LIMNEUS EMARGINATUS. 



DESCKIPTION. 



Shell subovate, somewhat thin, transhicent, ventricose : 

 volutions nearly four, convex : suture deeply impressed : 

 j^y /re somewhat prominent, eroded : aperture iwo thirds of 

 the length of the shell : columella with the fold very deep. 



SYJsONYM. 



L. EMARGINATUS, S. Joum. Jiccul. Nut. Sc. vol. 2, p. 170. 



OBSEliVATIONS. 



This is a somewhat larger, and considerably more ven- 

 tricose species than L. catascopium, S., and the undula- 

 tion of the columella is much more profound. In gene- 

 ral obesity it has a resemblance to L. inflatus, Brong. It 

 was first sent to me by Mr. Aaron Stone from the lakes 

 of Maine. Dr. Bigsby presented me with a sj)ecimen 

 which he obtained in Upper Canada, and 1 have recently 

 received several from Mr. Titian Peale, also found in 

 Maine, one of which is double the size of the figure repre- 

 sented in our plate. 



REFERENCE TO THE PLATE. 



Fig. 1, Back and front views; natural size. 

 PI. 55. 



