"Cerion crassiusculum Torre. Figs. 7, 8.

Shell rimate, cylindrical, rather solid, lusterless, light hrown or yellowish-brown throughout.   Latter three whorls of equal diameter, or wider above, those above tapering in a short cone with straight or slightly concave outlines; apex obtuse, rather mammillar.  Sculptured with rather close, regular, strong riblets, which are some­what oblique, varying from as wide to half as wide as the interstices, and about 28 in number on the antepenultimate whorl; becoming obsolete or partially so on the last whorl. Whorls nearly 10, but slightly convex, the last slightly ascending in front.

Aperture vertical, with a very small, short parietal tooth, and moderate axial fold; peristome blunt, expanded, subreflexed, the terminations distant, connected by a moderate parietal callus.

Alt. 20½ diam. 8½ length of aperture 7½ mm.

Alt. 20, diam. 9½, length of aperture 8 mm.

Cayo Juin, Baracoa, Cuba (Prof. de la Torre, F. E. Blanes).

There is a small form, alt. 13, diam. 6⅓, length of aperture 5 mm., having all the characters of the larger except that there are only 8 whorls.

The last whorl in this species is half the total length of the shell or a trifle more, and upon it the ribs are weak or wholly obsolete. Compared with C. incrassatum microdon, it differs in the concave instead of convex outlines of the terminal cone, and the color. It differs from C. tenuilabre in the coarser sculpture; and from both in the comparatively smooth last whorl."  (Pilbry & Vanatta, 1899:477-478)