Shell regularly elongate-conic, dull brown; nuclear whorls having their axis at nearly right angles to and about one half immersed in the first postnuclear whorl, above which the edge appears; postnuclear whorls 12, flat sided, high between the channeled sutures; periphery of the last whorl marked by a distinct sulcus; entire surface marked by
lines of growth and very fine spiral striations; base inflated, strongly rounded, with a narrow, open umbilicus bounded by a strong, axially striated cord; aperture oval, with a slight anterior canal; outer lip thin, showing 3 faint white spiral lines deep within the aperture; columella slender, with the continuation of the basal cord forming a strong lamellar fold at its insertion, below which are 2 much weaker and more oblique folds. The type measures: length, 8.8 mm; diameter, 2.8 mm.
Holotype: No. 739 (Calif. Acad. Sci. Paleo. Type Coll.), from Loc. 27,228 (C.A.S.), dredged in from 3 to 9 fms. off Taboga Island, Panama. L. G. Hertlein collector. Eight additional specimens were dredged at the same locality.
In general shape this species resembles Pyramidella conica C. B. Adams,25 but the presence of the open umbilicus is a marked difference. The only other umbilicated species described from the west coast, Pyramidella bairdi Dall & Bartsch from the Gulf of California, is an entirely differently shaped shell.