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Show 1880.] LAND-SHELLS OF MENTON. 133 Type, Indian Museum, Calcutta; also in coll. J. R. Bourguignat, Coombe Williams, P. Joly, T. Fagot, and Colonel Godwin-Austen. STENOGYRA (RUMINA) DECOLLATA, Linnseus. Abundant everywhere in the submaritime zone. A perfectly similar form also occurred by thousands in the upper stratum of Cape Mortela. I do not believe this mollusk existed at Menton at the time of deposits A to F; but I found a large stout variety always immediately associated with H. paretiana at Monaco, Cape Vieille, lower stratum at Cape Mortela, &c. At this last locality it was very interesting to notice how sharply the upper and lower strata were defined by the very marked difference in this species. The stout big variety from the lower stratum reminded me strongly of specimens I found near Bone, in Algeria. Long. 33, diam. 11} millim. Upper stratum, Cape Mortela, like the existing form. FERUSSACIA GRONOVIANA, Risso1 (as figured by Bourg., diam. 3} millim.) (Plate XIV. fig. 2.) An abundant species here and there in the submaritime zone only. I also found it in great numbers at Alassio. Taking a handful of living specimens from under one stone, the great variability in the shape of the whorls, production of the spire, &c. is at once seen ; still the aperture and last whorl in especial always present certain characters by which the species can be recognized. The animal has the head, top of neck, and both sets of tentacles, also extreme posterior extremity dark green, almost black ; the rest is a very bright greenish yellow. Long. 10, diam. 3% ; another-long. 9, diam. 3f millim. Var. SUBAMBLYA. ? Ferussacia amblya, Bourg. Mai. Alg. (long. 8}, diam. 4 millim. Algiers). This is a short convex form, with the last whorl a good deal more rounded, the aperture less everted, with the columella straight. The whorls increase very slowly and regularly, the difference of the antepenultimate one in this respect, from that of the typical form, being very marked. It may prove a distinct species; but I am inclined to doubt it at present. I only found a few specimens living with typical form. Long. 8^, alt. 3} millim. 1 TAmong the examples of this species given me by Mr. G. Nevill I found a good many were still living; these I closely examined. The animal possesses a well-developed mucus-pore at the extremity of the foot, and therefore belongs to the Stenogyridse of Crosse and Fischer. It is closely allied m its anatomy to the Madeiran form (Lovea tornatellina) described by the Kev. E L . Watson in the P Z S 1875 p. 677, "which is of interest as regards geographical distribution I hope soon to give some details of its anatomy, which I have pre-pared.- H. H . G.-A.] |
