98 Brvant Walkkr 



Planorhis commutatus "Dunker" Sowerby. 



I'lanorbis cojiumitatus Sowerby, Con. Icon., Planorbis, 1876, Sp. 63, \)\. 8, 



fig- 63. 

 Type locality : North America. 



Planorbis corpulkntus Say. 



Is a valid species. See Walker 144, p. 133. The citation of this 

 species from Florida or South Carolina by Melvill (74, p. 167) is no doubt 

 erroneous. Sowerljy's figures of this species in the Conchologia Iconica are 

 binneyi Tryon. 



Pl^ANORBIS CRISTA L. 



Planorbis nautilcns, Walker, Naut., 1897, X, p. 117; Hanham, Naut., 1897, 



X, 130; Taylor, Naut., 1897, X, p. 139. 

 Planorbis costatus DeTarr and Beecher, Leaflet, Albany, 1878; Baker, 



Naut., 1906, XIX, p. 120. 

 Range : Maine, west to Alberta and Illinois. 



Planorbis cui/i'ratus Orbigny. 



Planorbis cultratus Orbigny, liist. Cuba Moll., 1853, (Fr. ed.) I, p. 196, pi. 



14, figs. 5-8; Pilsbry, Naut., 1889, III, p. 63, pi. I, l\g. 1-3. 

 Type locality : Cuba ? 



Listed from Miami, Fla., by Rhoads (113, p. 48) and by Pilsbry from 

 Hidalgo, Tex. (88, p. 63) and by Pilsbry and Ferriss from Devil's River. 

 Val Verde Co., Tex. (106, p. 165). 



Planorbis declivis Sowerby. 



Planorbis declivis Sowerby, Con. Icon., Planorbis, 1876, Sp. 28, pi. 4, 



fig- 29. 

 Type locality : ? 



Von Martens (73, p. 397) thinks that this is probably a form of trivol- 

 vis. The name is pre-occupied by Tate (1870), for a species from Nica- 

 ragua. 



Planorbis dlflectus Say. 



Planorbis dcflcxns Sowcrbx, Con. Icon.. Planorbis, 1876, Sp. 88. pi. XI, fig. 

 88. 

 Dall (32, p. 94) considers this doubtfully distinct from hirsiitus and 

 apparently identical with the European form known as draparnaudi or 

 draparnaldi Shepp. 



Planorbis dilatatus Gould. 



Includes bnchancnsis Lea according to Tryon (132, p. 209) ; vircns and 

 clei'afus according to Vanatta (136. p. 55); and lens, alabauicnsis and 

 buchanensis according to Dall (32, p. 92). 



