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Show 1880.] LAND-SHELLS OF MENTON. 101 bouring peaks, the "Grand Mont" (4475 ft.) and the "Berceau" (3575 ft.), which were attended with very marked success. A considerable number of the subfossil species which I found in the deposits of m y so-called "Cave period," have been discovered living at high elevations in the surrounding Alpes Maritimes, both by Mons. Bourguignat and now by Mr. Williams-such as H. olivoluta, H. diceya, H. niciensis, Pupa obliqua, Hyalina maceana, Clausilia punctata, viriata, and bizarellina, &c.; doubtless many of the others will eventually be also discovered. When one attains a height above the sea of approximately 1600 feet or so, Clausilia solida and Rumina decollata appear to reach their limit, and Zonites algirus, H. obvoluta, &c. appear for the first time. A little higher still occurs a fine stout variety of H. niciensis, H. (CampyIcea) cingulata, var., and H. nemoralis ; here, too, a very large, smooth and rounded variety of H. cespitum takes the place of the small, compressed, striate submaritime variety (or distinct species ?) ; H. cemenclea the place of H. anconce ; Hyalina eugyrus and H. maceana the place of the very distinct species of Hyalina abundant near the sea all along this part of the Riviera. Approaching the peaks of these Alps, one meets with various forms of Fruticicola (section Zenobia), Pomatias patulum, Torquilla avenacea and secale, gigantic varieties of H. aspersa and H. nemoralis, a thin, very variable, and poorly-coloured variety of H. niciensis closely resembling the subfossil variety from the " Balzi Rossi," Cyclostoma. physetum, Sue. T E S T A C E L L A WILLIAMSIANA, n. sp. (Plate XIII. fig. 1.) T. crassa, cretacea, subplanata, ovata, subemaciata, ad basim cequa-liter anguste attenuata rotundata, supra striis incrementi con-centricis valide ac subconfertim sulcata; apex exacte centralis, fere rectus, subverticalis, acute prominens ; columella crassa, haud plana, perarcuata, superne conspicue intorta, inferne obsolete truncata; peristoma leviter arcuatum ; superne, ad apicem termi-nans, lunula triangularis ac profunde incisa existat. Long. 5, diam. 2 | millim. Of this small species I only found seven specimens, all slightly differing in size (ranging from 4 to 5f millims.); Mr. Coombe Williams, after whom I have named the species, also found about six or seven, which, unfortunately, I have not been able to examine. W e only found the species in Deposit B, nowhere else. It is next allied to T. bisulcata, Risso, admirably figured by Bourguignat in his ' Moll. Alpes-Marit. publies par Risso,' from which it is well characterized by its peculiarly regular and attenuately compressed ovate form, by the perfectly rounded, instead of angulate, base, by the slightly though distinctly more arcuate peristome, by the more arcuate and twisted columella less distinctly truncate at base, but above all by the remarkable, almost vertical, and acutely prominent apex, perfectly central, instead of being a good deal everted, and |