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Show 214 MR. E. A. SMITH ON MOLLUSCA FROM JAPAN. [Feb. 18, (Dr. Livesay), and Louisiade archipelago (Macgillivray, Voyage of * Rattlesnake'). 80. MITRA (COSTELLARIA) SUBTRUNCATA, Sowerby. Mitra subtruncata, Sowerby, Thesaurus Con. iv. pi. 360. f. 405, sp. 468. Hab. Ooshima harbour, 8 fathoms, on a bottom of sandy mud and broken shells. Mr. Sowerby remarks that in sculpture this species resembles M. obeliscus. Judging from his figure and the specimens which I believe to belong to this form, this statement requires some qualification. To a certain extent there is some similarity; but the costellae in M. obeliscus are finer and more numerous, and the spiral sulci between them much deeper than in M. subtruncata. The ribs, too, in the former are subgranulous at the points where the spiral lirae between the sulci come into contact with them, whilst in the latter they are smooth and regular. The columella has five plaits, M. obeliscus only four. 81. MITRA (COSTELLARIA) FUSCO-APICATA. (Plate XX. fig. 49.) Mitra (Costellaria) suluensis, Smith (non Ad. and Rve.), Annals and Mag. Nat. Hist. 1875, xv. p. 425. Shell fusiform, whitish, stained with brown at the apex, obscurely banded with bluish ash a little below the top of the whorls, and spotted irregularly with brown in the same part, generally between the costae ; lower half of the last whorl cinereous brown. Whorls 10, one to two apical ones smooth, globose, the rest almost flat at the sides, scarcely turreted, longitudinally ribbed and spirally sulcated between the costa? ; the latter are about 17 in number on the penultimate whorl, a little arcuate and oblique, about half as broad as the interspaces between them ; spiral sulci interrupted by the costa?, five on the upper whorls, moderately deep, subequidistant: the ribs on the body-whorl alternate at the base, and at this part are cut across by the oblique transverse grooves, producing nodules upon them ; one of the ridges between the sulci, which is in a line or continuous with the uppermost fold on the columella, is conspicuous, being a little thicker than the rest. Aperture generally internally Urate, small, narrow, with a white band within a little above the middle, and two interrupted brown zones, one above and the other below the white one ; columella with a callus near the extremity of the labrum, with four folds, the two uppermost grooved so as to appear duplex; canal recurved. Length 24 millims., diam. 7 ; aperture 9 long, 2 wide. Hab. Station 19. Ooshima harbour (Annals 1875). This species is closely allied to M. suluensis, Ad. and Rve., with which I formerlly confounded it; it differs in having a non-turreted spire, finer spiral sculpture, a shorter aperture, and the colour, too, a little different. The bluish-ash zone at the upper part of the whorls in some specimens is almost entirely wanting, so that the |