Zoological Society. 443 



on the shores of China, but will not venture to assign it that or any 

 other locality. 



DoNAx CARiNATA. Doti. tcstd elongato-cuneiformi, antice acunii- 

 natd, convexd, purpureo-fuscd, striis longitudinalibus magis mi- 

 nusve distinctis ornatd (sape politd, radiisque saturatioribtis 

 obsolete depictd) ; vulvd oblique truncatd, lateribus carinatd, fer^ 

 planidatd, striisque subgranulatis radicdd ; intus purpured, denti- 

 bus lateralibus in utrdque valvuld duobus, marginibus crenatis. 

 Long. I poll. ; lat. If poll. 



Hab. } Mus. Stainforth, Metcalfe. 



A species peculiarly characterized by the very sharp and subros- 

 trated angle formed by the venti'al edge with the nearly straight 

 edge of the depressed and sharply carinated anterior slope. In the 

 majority of specimens the striae have become obsolete and the shell 

 brilliantly polished. The general outline bears some little resem- 

 blance to that of the true trunculus of Linnaeus, a very different shell 

 from that erroneously but universally so designated by those who 

 have written on British conchology. 



DoNAx DENTiFERA. Dou. tcstd abbveviato-subtriangulari, postice 

 rotundatd, antice obtusd et tumidd, rugis tenuissimis strias longi- 

 tudinales antice decussantibus ; vulvd subbiangulatd, striis tenuibus 

 subgranulatis radiatd, sulcoque dentifero notatd ; margine ventrali 

 vix arcuato ; dentibus cardinalibus et lateralibus in utrdque valvuld 

 duobus ; intus marginibus crenatis. 

 Long, li poll, ; lat. 1| poll, 



Hab. } 



The abbreviated shape of this remarkable shell would alone sepa- 

 rate it from most of the Donaces possessing a crenulated margin. 

 The extraordinary tooth at the extremity of the radiating groove in 

 one valve, which fits into a corresponding notch at the extremity of 

 that of the other, is however its more prominent characteristic. A 

 few teeth show themselves likewise at the extremity of the longitu- 

 dinal elevated striae w^hich margin the anterior slope. 



The colouring is extremely variable, being uniform flesh-colour, 

 olive-yellow, with the umbones violet, or even white. The interior 

 rivals the exterior in the diversity of its tints. 



DoNAx PULCHELLA. Don. tcstd transvcrsim elongatd, convexd, pel- 

 lucidd, politd, postice attenuatd, productd, antice brevi ; obtusd, 

 margine ligamentali valde convexd ; albidd, striis longitudinalibus 

 obsoletis anticeque radiis purpureis angustis tribus ornatd; vulvd 

 lateribus rotundatd, striisque tenuibus radiatd; margine ventrali 

 subrectd, intiis crenulatd ; dentibus lateralibus valde approximatis. 

 Long, i poll. ; lat. -1 poll. 

 Hab. West Indies. 



An exceedingly common species from the West Indies, which, 

 from its apparent similarity with the sculpellum of Gray, has hitherto 

 remained uncharacterized. Its peculiarly transverse shape, its 

 breadth being considerably more than twice its length, sufficiently 

 distinguishes it from any of the named species of this genus, with the 



2H2 



