spaced nearly straight growth-lines, crossed by fine, some-times very indistinct, spiral striæ. Colour white, occasionally tinged with yellowish or pink. Spire conic, about 1 ½ times the height of the aperture; outlines straight. Protoconch very small, heterostrophe, of 1 smooth whorl. Whorls 8 in quite adult examples, but the shells usually obtained have 6 whorls; they increase regularly, are flatly convex, and the last whorl is usually distinctly angled at the periphery, but some-times rounded. Suture impressed, submargined below. Outer lip sharp, slightly convex; basal lip acutely convex and expanded. Columella oblique, with a prominent oblique plait above, concave below; inner lip broadly reflected below, spreading as a very thin callus over the parietal wall. Base with a distinct umbilical fissure.

Diameter, 3.5 mm.; height, 7.5 mm. Specimen of 8 whorls.

Diameter, 3 mm.; height, 5 mm. Specimen of 6 whorls.

Type in the Dominion Museum, Wellington.

Hab.—Stewart Island, type; Lyttelton Harbour, in 2 fathoms. (H. S.); Akaroa Harbour, in 6 fathoms (H. S.); Blind Bay; Narrow neck Reef, Devonport (H. S.); near Channel Island, Hauraki Gulf, in 25 fathoms.

Fossil in the Pliocene.

Remarks.—The Australian O. angasi, Tryon (= O. lactea, Angas), is a much more slender, subulate species, which has the body-whorl rounded, never angled.