19. Pleurotoma (Leucosyrinx) eremita, n. sp. Plate XXII, figs. 18, 19.
Shell small, fusiform, fragile, with shouldered whorls, the body-whorl but slightly shorter than the spire, and a rather short open canal. The sculpture consists of longitudinal and spiral threads and riblets, the former inclined slightly backward; they number about fifteen on the penultimate whorl and are obsolete above the angle, absent upon the greater part of the last whorl. The spirals consist of five minute threads on the slope above the angle; beneath the latter there are four much stronger riblets, forming gemmules at the intersections of the longitudinals; the last whorl with about twenty-three spirals, those upon the base and neck more widely spaced, but equally slender as those on the shoulder. Colour light-cream. Spire turriculate-conical, with a blunt apex. Protoconch slightly bulbose, with about two smooth whorls, nucleus globular. Whorls 5, angled at the periphery, straight above, slightly convex below; base convex, then contracted and ending in a short distally rounded beak. Suture deep. Aperture pyriform, broadly angled above, ending in a rather short almost straight canal, slightly turned to the left. Outer lip imperfect, convex above, contracted near the base; it is evident from the growth-lines that the sinus is broad, rounded, and moderately deep, extending almost from the suture to the keel. Inner lip forming a thin and narrow callosity on the almost straight columella, which is slightly twisted at the base. Altitude, 5·8 mm.; diameter, 2·42 mm.
Type in the Colonial Museum, Wellington.
Obs. Of this species there is but a single and not fully adult example, a dead shell, which appears to be allied to P. ischna, Watson, which was obtained in 700 fathoms north-east from New Zealand. Our species is smaller, less slender, with fewer whorls, and has much more numerous and stronger spiral riblets, especially round the periphery of the whorls. The situation of the sinus seems to be the same in both species.