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Show 114 MR. G. NEVILL ON THE [Feb. 1 7, surface, of a closely allied, even more characteristic form whorls more convex, the last one perfectly rounded, with its base quite convex; aperture as in var. grimaldiensis; it appears to have been less smooth. Alt. 21, diam. 27| millim. Measurements below from Pfeiffer, Mon. i. p. 273:- Alt. 21, diam. maj. 35, min. 27 millim. HELIX (CAMPYL^EA) MAURELIANA, Bourg. MS. (Note compl. sur des Moll., Mammif. &c, Cav. pres de Vence, 1868, p. 5, name only). I am indebted to Mons. Bourguignat for the following Latin diaguosis: - " T. profunde angusteque umbilicata; depressa, subtranslucida, argute striatula, nunc surdo-albida, olim corneo-viridescenti zonulis tribus intensioribus (quorum duee superiores, angustce; tertior inferior, lata, ad regionem umbilicalem evanescens) spira depressa, parum convexa; apice obtusissimo, sat valido, argutissime granulata ; anfractibus 6 regulariter crescentibus, supra convexis ac sutura profunda separatis ultimo validiore, compresso-rotundato, prope aperturam coarctato, ac ad insertionem labri vix descendente; apertura parum obliqua, lunata, externe rotundata, infra rectiuscula arcuata; peristomate acuto, patulo ac refiexo ; labro supero refiexo; labro columellari brevissimo, circa regionem dilatato. "Alt. 11-12, diam. max. 21-23 millim. " Caverne Mars, pres de Vence, Alpes-Marit." (Cl. J. R. Bourguignat, in litti) Var. ROBUSTA, G. Nevill. Fairly abundant in deposits A, B, D, and E, but very difficult to obtain any thing like perfect specimens. The Menton specimens are rather larger and of a more robust variety than the typical Vence form. In deposit A a subvar. minor was not uncommon, with more compressed whorls, less produced (almost rounded) aperture, and less open umbilicus, the columellar margin a good deal less oblique. A very characteristic feature in Menton specimens of H. maureliana are the often very conspicuous " varices," especially noticeable in young specimens, as in Nanina, section Bensonia (N. monticola, &c); this, of course, is due to a thickening within the peristome, at different periods of growth, only partially absorbed when the animal recommences the growth of its shell. Mons. Bourguignat writes me that its nearest ally is H. zonata, Studer, of which he is inclined to consider it as " une forme atavique." It differs materially from all the varieties I know of H. planospira. Var. robusta, from deposit D (figured). Alt. 13^-, diam. 25| millim. Subvar. appressa, from deposit B. Alt. 12£, diam. 23| millim. |