72 MOLLUSCA FROM THE CRAG. 



volutions, ornamented with four or five elevated transverse ridges, decussated by 

 elevated lines of growth ; base naked ; canal very short. 



Axis, f of an inch. 



Locality. Cor. Crag, Sutton. 



A few imperfect specimens of what I had considered in my Catalogue as a dis- 

 tinct species are in my cabinet ; they appear to differ from the preceding in the 

 absence of the granules upon the transverse bands ; it is possible it may be only an 

 altered form, although at least twenty fragments present the same characters ; but 

 better specimens are necessary for such a determination. Its present name may 

 therefore be considered only as provisional. 



7. Cerithium perpulchrum. S. Wood. Tab. VIII, fig. 10, 10 a. 



C. Testa parvd, conico-titrritd, vel subulatd ; spird elevatd ; apice acuminato ; an- 

 fractibus 10 — 11, convexiusculis, cingulos tres vel quatuor obtusos ferentibus, interstitiis 

 fenuissime striatis, longitudinaliter obsolete plicatis ; labro subsinuato ; canali brevissimo. 



Shell small, elongato-conical, or turriculate, with an elevated spire, and acute 

 apes ; volutions slightly convex, furnished with three or four obtuse transverse 

 lidges, having fine striee between them, obsoletely plicated longitudinally ; canal 

 very short ; outer lip subsinuated and slightly recurved, with a somewhat expanded 

 inner lip. 



Axis, -| an inch. 



Locality. Cor. Crag, Gedgrave. 



One specimen in my own cabinet, and two from that of Mr. Daniel, are all that 

 I have seen, and these are somewhat in an altered condition, with a slightly eroded 

 surface. It bears a resemblance to C. turritellatum, Deshayes (Coq. foss. des Bnv. 

 de Paris, p. 415, pi. 49, f. 10 — 11), but is much more tapering in form, with rather 

 less convex volutions, and has more distinct longitudinal plicae, produced by a 

 slight reflection of the outer lip ; the two ridges of the lower part of the volution 

 are the most prominent, particularly the one around the edge of the base. The 

 lower part of the outer lip is a good deal expanded, and the inner lip considerably 

 spread. It is a pretty shell, and I was unwilling it should be unfigured, but, 

 like the preceding one, better specimens are necessary for correct determina- 

 tion. 



Sect. (3. SINISTRAL. 



8. Cerithium adversum. Mont. Tab. VIII, fig. 8, 8 a. 



Murex adversus. Mont. Test. Brit. p. 271, 1803. 



Cerithium adversum. Brown. Illiist. Brit. Conch, pi. 48, fig. 64 (male), 182". 



— S. Wood. Catalogue 1842. 



Triforis adversa. Loven. Ind. Moll. Scand. p. 21, 1846. 



C. Testa minutd, subcglindricd, sinistrorsd ; anfractibus planis, cingulos tres granosos 

 ferentibus ; apice acuto ; canali brevi recurvo, snbclauso. 



