52 LIMNEA CATASCOPIUM. 



convex: suture very deeply impressed: apex 

 acute: body whorl a little flattened in the mid- 

 dle: aperture not dilated, columella with the 

 sinus of the fold very obvious." — Say. 

 Color .... bleached and chalky. 



OBSERVATIONS. 



This species is allied to L. humilis, but is 

 much thicker in texture, and has a better de- 

 veloped shoulder to the whirls. All the speci- 

 mens known, occur in a superficial deposit on 

 the margins of a pond or small lake in western 

 New Jersey, and I believe the species to be 

 extinct, with, perhaps, one or two others from 

 the same locality, which will bring this deposit 

 within the Tertiary period of geologists. 



LIMNEA CATASCOPIUM? 



Plate 14. 



OBSERVATIONS. 



Since the article on this species was publish- 

 ed, Dr. Mighels of Portland, Maine, has sent 



