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Show 192 MR. E. A. SMITH ON MOLLUSCA FROM JAPAN. [Feb. 18, far apart, and are not found in the excavation at the upper part the volutions : aperture small, occupying rather more than a third of the entire length ; sinus deep, inferior sinuation very shallow ; canal very wide, not recurved ; columella covered with a pale brownish callosity, tuberculated at the upper extremity. Length 18 millims., diam. 6. Hab. Station 15. This species is closely affined to P. obliquata, Reeve. It differs in being more slender, has a narrower concave portion at the top of the whorls, and consequently longer rounded sides; the costa? are more numerous and less produced inferiorly on the last volution; and the surface, with the exception of the upper or depressed part of the whorls, is ornamented with fine subdistant lirula?, which in obliquata are altogether wanting; the basal canal, too, is broader, and the labrum has not the large swollen varix behind it which is characteristic of Reeve's species. 23. DRILLIA CANDENS. (Plate XIX. fig. 17.) Shell shortly subfusiform, entirely white, shining, subpellucid: whorls 8, two nuclear ones large, globose, smooth, the rest rather bulging towards the lower part, and a little constricted above, obliquely ribbed and striated by the lines of growth ; costae stouter on the upper whorls than on the last, on which they are obsolete at the middle; they are very oblique and flexuous ; the lower part of the body-whorl is sculptured with fine oblique grooves, which by degrees are less distinct on the upper portion; sinus very wide and deep, inferior sinus slight; columella but little oblique, sinuous, covered with a white shining enamel, with a small tubercle at the upper extremity ; canal broad, very short, and not recurved. Length 12 millims., diam. 4|. Hab. Stations 1 and 15. This is a very pretty species, of a diaphanous white tint, a little more opaque just beneath the suture. Besides the fine lines of growth, other stria? in a transverse direction, and equally fine, can be discovered in parts under a powerful lens. For such a small shell the sinus is remarkably large and deep; the apical whorls, too, are proportionally large. 24. DRILLIA RARICOSTATA. (Plate XIX. fig. 18.) Shell elongate, shining, horny brown: whorls 8, two apical transversely keeled and angled round the middle ; the rest concavely excavated above, convex below, coarsely obliquely plicated, and somewhat margined beneath the suture; plica? abruptly terminating at the concavity, eight on a whorl, very oblique, gradually shorter on ascending the spire, so that the upper rather acute ends fall about the middle of the whorls ; costa? on last whorl obsolete at the base, which is obliquely grooved : aperture very small, about one third as long as the whole shell; sinus deep, inferior sinuation shallow ; labrum thin, curved and prominent, with a swollen varix some distance behind the margin ; columella scarcely oblique, but slightly sinuous, |