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Show 1880.] LAND-SHELLS OF MENTON. 113 species is found near Menton, is interesting, as the different forms seem to be fairly constant in their several localities. On the sunny hill of Grimaldi a true dwarf form is abundant, living with a similar dwarf variety of H. vermiculata. Round Menton generally, and up to a considerable height, it is an ordinary form ; near the summits of the mountains, at 3000-4000 feet, it is a gigantic tumid form, not very common, reminding me very much of Algerian specimens. I could see no trace of the species in the lower strata of the " Couche Marneuse " of Cape Mortela (zone of H. paretiana) ; a rather large form abounded, however, at about 5 feet or so below the surface, with other common existing shells of the country. Subvar. nana. Alt. 21|, diam. 25 millim. Found only on the hill of Grimaldi. Subvar. alticola. Alt. 43, diam. 46| millim. Summits of the neighbouring Alps, and a similar, somewhat smaller form from near the surface of the " Couche marneuse " of Cape Mortela. Typical, form. Alt. 30|, diam. 31 millim. Abundant everywhere near Menton, up to about 2000 feet. Measurements below, from Pfeiffer, Mon. i. p. 241 :- Diam. maj. 41, min. 32, alt. 32 millim. B. minor- diam. maj. 28, min. 23, alt. 22 (spec. Azor.). HELIX (POMATIA) APERTA, Born. This is a small form, to be found here and there round Menton ; by no means common. Alt. 21|, diam. 19| millim. Submaritime zone, Menton. Subvar. ampla. I found one or two specimens only, near the surface of the " Couche marneuse " of Cape Mortela; like the preceding, it does not appear to exist lower down, in the zone of H. paretiana. Alt. 29|, diam. 26 millim. Below I give measurements of Pfeiffer, in Mon. i. p. 25 :- Alt. 27, diam. maj. 26 millim. HELIX (MACULARIA) VERMICULATA, Miiller. An ordinary form ; is plentiful all round Menton up to a certain altitude, beyond which it does not appear to exist. It is also common, near the surface only, in the " Couche marneuse " of Cape Mortela. Alt. 22, diam. 2 9 | millim. Var. GRIMALDIENSIS, nov. A remarkable dwarf form, apparently constant, as I found some hundred specimens on the hill of Grimaldi, all in the same locality. Spire varying, but usually more produced than in typical form; last whorl more rounded, scarcely subangulate, more convex at base; aperture less produced, with the columellar margin less oblique and more callous; very variable in its coloration, if any thing a trifle smoother, thicker, and more callous. Type of var. Alt. 17|, diam. 2 2 | millim; another specimen, alt. 16, diam. 2 1 | millim. I found, near Roquebrune, a single specimen, some feet below the P R O C . Z O O L . Soc-1880, No. VIII. 8 |