CARDIUM. COCKLE. 29 



rounded, very rugged with tubercular wrinkles : color 

 yellowish-brown, with often pale and chocolate-brown bands 

 and markings, generally of a deep chocolate-brawn about 

 the margin and anterior side, and of a milky whiteness 

 about the posterior protuberance : beaks very prominent 

 .find nearly central ; inside glossy, with a fawn-color or 

 fleshy tinge ; the grooves on the inside reaching only about 

 half way up the shell : diameter sometimes above three 

 inches. 



It is much larger than C. echinatum, and so ponderous 

 that one of them will outweigh three of the latter of the 

 same size ; the tubercles are never produced into spines, 

 and the anterior slope, when viewed in front, is remarkably 

 flattened and regularly ribbed, in which state it is repre- 

 sented in our figure, v. v. 



Cardinal nodosum. Montagu, p. 81. The young shell. 



Shell flatter than the young of C. echinatum, more re- 

 gularly orbicular, of a reddish colour, with often darker 

 bands ; the tubercles are closer and more obtuse ; the ribs 

 are more rounded ; and it is thicker and stronger. We have 

 this species in all its gradations of size, and can therefore 

 have no hesitation in combining them together. 



On the South Devon coast, v. v. 





3. Cardium echinatum. TJiorny Cockle. 



Lister, pi. 324. f. 161 Da Costa, pi. 14. f. 2 Donovan, 

 pi. 107-f. \ -Dorset Cat. pi, 6. f. 2-JVood, pi. 49. f. 1, 2. 



Shell very convex, a little produced but not flattened on 

 the cartilage side, rounded on the other, with from eighteen 

 to twenty ribs clothed with sharp white enamelled spines, 

 which when viewed sideways resemble fine teeth ; these 

 are often much curved towards the produced side, while 

 those near the hinge are of a longitudinally lance-shaped 

 form : color dull rusty brown more or less mixed with 

 white, with often deeper belts ; inside, glossy white : dia- 

 meter about two inches and a half. 



Cardium ciliare. Pennant, pi. 53. f. 2 Donovan, pi. 32. 

 f. 2 Dorset Cat. pi. 4. f. \fPood^ pL 49. f. 3, 4. The 

 young shell. 



Shell nearly globular^ not produced on the cartilage side, 

 ^ very thin and transparent, with the spines ajl flat 

 jj 3, and 



