FAMILY TURBINID.E LACUNA. Ill 



ClNGULA LiEVIS. 



PLATE VI. FIG. 118. 



(STATE COLLECTION.) 



Description. Shell small, moderately solid, elevated. Whorls five, very convex, and 

 separated by a deep suture ; the two upper whorls rather rapidly diminishing in size. Sur- 

 face smooth, but (under the lens) exhibits faint traces of incremental lines ; the two lower 

 whorls more than half the total length. Body-whorl large ; aperture small, nearly regularly 

 oval, slightly angulated above ; pillar-lip arcuated, elevated, and partially everted over the 

 distinct and rather large umbilicus. 



Color. Opake white in the adult ; transparent corneous in the young, with occasionally the 

 upper whorls deep black. 



Length, - 2; of aperture, 0'08. 



I received numerous specimens of this shell from the Rev. Mr. Linsley of Stratford 

 (Conn.), who obtained them from the crop of a wild duck. I then referred it to Odostomia, 

 and gave a specific name which recalled the form of a Limnea. I was subsequently fur- 

 nished with specimens by Dr. Charles Stillman, who obtained them at Bushwick inlet, near 

 the city, where they had been washed upon the shore after a storm. The above dimensions 

 are given from one of the largest size. In its general form it resembles C. aculeus, with 

 which indeed it may, perhaps, be identified. It differs from C. minuta by its constantly 

 greater size, the smallness and more inferior position of the aperture, the wide umbilicus, 

 and deeper suture. 



GENUS LACUNA. Turton. 



Shell globose or conical, thin ; covered with a smooth epidermis. Spire short, consisting of 

 a few rapidly enlarging whorls. Aperture semilunar, rounded at the extremities. Colu- 

 mella oblique, reflected over part of the umbilicus, which forms a lengthened groove. 



Lacuna vincta. 



PLATE VI. FIG. 119. a. B. c. 



(STATE COLLECTION.) 



Turbo vinclus. Montagu, Test. Brit. 307, pi. 20, fig. 3. 



Lacuna pertusa. Conrad, Jour. Acad. Nat. Sciences, Vol. 6, p. 266, pi. 11, fig. 19. 

 Lacuna vincta. Gould, Invertebrata of Mass. p. 262, fig. 178. 



Description. Shell small, thin, ovate-conic : spire pointed ; whorls five, very convex, with 

 faint incremental lines ; suture deep ; aperture nearly circular ; lip sharp and simple ; pillar- 



