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Show 1880.] LAND-SHELLS OF MENTON. 125 everted, with less oblique columella ; it is, however, too close to be separated, even as a variety. Unique (subfossil) specimen in Indian Museum, Calcutta. PUPA (TORQUILLA) QUINQUEDENTATA, Born. Living specimens are most abundant all along the Genoese Riviera, at Monaco, Menton, Alassio, &c. At Menton it is found from the sea up to 2500 feet; after that it becomes much rarer, but exists up to nearly 4000 feet. There is but little difference between the sub-maritime form and that from the higher regions; the latter are generally somewhat smaller. Long. 14^, diam. 4 millim. A fine form from Roquebrune station. Long. 141, diam. 3} millim. A rare and remarkably attenuate var., of 11 whorls, from St. Agnes (2500 feet). Long. 9}, diam. 3^ millim. A common dwarf form from the same spot. Long. 13\, diam. 3 | millim. A common cylindrical form from the " Berceau." Var. PRJEHISTORICA, nov. The commonest subfossil shell in all the deposits except F; though varying in countless ways, it always preserves a distinct "facies" from that of the preceding living form ; it can invariably be distinguished by the much stronger and more regular striation, not so oblique, so flexuous, or so inclined to be subobsolete ; the aperture is also invariably smaller and more contracted, less everted as a rule, with both margins straight and parallel, instead of more or less rounded ; the folds appear scarcely to differ at all. Long. 14, diam. 4 millim. Type of the var. from deposit B. Var. SPELTJNCARUM, nov. A more distinct and characteristic variety than the preceding, which I only found in deposit F, where it was abundant, and in tbe interior of the cave itself (as I have already mentioned). A very short, convexly swollen, tumid form, of only 9 instead of 10 whorls, the last being proportionally much broader ; striation more like that of the typical form than of the preceding variety ; the short, quadrangular, unusually everted aperture, with remarkably thickened and reflected peristome, seems to be its most characteristic feature, the margins being more convexly rounded and united by a distinct (instead of subobsolete) callosity ; I can see no difference in the folds (or teeth). Long. 101, diara- H millim. From deposit F. Types of all the preceding in Indian Museum, Calcutta. PUPA (TORQUILLA) MULTIDENTATA, Olivi. =P. variabilis, Drap. Though more localized than the preceding, a very common Menton mollusk, varying enormously in the number and shape of the whorls |