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Show 104 MR. G. NEVILL ON THE [Feb. 17, HYALINA (RETINELLA) HERCULEA, Rambur (Journ. de Conchyl. 1868, Monaco, aud 1869, pl. ix. fig. 7, as Zonites sp.). I only found a single, fortunately very perfect, specimen of this rare, well-marked, and very distinct species : I obtained it in the lower stratum of the " Couche Marneuse " at Cape Mortela, zone of H. paretiana. As Mr. Bourguignat's collection, though containing most of Rambur's and Issel's Ligurian subfossil types, did not possess this interesting form, I had much pleasure in presenting him with the above unique specimen. HYALINA (RETINELLA) OLIVETORUM, Hermann (? var. leopol-diana, Charp, MS.). A nice case arises here, with regard to priority of the subgeneric name; which should it be-Retinella, Shut. MS., Fischer, Not. Malac. ii. 1878, or AEgopina, Robelt, Cont. Rossm. Icon. 1878? I have nowhere found this species living in this part of the Riviera, where its place has been apparently taken by Zonites algirus; in former years it evidently abounded : it occurs in deposits A, B, C, E, and by thousands in deposit D (the subgenus not being represented in deposit F). I found it also, immediately associated with H. paretiana, all along the coast, from Monaco to Cape Mortela, at least one other closely allied but distinct species being found with it, only of much rarer occurrence, Hy. herculaa of Rambur. The largest form (true Hy. olivetorum fide cl. Bourg.) was especially abundant in deposit D; it closely resembles specimens I possess from Lucca, the dilatation of the last whorl, its slight compression at the periphery, and shape of the aperture, lunately oval, being almost exactly similar; the spire in the Menton specimens is more depressed, slightly less convex, and markedly more central; the umbilicus a trifle less perviously open. Alt. 15f, diam. 28 ; apert. alt. 12|, lat. 13 millim. From deposit D. Alt. 17\, diam. 30; apert. alt. 13|, lat. 14^ millim. Specimen from Lucca. Var. MACROBIOTUS, nov. (^Hyalina macrobiota, n.sp.). A very characteristic and distinct form, from deposits A, B, and D. Easily recognized from type form by the more convex whorls, the last one more abruptly deflected, more convex at base, and especially by its being notably less expanded, thus causing the spire to be markedly less central; the umbilicus is very similar; the aperture less compressed and higher in proportion, the columellar margin being less oblique. The differences can be easily seen in young as well as in mature specimens. Alt. 15$, diam. 26} ; apert. alt. 12, lat. 12 millim. From deposit D. Subvar. SUBINCERTA, nov. A very curious small form, of which I found some half dozen specimens in deposits B and C only. The spire is unusually ele- |