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Show 140 MR. G. NEVILL ON THE [Feb. 17, ultimo sat ventricosa, albidula, olim passim fusco flammulata, costata (costce paralleloe, sat distantes, validce in anfractibus medianis, in ultimo strictce, magis approximates, ac prope aperturam evanescentes); spira aeuminato-producta; apice lavi-gato, obtuso, mamillato ; anfractibus 10, convexis, lente crescen-tibus, sutura profunda separatis ; anfractibus medianis leviter tumidis; ultimo vix majore, rotundato, ad aperturam undique dilatato ac expanso, et ad insertionem labri ascendente ; apertura fere verticali, rotundata, exacte pervia, superne vix sub-angulata; peristomate acuto, intus profunde leviterque incras-sato ac fere undique expanso, marginibus callo junctis, margine columellari valde auricula to ac refiexo; operculo ignoto. "Alt. 10, diam. 4 millim. "Couche a Helix paretiana, dans la tranchee du chemin de fer, au Cap Vieille, entre Roquebrune et Monaco." 1 found this species rather scarce in deposit D. My limited knowledge of the European species of this genus hardly entitles me to pronounce an opinion about it; I will only say that my subfossil form from deposit D is indubitably, specifically, quite distinct from that which abounds in the other deposits, and which M . Bourguignat informs me is the Pom. septemspiralis. I am further indebted to m y distinguished friend for informing me, in lift., that Pom. her-culteus is most nearly allied to Pom. simonianus, from which it can be distinguished by its greater size, stronger and more regular sculpture, different coloration (approximating much nearer to that of Pom. septemspiralis), more regularly acuminate spire, less convex whorls, with suture less distinct, by its more ample aperture, " s'epa-nouissant a l'instar du pavilion d'un cor de chasse, &c." Type in coll. cl. Bourguignat; also Indian Museum, and Coombe Williams, Esq. CYCLOSTOMA ELEGANS, Miiller. Living specimens of this widely distributed species are to be found near Menton, here and there, from the neighbourhood of the sea up to some 2000 feet at least. Mr. Williams did not bring me back any specimens from the higher altitudes. A single specimen m}r friend found on the summit of the Grand Mont was a quite different species (probably C. sulcatum, var.), closely allied to the also undoubtedly distinct (from C. elegans) subfossil forms from the zone of H. paretiana and deposits A, D, &c, identified for me by M. Bourguignat as his C. lutetianum and C. physetum. Certain subfossil specimens I found in the couche marneuse of Cape Mortela, in the upper stratum [that is, zone of H. aspersa, H. vermiculata, H. cespitum, &c], show how difficult all these forms are to correctly classify. M. Bourguignat regards them also as belonging to his C. physetum and C. lutetianum. I am convinced they are merely subvarieties of C. elegans, and specifically quite distinct from their above-quoted older relatives. Alt. 14}, diam. 10}; apert. (cum. marg.) alt. 7, lat. 6\ millim. A living specimen of the ordinary type. |