jcardium. '275 



nately and without regard to their natural connexion. 

 The characters assigned by Linne to C. tuberculatum 

 (" sulcis obtusis nodosis transversim striatis ") are more 

 applicable to our shell than those by which C. rusticum 

 is described, viz. " sulcis xx remotis interstitiis rugosis." 

 For the above reasons, and because every writer on 

 European or British conchology, except Poli in the last 

 century and Forbes and Hanley of late years, has applied 

 the name of rusticum to a varietv of C. edule. it would 

 seem undesirable to reject the well-known and appro- 

 priate name of tuberculatum. I may also observe that 

 Mr. Hanley, in his Supplement to Wood's ( Index Tes- 

 taceologicus ' (the publication of which was completed 

 in 1856), regarded the C. rusticum of Linne as "pro- 

 bably a variety of edule " The C. ciliare of Donovan 

 (but not of Linne) and C. nodosum of Montagu (but not 

 of Turton) are the young of the present species. 



4. C. papillo'sum*, Poli. 



C. papillosum, Poli, Test. utr. Sicil. ii. p. 56, t. xvi. f. 2-4. 



Shell very gibbous and nearly globular, with a somewhat 

 oblique outline, solid and opaque, glossy : sculpture, 25 or 2(5 

 flattened ribs, with very narrow furrows or interstices between 

 them ; each rib is furnished with a series of white tubercles, 

 which are conical and more or less incurved on the posterior 

 side, smaller in the middle, and bluntly triangular or calyci- 

 form on the anterior side ; the furrows are crossed and in- 

 dented by numerous regular, narrow slits or punctures : colour 

 yellowish, sometimes variegated by reddish-brown streaks or 

 bands, especially on the posterior side : epidermis fibrous and 

 rather coarse, light yellowish-brown, only observable in the 

 furrows : margins rounded on the anterior side, with an ob- 

 lique slope to the front, which is also curved, and obtusely 

 truncate on the posterior side, which is expanded and twice 

 the breadth of the other side ; a blunt and indistinct angle 



* Covered with papilla 1 . 



