GASTEROPODA. 71 



C. Testa minima, cylindracco-turritd ; anfractibus planiusculis ; cingulos tres granosos 

 ferentibus ; basi lavi, canali brevissimo. 



Shell small, subcylindrical, and turriculate ; volutions flattish, covered with three 

 transverse granular ridges ; base naked and smooth, with very short canal. 



Axis, 5- of an inch. 



Locality. Cor. Crag, Sutton. Recent, British Seas. 



An abundant shell, and very variable in its proportional dimensions : some are 

 tapering and elongate, exceeding in length its diameter at least four times ; while 

 others are nearly half as broad as they are long. It is distinguished by having 

 three sharp ridges of tubercles, and a fourth ridge, which is smaller, without the 

 tubercles, at the base, or rather edge, of the last volution. A canal is formed at 

 the suture by the elevation of the tubercular ridges. The base is generally naked, 

 smooth, and flat ; but in some there is a thick and elevated spiral ridge, behind 

 which is a deep sulcus. Cer. pygmceum, Phil., looks like one of its varieties, and 

 the Belgian shell I imagine, from the figure, to be the same. I have fragments 

 which indicate a length of at least three eighths of an inch. 



5. Cerithium metaxa (?). Belle Chiaje. Tab. VIII, fig. 6, 6 a. 



Murex metaxa. Bel. Chi. Mem. 1826, p. 211, t. 49, fig. 29-31. 

 Cerithium creperum. S. Wood. Catalogue 1842. 



C. Testa minima, cylindraceo-turritd ; anfractibus convexis, numerosis ; cingulos granu- 

 losos quatuor ferentibus ; basi lavi; labro acuto ; canali brevissimo. 



Shell minute, turriculate, and subcylindrical ; whorls numerous, convex, orna- 

 mented with four transverse granulated ridges ; base smooth ; outer lip sharp, with 

 very short or emarginate canal. 



Axis, § of an inch. 



Locality. Cor. Crag, Sutton. 



This is not a very abundant shell, and the specimens are generally broken. It 

 appears, however, to differ specifically from C. luberculare in always having four 

 ridges of granules upon the spire, with a smaller one around the base ; the form of 

 the volution is convex, with the lower portion projecting a little, which gives it a 

 subconoidal form. It appears to correspond with the description given by Delia 

 Chiaje, but I am not acquainted with the shell he describes. It differs also, I con- 

 ceive, from C. variculosum in being much more elongate, and by having a deeper 

 suture, and fewer costas. In C. variculosum there are eighteen costee in the last 

 volution ; in this they are from ten to twelve. In the figures these characters are 

 not sufficiently distinguished. 



6. Cerithium cribrarium. S. Wood. Tab. VIII, fig. 7, a — b. 



Cerithium cribrarium. S. Wood. Catalogue 1842. 



C. Testa minima, subulatd, elongatd, tenui ; anfractibus numerosis, convexis, cingulis 

 quatuor ornatis, longitudinaliter decussatis ; basi lavi ; canali brevissimo. 



Shell minute, tapering, and elongate, thin, and fragile, with numerous convex 



