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Show 206 MR. E. A. SMITH ON MOLLUSCA FROM JAPAN. [Feb. 18, spiral ridges, subequidistantly placed, of a rich reddish-brown colour. The operculum is typically fusoid, having a terminal nucleus, and differing in this respect from that of S. cassidaricefomm, thus showing how variable and unreliable the operculum is as a divisional character. 56. EUTHRIA FERREA, Reeve. (Plate XX. figs. 39, 39a.) Buccinum ferreum, Reeve, Conch. Icon. iii. 1847, p. 102. Fusus viridulus, Dunker, Moll. Japon. 1861, p. 3, pi. 1. f. 16 ; Lischke, Jap. Meer.-Conch. i. pi. 5. f. 5, 6 ; Smith, Ann. & Mag. Nat. Hist. 1875. Hab. Stations 8* and 28. " Tsu-Sima, O-Sima, and Nagasaki (A. Ad.) ; Decima and Nagasaki (Lischke). The type of this species is in a worn condition, and entirely destitute of the olivaceous epidermis exhibited by fresh specimens. However, there is not a shadow of doubt that it is identical with the shell described by Dunker as Fusus viridulus. It is a species subject to considerable variation in form, some examples being considerably more robust than others. Its operculum is typically fusoid, with an apical nucleus. 57. TRITONIDEA SUBRUBIGINOSA. (Plate XX. fig. 40.) Shell ovate, dark brown, with a luteous band around the middle of the last whorl, which is also partly seen upon the upper whorls just above the suture ; tip of the body-whorl luteous. Volutions 6|, the one and a half at the apex smooth; the rest very convex, obliquely plicated and spirally ridged ; plicae or costae large, swollen, broader than the interstices, ten in number on the penultimate whorl; transvere lirae four or five on a whorl, with finer intermediate ones, a trifle thickened upon the plica? ; the latter become obsolete upon the last whorl about the periphery. It is encircled throughout by spiral ridges, some of which at the basal extremity and between the strong ones above are very fine. Aperture occupying rather less than half the entire length, livid blue within ; labrum thickened exteriorly with a large tumid varix, thin and crenulated at the margin, armed within with about eight lira?, which are thickest at the end towards the lip ; columella covered with a thin callus, arcuate above, with a somewhat dentiform prominence at the middle, and one or two tubercles close to it, and another small elongate one above close to the termination of the outer lip ; canal oblique. Length 17 millims., diam. 7. Hab. Station 8*. This interesting little shell might, at first glance, be mistaken for a diminutive form of Buccinum rubiginosum, Reeve. It is, however, distinguished by fewer whorls, whereof the nuclear ones are actually larger than those of T. rubiginosa, and also by difference of coloration and the shorter aperture. The operculum is fusoid, with the nucleus terminal. |