39 



referee! to three figures in Chemnitz, one of which apper^rs 

 to 'be of a different genus, and very diflimilar to ihe otlicrs ; 

 and in order to add to the confufion, has sfiven two fliells 

 under the title of V.CiVicellat.T, for the latterof which. No. c)6, 

 he quotes Lister. 



Mr. Donovan, as we before remarked, has given a Ihell 

 under this title, and it will be feen that we hazarded 

 an opinion, that fuch might pofTibly be the young of V\ 

 venucofd ; if however the fhell here defcribcd fliould prove 

 to be the cancelUta of that author, v/e flioukl be extremely 

 happy to corred; the error j but as far as we are able to 

 colledl from the materials before us, confiderable doubts 

 muft flill exill in our m nd whether it really is the cancelLta 

 of either of the authors we have here referred to. Pofhbly 

 it may be the Peclunculus membranaceus of Da Costa. 



Shell ovate, with )iumerous concentric laminal ridges, very 

 little reflefted ; thefe ridges are not quite regular nor equi- 

 diftant, but fo thin as to be almoft membranaceous ; between 

 the ridges about the umbonal region, where a natural de- 

 cortication has taken place, it is finely ftriated in the longi- 

 tudinal direcliion, which fliews that younger fpecimens 

 are more generally furniflied with [vichjiriie ; but in the only 

 large fpecimen we have had an opportunity of examining, 

 fcarcely any fuch markings were obferved, but where the 

 old fliell had been fuperficially feparated : the umbo is pointed 

 and much reclined to one fide, beneath which is a broad 

 cordiform depreffion ; but neither this, nor the cartilage 

 flope differs in colour from the rell of the flicll, whicli is 



wholly 



