Go to National Library of New Zealand Te Puna Mātauranga o Aotearoa
Volume 38, 1905
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14. Drillia optabilis, n. sp. Plate XXI, fig. 9

Shell small, narrow, turriculate, last whorl shorter than the spire, clathrate, aperture pyriform, canal short. Sculpture: On the spire-whorls three spiral equidistant cords, which are crossed by longitudinal also equidistant threads, forming small beads at the intersections, and squarish interstitial depressions; there are about twenty-one beads on a row; on approaching the base the spirals are getting narrower than the interspace, and the beading less prominent; upon the beak there are small irregular threads crossed obliquely by the plications of the old beaks. Colour greyish-white. Spire turriculate, not very conspicuously shouldered, longer than the last whorl. Protoconch: The outer shelly layer has scaled off and it is impossible to give a description; the nucleus is globular and obliquely tilted. Whorls 7, narrowly angled and excavated above, sides almost straight; base convex and narrowed to a short and anteriorly sinuated beak. Suture bimarginate, above by a minute threadlet, below by a broad and heavy cord which is obliquely irregularly plicated. Aperture pyriform, angled above, with a concave inner wall, ending in a short broad canal, which turns slightly to the left. Outer lip curved, imperfect; the lines of growth would indicate that the sinus is situate in the excavation below the sutural cord, that it is small and moderately deep. Inner lip spread as a thin layer narrowly over the body, broader over the columella, which is first straight and then slightly twisted to the left, ending in a sharp point. Altitude, 10·7 mm.; diameter, 3·93 mm.; angle of spire, about 22°.

Type in the Colonial Museum, Wellington.

Obs. A single specimen of this beautifully sculptured shell was collected.