HELIX. 97 



perhaps, be referred to the following species. It was found 

 at Fort Bridger. 



Say's type is still preserved in the Academy at Phila- 

 delphia. 



The species occurs in the Postpleiocene. It is doubtful 

 whether it will ever be found in New York as DeKay an- 

 ticipates. 



HELIX COOPERI. 



Plate LXXVII. Figure 11. 



Testa umbilicata ; elevato-globosa : solida ; striis obliquis incrementi et 

 lineis spiralibus leviter intercidentibus notata ; alba, ad peripheriam fas- 

 cia unica, angustt, rufa, cincta, aut fasciis et lineis rufis, volventibus, 

 varie dispostis, ornata ; sutura impressa ; spira elevata ; anfr. 5 convexi, 

 ultimus rotundatus, ad aperturam valde descendens ; umbilicus mediocris, 

 pervius, 1-5 diam. maj. testae jequans ; apertura perobliqua, circularis ; 

 perist. simplex, incrassatum, ad umbilicum reflexiusculum, marginibus 

 valde approximatis, calio albo, crasso, conjunctis. 



SYNONYMS AND KEFEKENCES. 



Helix Cooperi W. G. Binney, Proc. Acad. Nat. Sc. Phila. 1858, p. 118 ; Notes, 

 p. 16. 



DESCRIPTION. 



Animal not observed. 



Shell umbilicated ; elevated, globose ; solid, with ob- 

 lique incremental striae intersected with delicate spiral 

 lines ; color white, variously marked with a single narrow 

 band, or broader longitudinal and spiral patches of reddish- 

 brown ; suture impressed ; spire elevated ; whorls five, 

 convex, the last rounded, very decidedly deflected at the 

 aperture ; umbilicus moderate, pervious, l-5th the greater 

 diameter of the shell; aperture very oblique, circular; 

 perist. simple, thickened, reflected at the umbilicus, with 

 its extremities very nearly approached, and joined by a 

 heavy white callus. 



Greater diameter, 15 ; lesser, 13 ; height, 9 millimetres. 



Geographical Distribution. Found by Dr. F. V. Hayden 

 13 



