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Show 1880.] LAND-SHELLS OF MENTON. 97 due east; we found the shells here in the deep cutting of the high road under the larger boulders, about the level of the road, buried beneath approximately 20 feet of the Conglomerate; the mollusks were indubitably living here in situ. B. Underneath the railway viaduct, almost exactly in front of the first cavern, something like J 00 metres west of the tunnel, and about the same distance east of the Gorge St. Louis (frontier), about 20 metres above the sea. After passing through the arches, one finds before one a small amphitheatre, in which these shells can be found, here and there, in astonishing profusion. As a rule the Conglomerate here, under which they are buried, is of no great thickness, doubtless owing to the very steep incline of the slope ; under one enormous rock, in especial, we collected a really wonderful number both of species aud specimens. Our researches were so extensive here that we ended by dislodging the boulder itself, my friend having had a narrow escape of being crushed on the occasion. The aspect is due south, and completely protected both from the north and east by the lofty surrounding cliffs in which the caves have been excavated at some remote period ; the humidity of this spot must probably have been very considerable, owing to the small streams that doubtless trickled from the caves immediately above. The mollusks lived here also in situ. C. Deposit, with a southern aspect, a little more to the east than the preceding and somewhat lower down, a few feet only above the sea, in a cutting of the new road which is being made along the seashore for working a stone-quarry, on the sea front of the tuunel. The Conglomerate, above the shells, was here about 20 to 30 feet in thickness. I am not sure that the mollusks lived on this spot. D. Deposit, with a northern aspect, in a cutting of the railroad, about a quarter of au hour's walk to the east from the preceding, about a hundred yards east of the tunnel, quite cut off from all the previous localities by the peak, which here projects prominently into the sea, and which is surmounted by the tower and estate of Grimaldi, belonging to Dr. Bennet. This spot must have been very damp and cold, almost entirely shut in to the west and south by the peak, which easily explains the somewhat different " facies " of the extinct shells. Many of the species, abundant in the preceding deposits, are here very scarce, or altogether absent, whilst others, especially species of Hyalina, Campylcea, & c , are to be found in extraordinary profusion, evidently in situ as they lived, filling the crevasses of the larger blocks of stone, at a depth below the surface of about 15 feet. One or two of the forms also, as Pomatias and Clausilia, though closely allied, appear to be specifically distinct. W e also discovered a few specimens of Hyalina, Pomatias, Helix niciensis, &c. a little more to the west, quite close to the perpendicular sides of the peak itself. E. Bed, or deposit, near the sea and adjoining the stone-quarry, of doubtful age. The mollusks were here evidently not living in situ ; the shells are very difficult to extract from the hard compact mass in which they are imbedded. Most of them belong to the same fauna PROC. ZOOL. S O C - 1880, No. VII. 7 |