132 Descriptions of New Species of SJiells. 



virente ; spirit parum elevata, apice obtusiuscula ; anfr. 4, celeriter accre- 

 scentibus, convexis ; sutura profunda ; umbilico inediocri, profundo ; 

 apertura subobliqua, circulari, perist. simplice, contiuuo, recto, marginibus 

 approximatis: operculo corneo, tenui, arctispiro, extus concaviusculo ; 

 anfr. 8k. 



Shell umbilicate, orbiculate, and somewhat conical, rather 

 thin, with oblique hardly perceptible stria3 of growth ; color 

 of a light greenish-yellow, verging towards olive ; spire not 

 much elevated, with the apex rather obtuse ; whorls 4, rapidly 

 increasing, convex, suture deep, umbilicus moderate, deep ; 

 aperture somewhat oblique, circular, its outline hardly broken 

 by the penult whorl ; peristome simple, continuous, straight, 

 its margins approximate : operculum horny, thin, a little con- 

 cave without, closely spiral, with 8-J whorls united by inconspi- 

 cuous sutures. 



Greater diam. 0.45 inch (11 millim.). Lesser diam. 0.40 inch 

 (10 millim.). Height 0.24 inch (6 millim.). 



Length of aperture 0.21 inch (5 millim.). 



Habitat. — Guadaloupe. 



Obs. — In size and form this species approaches O. asperulum 

 Sow., but differs entirely in its surface. In color and general 

 habit it is related to C. translucidum Sow., but is more depressed. 

 Its operculum is also quite different from that of either of the 

 above species, and would bring it within the proposed artificial 

 subgenus Ci/clophorus. Its natural affinities, however, would 

 bring it much nearer to species which have been placed in the 

 equally artificial subgenus Cychtus. Mr. Bland has kindly 

 afforded me the opportunity of describing this shell, which was 

 communicated to him by Henry Krebs, Esq., of St. Thomas, 

 W. I., who gives M. Duchaissaing as authority for the above 

 habitat. 



