORBTS ve:rmtcui,aris Gould. 



Is referred to parvus by Vanatta (136, p. 55), but is considered dis- 

 tinct by Dall (32, p. 95). 



Genus SEGMENTINA Fleming, 1817. 



Subgenus PLANORBULA Haldeman, 1842. ■ 

 Segmdntina armigera (Say). 



Dr. Pilsbry informs me that he has seen the type of Planorhis lantiis 

 H. Ads. and that it is a young specimen of this species. 



Segmentina armigera campestris Dawson. 



Segmentina armigera campestris Dawson, Rep. Brit. N. A. Boundary Com., 



1875, p. 349. 

 Type locality : Red River Valley, Canada. 



Segmentina ciiristyi Dall. 



Segmentina christyi Dall, Rep. Harriman Exp. XIII, 1905, p. 99, pi. 11, 

 figs. lO-II. 



Type locality : High Bluff, Manitoba ; Fort Smith, Mackenzie River. Re- 

 ported from South Dakota by Walker (151, p. 11). 



Segmentina crassilaeris Walker. 



Segmentina crassilahris Walker, Naut., XX, 1907, p. 122, pi. 7, figs. 4-6. 

 Type locality: Hamtramck, Wayne Co., Mich. 



