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Show 128 MR. G. NEVILL O N T H E [Feb. 17, scentes, ultimo longiore, basi vix compresso ; apertura amplior, inferne minus contracta, margine columellari rectiore. Long. 5, diam. If millim. Type, Indian Museum, Calcutta; also in coll. M M . Bourguignat, Coombe Williams, P. Joly, P. Fagot, and Colonel Godwin-Austen. This was exceedingly abundant in deposits A, B, C; I found a single specimen in deposit F, of a short thickset variety (var. tumida), probably enough a distinct species. Typical Pupa bipli-calu, Mich., and P. ressmanni, Villa, are the nearest forms I know to P. bourguignatiana ; from both the present species can be told at once by the above-described characters of the aperture. A specimen from Tuscany, which I obtained from Madame Vimont at Paris, labelled P. biplicata, is a totally distinct species from the Menton one ; it is the P. toscanice oi Bourg. Var. PLAGIOSTOMA, nov. (Plate XIII. fig. 6.) (An potius Pupa plagiostoma, n. sp. ?) This is a well-marked and very distinct form, distinguishable at a glance by the characters of the aperture, which appear to be constant ; it was by no means rare in deposits B and C. Spire slightly convex, less gradually tapering (or turreted); whorls 8£, the first 3^, increasing rapidly, the others of almost equal breadth, the last one longer in proportion, more compressed at its base, so much so that it has a subcarinate appearance round the umbilicus ; striation a little more distinct and more oblique; aperture quite differently shaped, not triangular, but more compressed, narrowly oblong, as broad at its base as above; both columellar and parietal folds more twisted, the former less straightly transverse ; the two palatal ones, seen through from the back, appear more callous and to run into one another, in the type form they appear to run more or less parallel; the peristome even more callously thickened, with its margins joined by a more developed callosity ; the columellar margin has a very slight bend at its commencement, otherwise it is quite straightly oblique, without the characteristic deflection of P. bourguignatiana ; the callous tubercular tooth on the outer margin equally prominently and robustly developed ; this tooth appears to be peculiar in the group to the Menton species, in which it exists in every specimen and in all the varieties, the other species merely possessing a slight thickening in its place, as far as I know. Long. 4\, diam. \\ millim. Subvar. ANGUSTA, nov. This is a by no means rare form, which has decided me on not specifically separating the preceding; it has a similar aperture, as also a coarser striation, but possesses 10 whorls, the first eight of which are even more cylindrical than in the type form, and more compressed, the last two being in proportion stouter and more convex, imparting to the spire a remarkable emaciated appearance. Types of the variety and subvariety are in the Indian Museum, Calcutta ; also in collections of M M . Bourguignat and Coombe Williams. |