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Show 1879.] MR. E. A. SMITH ON MOLLUSCA FROM JAPAN. 209 verse bands of the same colour spotted with white, one above and other below the suture. The body-whorl has a third similar band near the middle, and is obliquely finely grooved at the base. The banding upon the specimen from station 30 is less definite, and the form of the shell, too, is rather more slender. Length 12 millims., diam. 5. 65. COLUMBELLA (ZAFRA) SUBVITREA. (Plate XX. fig. 43.) Shell fusiformly ovate, subpellucid, white, with a thin indistinct brown line interrupted by the costae around the lower part of the whorls, and a transparent pellucid zone at the top, with a second band or series of short flames just below the middle of the last whorl, which is stained with brown at the extremity. Whorls 7, the first two convex, smooth, the following two or two and a half almost flat and likewise smooth, the rest strongly costate ; costae about eleven on a whorl, rounded, a little oblique, and more or less arcuate, narrowed and subobsolete at the upper extremity, disappearing a little below the middle of the body-whorl, the lower extremity or cauda of which is transversely and a little obliquely sculptured with five or six stria?, whereof the two or three uppermost are wider apart than the rest. Aperture narrow, occupying rather less than half the shell's entire length ; labrum thin, faintly and broadly emarginate, or sinuated just beneath the suture, smooth within ; columella a trifle oblique, tinged with brown, a little convex or swollen at the middle, covered with a thin callosity with a defined margin, which unites at the upper extremity with the termination of the outer lip; basal canal short, rather deep, and in a slight measure recurving. Length 4 millims., width 1|. Hab. Station 25. The genus Zafra is described by A. Adams in the 'Annals and Magazine of Natural History,' 1860, vol. vi. p. 331. He considers that it belongs to the Turrida? or Pleurotomidae. In his description he does not state whether the labrum bears internal lira? or denticles. I have examined a specimen of the typical species, and I do not discover their presence. The absence of these denticles appears to be the only character which distinguishes this group from the genus Seminella of Pease ('American Journal of Conchology,' 1867, vol. iii. pp. 233 & 234). In size and style of sculpture the species of the latter genus answers to the description of Zafra; and I am inclined notwithstanding that their lips are toothed within, to include them in that genus. It is possible that Z. mitriformis and Z. subvitrea in the very adult state at times may exhibit denticles. The latter species differs from the former in being narrow, differently coloured, and having the costa? obsolete on all except the last two and a half whorls. Anachis zonata, Gould (J = Zafra mitriformis), and Anachis virginea of the same author, also should be classed with Zafra. P R O C ZOOL. Soc-1879, No. XIV. 14 |