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Show 116 MR. G. NEVILL ON THE [Feb. I 7, elevated spire; without exception, as far as 1 could see, imperforate, with large and produced aperture, deflected last whorl, and fairly vivid markings. Specimen from Sainte-Agnes-alt. 17}, diam. 25} millim. From the " Berceau"-alt. 15, diam. 24} millim.; and another-alt. 17}, diam. 24} millim. Subvar. COLORATA. I did not find this species at all in the " Couche Marneuse " of Cape Mortela (zone of //. paretiana), though I have but little doubt it occurs. I found it, however, associated with II. paretiana near Monaco, and at another spot in a cutting of the railway, the single specimen from the latter locality being a most remarkable small form, the chestnut maculations being most unusually broad and close together, so much so as to amount to bands; there are three of these slightly interrupted bands on each of the last few whorls ; the aperture also is less produced, the apex more prominent, and the whorls more compressed. Alt. 14, diam. 19} millim. Subvar. PRIMITIVA. Closely allied to the living form still to be found near the summits of the neighbouring Alps ; imperforate, of thin texture ; spire more or less raised, not nearly so depressed as in the next variety, with prominent apex ; whorls moderately convex, the last one abruptly deflected, convex at base ; both aperture and last whorl a trifle smaller in proportion than in the living form; the columella very similar, only moderately oblique, forming a slight angle at its termination, slightly twisted, imparting to it a subtuherculose appearance. This was one of the commonest (and best-preserved of the large species) in deposits A, B, C, E. Curiously enough, the species did not occur at all in deposit D; probably this locality was not sufficiently sunny. I have great doubts whether I have done right in separating this form, even only as a subvariety, from its close ally, living on the neighbouring mountain-tops; probably both had better be classed together as subvar. primitiva, characterized by the thin texture &c. Alt. 16, diam. 2KZ millim.; another-alt. 17, diam. 24} millim. Types of preceding subvars., Indian Museum, Calcutta ; the latter also in coll. M M . Bourguinat, Coombe Williams, and Joly. Var. SPELUNCARUM, nov. As to the necessity of separating this form there can be no two opinions ; it is an exceedingly well and constantly characterized depressed variety, presenting a most distinct " facies." It was abundant in deposit F, and, I have reason to believe, was the principal shell found inside the cave by M . Riviere, mixed with mammal-bones & c , judging from specimens in the museum, and from an examination of the earth dug out from these caves. Markedly and in |