CARDITA. 331 



embellisliing his shell with prickly scales^ and that the in- 

 clination ceases when advancing to middle life. Certain it 

 is, that such decorations are found only attached to young 

 shells. 



Great variety prevails in this graceful genus : some are 

 characterized by small zigzag lines ; others are of a deep 

 rose-colour ; in others, again, the rose tint is exchanged for 

 bright saffron-yellow, and a few irregular lines tastefully di- 

 versify the surface. Some species are very numerous ; others 

 isolated, as in the case of the C. Cuvieri ; concerning which it 

 is related by Mr. Broderip that, after the capture of this fine 

 shell in the Bay of Tonseca, Central America, the dredge 

 was kept at work in sandy mud, in eleven fathoms water, 

 during some hours, but no other specimen could be obtained. 

 This species far exceeds in size and beauty any that have 

 hitherto been discovered, and is so exquisitely sculptured 

 with broad and elevated ribs, composed of jointed knobs, as 

 to exhibit almost the appearance of carved work. 



In the C. lacunosa, or Guttered Cardita, the prickly scales 

 which surmount the singularly compressed ribs are placed 

 at equal distances, while each rib is so festooned from one 

 scale to another as to resemble a miniature series of in- 

 verted arches. 



