104 MR. G. NEVILL ON THE [Feb. 17, 



Hyalina (Retinella) hercul^a, Rambur (Jourii. de Conchyl. 

 1868, Monaco, and 1869, pi. 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 

 n. 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 Mc/opina, 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 ahjirus ; 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. pare- 

 tiana, 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. herculcea of Rambur. 



The largest form (true Htj. olivetorum fide el. Bourg.) was espe- 

 cially 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. Innately oval, being 

 almost exactly similar ; the spire in the Menton specimens is more 

 depressed, slightly less convex, and markedly more central ; the um- 

 bilicus a trifle less perviously open. 



Alt. 15|, diam. 28 ; apert. alt. 12^, lat. 13 millim. From 

 deposit D. 



Alt. 171, diam. 30; apert. alt. 13|, lat. 1-4^ millim. Specimen 

 from Lucca. 



Var. MACROBiOTUS, nov. (^Hyalina macrobiota, n. sp.). 



A very characteristic and distinct form, from deposits A, B, and 

 J). Easily recognized from type form by the more convex whorls, 

 the last one more abruptly deflected, more convex at base, and espe- 

 cially by its being notably less expanded, thus causing the spire to 

 be markedly less central; the umbilicus is very similar; the aper- 

 ture 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. \^, diam. 261 ; 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- 



