Shell white, medium in size, generally not exceeding 18 mm. in length, thin and rather low, the height varying from 43% to 50% of the length. Base ovate. Anterior slope long and strongly convex, posterior slope short and strongly concave around the apical whorls, then slightly concave to the margin. Apical whorls very small, one and one half, inclined backwards and downwards to occupy a position halfway between the summit and the base and rather near the posterior end of the shell. They are also conspicuously turned to the right. Anal fasciole long, rather deep, bordered by sharp edges and with widely-spaced, raised, semilunar lamellae which are much less numerous than the concentric cords that cross the shell. Fissure at the middle of the anterior slope, rounded behind and narrowing in front to a point. Sculpture very compact, consisting of about 28 strong radiating ribs starting at the base of the apical whorls. Lower down a secondary rib appears between each two of the primary ribs; they are at first rather fine, increasing in diameter until they equal the size of the primary ribs at the margin. Finally a thread is intercalated between the primary and the secondary ribs. Two ribs, a little stronger than the rest, border the fine groove that extends from the lower end of the fissure to the anterior margin. Numerous closely-set concentric cords cross the shell forming elongated and rather strong nodules where they intersect the ribs. Since ribs and cords are closely-set the shell has a granular appearance. Margin finely denticulated. Interior of shell nacreous-white, extending into the apical whorls. The radiating sculpture shows through as translucent fine grooves which increase in depth as they approach the margin. The anal fasciole is marked by a thick elongated callus. Internal septum convex, narrow and short, its length being less than half that of the fissure. A ridge is developed along each side of the fissure, starting from the outer edges of the septum and continuing to the margin. These are separated beyond the fissure by a fine groove.

This species is very close to P. (Cranopsis) asturiana, but differs from it by having the apical whorls smaller, placed halfway between the summit and the base and near the posterior end of the shell, while in asturiana they lie immediately below the summit and behind the center of the shell. In addition, antillana is thinner and smaller, probably not exceeding 14 mm. in length, and has a more compact sculpture, which gives a granular appearance to the surface of the shell. Dall (i.e.) made reference to the differences shown by some specimens of asturiana from the Antilles, but considered them to be mere variations, stating that these specimens intergraded with the typical in a larger series. We have examined Doll's material and find that they do not intergrade, but show the differences given above.

Along the West Indies.