152 EOCENE MOLLUSCA. 



V. testa ovato-oblongd, costatd, transversim sulcata, antice sub-profunde emarginatd ; 

 spird brevi, acuminata .- anfractibus convexiusculis, una serie spinarum dentiformium 

 coronatis, ad margines suturales planatis ; costis numerosis, angustis, acuti-nodosis, ad 

 basin tendentibus : aperturd elongato-angustd ; labro intus incrassato, plicate- , ad mar- 

 ginem crenulato ; columella triplicatd. 



Shell oblong-oval, ribbed, transversely sulcated, rather deeply notched at the base ; 

 spire short, pointed ; the ribs narrow, rather numerous, extending to the very base of 

 the whorl : whorls rather convex, crowned by a single row of short, erect, sharp tooth- 

 like spines, between which and the suture the margin is flattened, forming a narrow 

 channel or ledge, which runs round the spire and gives a turreted aspect to the shell. 

 The furrows are separated by a narrow line, which rises into small pointed knobs, where 

 it crosses the ribs, and are roughened by numerous sharp, perspicuous lines of growth ; 

 the last furrow, immediately in front of the spines, is wider than the rest. The aperture 

 is long and narrow ; the outer lip thickened, plicated within, and crenulated on the 

 margin ; the inner lip is not much spread over the body whorl, and does not extend 

 backwards beyond the suture. 



In the French shells the ribs are close and broader; the elevated parts, where 

 they are crossed by the furrows, are consequently blunter and more nodiform than in the 

 English shells ; the ribs also, instead of being crowned with erect pointed spines, 

 terminate in thick round knobs, which extend partly over the margin towards the 

 suture, and the outer lip, although thickened, appears to be not plicated within. Dr. 

 Beyrich considers V. lima to be a different species to V. digitalina ; but in all respects, 

 except those pointed out, the two agree so well that, notwithstanding this high autho- 

 rity to the contrary, I regard the French shell as a local variety only of Brander's Bucc. 

 scabriculum. 



The shell from Bracklesham Bay, figured in Mr. Dixon's work (t. 5, fig. 22) as 

 V. crenulata, belongs in fact to this species. Defrance, indeed, suggests that V. scabri- 

 cula may probably be only a variety of V. crenulata, modified by local conditions. 

 It is difficult to ascertain to what extent specific characters may be modified by 

 external conditions ; but the different sculpture, the narrower aperture, the deeper 

 notch, the less effuse inner lip, and the thickened plicated outer lip of the shells under 

 description, appear to me to justify their being retained as a distinct species. 



Size. — Axis, 1 inch and 4-1 Oths nearly ; diameter, 6-10ths of an inch nearly. 



Localities. — Barton, Alum Bay (Stratum No. 29, Prestwich), Highcliff, Bracklesham 

 Bay. French : Valmondois, Betz, Monneville, Tancrou (fide Desh.). 



