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Show 1880.] LAND-SHELLS O F M E N T O N . 131 are moderately convex, short, regular, increase rapidly in breadth, the upper one closely costulated, the ribs scarcely oblique ; the lower one has these ribs more distant, less crowded and more acutely raised ; the next two, of about equal height and breadth, also increase rapidly in breadth, are very convex, the ribs become still a little more acute, more oblique and less crowded ; the antepenultimate has similar ribbing, is much the same in size, only a trifle more tumidly convex, it has the peculiar character that whilst on the side of the aperture it only just equals the preceding one in width, on the other side it markedly surpasses it: the last becomes abruptly much narrower above, about equal in width to the fourth whorl; on its centre it is girt with an impressed line, dividing it into two nearly equal portions, the lower of which becomes abruptly narrower and more compressed, and is brought round (or ascends) in such a manner as to peculiarly evert the aperture, and to bring the latter's outer margin right up to the suture, reminding one of the genera Boysia, Scopelophila, &c.; looking at it from behind the aperture, it ascends so much that, at its termination, it completely hides the antepenultimate whorl. The aperture is much everted, triangular, somewhat contracted by the strong inflection of the outer margin above the middle, caused by the impressed dividing groove of the last whorl. Long. 3}, diam. 2 millim. Type, Indian Museum, Calcutta ; also in coll. M M . Bourguignat, Williams, Fagot, Joly, and God win-Austen. CLAUSILIA (DELIMA) PUNCTATA, Michaud. A rather uncommon and almost invariably broken subfossil form from deposits A, B, C, D. M. Bourguignat found it living in the Col di Tenda. CLAUSILIA (DELIMA) VIRIATA, Bourg. (Hist. Claus. France, 1877, from the Col di Tenda.) Though almost exactly of the same proportions as the preceding, a totally distinct species, it is quite impossible to confuse the two. This form occurred subfossil, with the preceding, in deposits A, B, and C; they are still to be found living together in the Col di Tenda. CLAUSILIA (PAPILLIFERA) SOLIDA, Drap. An abundant species from the immediate proximity of the sea up to some 2000 ft.; at the higher elevations on the " Grand Mont," &C. Cl. solida does not exist, indeed Mr. Williams could not find there any representative of the genus, although he searched specially for them. The numerous varieties of this form are some of them very interesting; and the whole group requires special study. I think there can be no doubt M . Bourguignat was right in specifically separating one or two of them. Unfortunately it is quite impossible to identify these closely allied forms without first-rate figures I noticed that the variety living near the sea had a much darker Animal than the form I found high up at the village of Roquebrune. 1/ |