881 



White, rather more straightly pyramidal than C. trilineatum, 

 less so than C. terebelhmu In both these the ribs are narrower 

 than the interstices, but in C. cereum the reverse is the case. 

 Mr. Hanley's collection, from Australia. 



143. Cerithium ASsiMiLATUM (pi. clxxxiv. f. 246), C.B. 

 Adams, Shells of Jamaica. 



Cerith. testa nigi-escentc, C. terebello simih, sed costis sub- 

 tuberculatis ; anfractibus medianis subinflatis, basi subrotundatis. 



A darkly coloured Jamaican shell, like C. trilineatim m form, 

 and showing three ribs on each of the upper whorls, but these are 

 slightly tuberculated. 



1 e. Rather rounded aperture, granulated whorls, short, groove- 

 like canal. — Genus Pirenella, Gray. 



144. Cerithium attramentarium (pi. clxxxv. f. 249, 250), 

 A. Adams. Lampania attramentarium, A. Ad. ined. 



Cerith. testa subpyramidah, nigrescente seu nigro punctata, spi- 

 raliter crebre sulcata; anfractibus prope suturam albis, apicnli- 

 bus subplanulatis, medianis gradatim paululum inflatis ; apertura 

 simphci, subovali ; labio interno paululiim calloso ; columella tor- 

 tuosa ; canaH vix distincto ; labio externo undato. 



In several specimens we have seen, the top whorls are straight, 

 while the lower ones are bulged out a little below, towards the 

 suture; this may be characteristic, or merely accidental. The 

 shell is pyramidal, typically of a dark colour, although in a variety 

 light and dark spotted. It is spirally grooved, and the outer hp 

 is thin. Mr. Cuming's cabinet, Locahty unknown. 



145. Cerithium subviride (pi. clxxxv. f. 247), Nobis. 

 Cerith. testa C. attratnentario simili, sed pyramidal!, breviuscula, 



sulcis creberrimis, anfractibus hand inflatis, ad suturam nigro 



A single specimen of this species is in Mr. Hanley's collection. 

 It resembles C\ attramentaria, but the whorls are more straight^ 

 and the upper part of the whorls is marked by a variegated band 

 of dark colour, instead of being white. The specimen figured is 

 Mr. Hanley's. 



146. Cerithium undulatum (pi. clxxxv. f. 248), Nobis. 

 Cerith. testa C. attramentario simih, sed anfractibus ad su- 

 turam nigris, elevatis, undulatim crenulatis. 



It is darkly coloured, elevated, and undulated on the upper 



