CONCHOLOGIA CESTRICA. 65 



Whether (as has been alleged) L. elodes, Say, and L. 

 catascopium, Say, are mutually convertible species, we 

 are, at present, unable to decide. 



L. reflexa, SAY. 



Ly mneus reflexus, Say, Jour. Acad. Phila. F.S., II., 1821. 



Shell, much elongated, pale brownish; ^JT]' 

 whorls 6, oblique; spire one and a half the Pig, 124, 

 length of the aperture, slightly reflected from 

 the middle ; two or three terminal whorls vit- 

 reous ; aperture narrow ; lip with a pale mar- 

 gin, and colored sub-margin. H. 30, W. 10, 

 mill. 



Station, in lakes and ponds. New Garden, 

 Chester County. 



L. desidiosa, SAY. 



Lymneus desidiosus, Say, Jour. Acad. Phila. F. S., II., 

 1821. 



Shell, oblong, sub-conic, thin, brownish, 

 or light ochraceous ; whorls 5, convex; 

 suture deep ; lines of accretion coarse, with 

 a tendency to form facets, on the body 

 whorl ; spire rapidly attenuated to an acute 

 point, as long as the aperture; columellar 

 fold slight; umbilicus small. H. 8, W. 4^, mill. 



Station, ponds and streams. Chester County; common. 



L. humilis, SAY. 



Lymneus humilis, Say, Jour. Acad. Phila. F. S., II., 1 822. 



Shell, ovate-conic, thin, translucent ; whorls *< 



I AV C* R 1 



5-6; aperture equal to the spire, with a cal- F .' 126 



careous deposit on the pillar lip ; umbilicus A. 



distinct; color yellowish, or reddish-white. feA 



H. 6, W. 3, mill. ^ 



Station, sluggish rivulets. Chester County ; common. 

 6* E 



