Cerion hyperlissum Pilsbry & Vanatta. Pl. XI, fig. 10.
Shell moderately strong, much elongated, cylindrical, the latter four whorls of about equal diameter, those earlier gradually tapering, forming an obtuse cone with slightly convex outlines. Pinkish brown (with more or less white maculation), the riblets white. Whorls l1½, weakly convex, those of the cone smooth, the rest sculptured with rather fine riblets narrower than the intervals, about 36 in number on each of the several later whorls. Umbilicus a short rimation, compressed.
Aperture ovate, decidedly higher than wide, the throat flesh-tinted. Peristome white, well reflexed and revolute, thickened; parietal callus light, its edge hardly thickened; parietal fold median, very long, one-fourth to one-third of a whorl in length.
Alt. 32½, diam. 10; alt. of aperture 12 mm.
Alt. 29½, diam. 10; alt. of aperture 11 mm.
Cuba.
This species has the unusually long parietal tooth of the Cayman Island Cerions. For the rest, it does not differ remarkably from such Cuban forms as C. maritimum. The whorls of the cone are ribless.
A form also referable to this species is much striped and maculated with fleshy-brown and white, the riblets being finer. (Pilsbry & Vanatta, 1896:330)