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Show 880.] LAND-SHELLS OF MENTON. 141 Alt. 16|, diam. 12; apert. alt. 8 (vix), lat. 7 millim. Specimen from upper stratum, Cape Mortela. Identified by M . Bourguignat as his C. physetum, considered by m e merely a form of C. elegans. Alt. 1 Of, diam. 10f, apert. alt. 7, lat. 6} millim. From the preceding locality; identified by M . Bourguignat as C. lutetianum; an elongate subvar. of C. elegans in m y opinion. CYCLOSTOMA SULCATUM (?), Drap., var. (var. reticulata, Zgl.). The single living specimen already alluded to, found at 4000 ft. on the "Grand Mont," is most certainly quite distinct from C. elegans. There are two described species to which it may belong, C. sulcatum or C. physetum; or, what seems to me likely enough, it may be both ; that is, these two species may prove not separable except as varieties. The specimen does not agree exactly with the subfossil ones identified by M. Bourguignat as his C. physetum. To me it seems an extreme variety, differing more from the C. elegans type as to the shorter spire, more convex whorls, and globosely swollen last whorl, but less as regards coarseness of the sculpture; the umbilicus and aperture with its margins seem to be exactly similar. They differ so widely from Algerian specimens of C. sulcatum that I am in doubt whether both ought not to be separated as C. physetum. Unfortunately I have not got with me any typical French specimens of C. sulcatum for comparison. Alt. 16f, diam. 13}; apert. alt. 8}, lat. 7f millim. Unique specimen from the "Grand Mont." CYCLOSTOMA LUTETIANUM, Bourg. Moll. Diluvium, Paris, pl. iii. figs. 35-37, 1869. One of the most abundant shells in deposits A, B, C, D, and E (the genus did not occur at all in deposit F). One of the forms I include under the above heading was invariably to be found where-ever H. paretiana occurred, both at Cape Mortela and Cape Vieille &c, M . Bourguignat identifying it as his C. lutetianum. I did not find in this zone any specimen of what I consider a variety only, and what M . Bourguignat calls C. physetum. In deposits A and D especially these two so-called species, varying in every specimen, and running into one another from the extreme of one form to that of the other, were to be found mixed up together under one rock, leaving in m y mind not the slightest doubt as to their being varieties of one single species, most certainly quite distinct from C. elegans, possibly extreme varieties of the living form C. sulcatum, or perhaps a distinct species. I think they are very doubtfully specifically separable from the preceding living specimen, which, however, I have thought best temporarily to separate as a variety of C. sulcatum. Specimens from deposit D had a distinct tendency to coarser sculpture than those from other localities. Alt. 21}, diam. 14} ; apert. alt. 9, lat. 8} millim. An elongate specimen from deposit D, with the aperture widely detached from the body-whorl. AU. 16}, diam. 12|; apert. alt. 7}, lat. 7 lmlhm. |