Shell acuminately fusiform, shining, and very smooth ; whorls 12, of which the two nuclear are transparent, white, and slightly bulbous; the remainder moderately suturally impressed, with a plicate and conspicuous revolving keel just below the suture, a plain space just below this, and then, joining on to the suture below, another carina raised and ornamented with a spiral row of small shining nodules. The body-whorl is almost straight, quite smooth, shining, and milky white until the close rows of striae commence round the base. Canal prolonged and recurved, outer lip hardly incrassate, sinus wide and well-formed, columellar margin straight, mouth oblong.
Long. 28, lat. 9 mm.
Hab.—Goree, West Africa ; collection Denans.
This extremely select species was examined by the late Mr. G. B. Sowerby, who wrote that at first he considered it might be an albino variety of P. lineata Lam., but that it was well distinguished from that species by the " plicate angle It certainly seems abundantly distinct from any other known Perrona.