Shell about 10 mm. in length, thin but strong, low conical, expanding toward the margin, its height being 45% of the length. Color a pure dull white. Base ovate, narrower in front. Anterior slope convex, posterior slope straight. Apical whorls one and one quarter, increasing very rapidly in diameter, with the surface puncticulate. They are on top of the shell but at the same time are turned somewhat backwards and downwards and placed a little behind the middle. Fissure short, tear-shaped, the upper end being rounded. From this end of the fissure a short anal fasciole runs to the base of the apical whorls, being provided with only five incremental lamellae. From the anterior end of the fissure a shallow ridge runs down the middle of the front slope. The surface is sculptured with 32 rather strong, radiating ribs between each two of which a finer one is intercalated. Concentric cords cross the shell forming elongated nodules where they intersect the ribs and give to the shell surface a cancellated appearance. Margin finely crenulated by the ends of the ribs. Interior of shell a nacreous-white with the outer ribs showing through in the form of very fine radiating grooves. Internal septum strongly arched and long, extending down beyond the fissure. Below the septum there is a low ridge on each side of a shallow and fine groove which extends toward the anterior margin of the shell. The ridges are extensions of the sides of the septum where it is attached to the shell. Length 10 mm; Width: 6,75 mm; Height: 4,5 mm. Holotype, in the United States National Museum, no. 44837, from South of Martha's Vineyard, Massachusetts,in 1537 fathoms.

This species seems to be related to P. noachina but the two can readily be differentiated: P. abyssicola is much less elevated and is expanded instead of being compressed; the primary radiating ribs are more numerous, only up to 20 in number in noachina while in abyssicola there may be 32. Finally, strong concentric cords are very conspicuous in abyssicola, but are absent in noachina.