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Show 1880.] LAND-SHELLS O F M E N T O N . 137 Mons. J. Rene Bourguignat, Coombe Williams, P. Joly, P. Fagot, and Colonel Godwin-Austen. Var. EMACIATA, nov. (Plate XIV. fig. 5.) This is a very difficult dwarf form, apparently varying in every specimen, and of which it seems to me impossible to grasp any tboroughly constant character. Taking an extreme specimen, it is distinguished by its smaller size, by the more regularly turreted spire being quite upright, 6 whorls, of almost equal size, slightly more convex, especially the last, which is also proportionally very short; aperture smaller, a trifle more vertical, and scarcely everted; callosity joining margins well developed ; peristome does not present the duplex appearance of the preceding, except at the columella. Rare, in deposit B only. Long. 3\, diam. (vix) 1} millim. Type var., Indian Museum, Calcutta; also in coll. Marquis de Folin and Mons. J. Rene Bourguignat. Var. PACHYSTOMA, nov. (Plate XIV. fig. 6.) (An potius A. pachystoma, sp. nov. ?) This, unlike the preceding, is an exceeding well marked and distinct form, unmistakable at a glance. I think it extremely probable Mons. Bourguignat is correct in regarding it as a distinct species. It can be known from the typical form by its much less distinct suture, by the shorter, less elegantly and regularly turreted spire, composed of only 6 more rapidly increasing whorls, the apical two compressed, the others scarcely convex, almost cylindrical, especially the last, which is proportionally much longer, the antepenultimate one much broader than the others (not the case in type form) ; the apical portion of the spire considerably more diverted from the axis of the shell, with the aperture very much everted, imparting a still stronger resemblance to certain species of Eulima; the thick white peristome is surrounded by a still more callous rib, especially noticeable at its termination, about the middle of the columella, which is slightly oblique; the duplex character of this outer lip is still more distinctly and clearly marked. This form was by no means uncommon, though much less abundant than typical A.foliniana, with which it was associated. Long. 5, diam. ly9^ millim. Type var., Indian Museum, Calcutta ; also in coll. Marquis de Folin and Mons. J. Rene Bourguignat. RENEA, genus nov. Hoc genus delectans ad amicum meum clarissimum J. Rene Bourguignat dedicavi; ad familiam Aciculidse, Gray, Ac-mseidse, auct.) pertinet. Testa imperforata, perelongata, cylin-drica, anfractibus numerosis, compressis ac costulatis, labro externo prope angulum superiorem (more Pleurotomorum) scis-sura notabili munito; margine peristomal obtuso, intus in-crassato, extus costa callosa nulla, sicut semper in genere |