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Show 1882.] MOLLUSCAN FAUNA OF MADAGASCAR. 379 still finer. C. sarcodes, Pfr., is still higher in the spire, with volutions, and more strongly lirate, especially on the lower surface of the last whorl. VITRINA MADAGASCARIENSIS, sp. nov. (Plate XXI. figs. 6, 7.) Shell ventricose, depressed, very thin, diaphanous; pale greenish yellow, with a brown line at the suture, and with the upper part of the outer lip of the same colour, brilliantly glossy. Spire small, a little elevated and obtuse at the apex. Whorls 3|, convex, deep, and margined above at the suture; the first 1| microscopically decussated in a beautiful manner by minute spiral striae and very fine lines of growth, the last two lacking the spiral striae. Body-whorl large, with distinct, here and there subplicate, lines of growth, on the lower surface exhibiting indications of interrupted concentric striae. Aperture subhorizontal, large. Columella arcuate, thin, wrinkled, as is also the base of the peristome. Greatest diam. 15| millim., smaller 12, height 9. Hab. Betsileo (Cowan). This I believe is the only species of Vitrina at present known from Madagascar; and it bears some resemblance to certain forms of the genus from South Africa. HELIX (NANINA ?) BALSTONI, Angas. H. balstoni, Angas, Proc. Zool. Soc. 1877, p. 528, pl. 54. f. 5. Hab. Interior of Madagascar (Angas) ; forest 36 miles east of Antananarivo (Johnson). The specimen presented to the British Museum by Mr. Johnson is narrowly perforated, in which respect alone it differs from the description of this species given by Angas. Two other shells in the Museum are also narrowly perforate; and even the above-quoted figure looks as if the example delineated were likewise umbilicate ; so that it is possible the species was described as " imperforate " accidentally. HELIX (NANINA?) CLEAMESI, sp. nov. (Plate XXI. figs. 8, 9.) Shell very thin, semitransparent, vinous horn-colour, narrowly perforate, suborbiculately conical, keeled at the periphery, marked with curved lines of growth crossed and rendered minutely granular on the spire by fine concentric striae, more finely concentrically striated on the under surface, more glossy and not granulated. Spire with slightly convex outlines, shortly conical, ending in an obtuse tip. Whorls 6, a little convex, regularly increasing, a little depressed near the lower submarginal suture, or, in other words, just above their periphery. Last volution keeled above the middle, the carina being less marked near the outer lip. Base convex. Aperture somewhat oblique, lunate. Outer lip obliquely arcuate above the feeble carination, straightish or even a little sinuated below it in a very slanting or receding direction. Columella narrowly expanded and reflexed over the perforation, forming below, with the basal edge, a regular wide curve. |