162 BIVALVES. 



They live buried under the sand, but select a 

 spot within reach of the waves, as they require 

 frequent supplies of water, and to obtain it, are 

 continually protruding their tubes. Many of 

 the species afford nutriment to the poorer classes. 

 The name is derived from the Greek naflta, 

 (cardia) a heart. 



CARDIUM Edule* 



COMMON COCKLE. 



Specific Character. Shell convex, sometimes 

 produced at the posterior end, with about twenty- 

 six longitudinal ribs and transverse wrinkled 

 striae, which in old specimens appear somewhat 

 imbricated ; colour whitish, or pale ferruginous ; 

 about an inch and a quarter long, and an inch 

 and a half broad. 



This species is very common in most of our 

 inlets and bays near 'the mouth of rivers, where 

 the shore is sandy. They are fonnd buried three 

 or four inches under the surface. The mollusks 



when boiled, afford a wholesome nourishment. 



i 



CARDIUM Tuberculatum.^ 



TUBERCULATED COCKLE. 



Specific Character. Shell somewhat orbicular, 

 ponderous, slightly truncated at the anterior side, 



* Edule, eatable, from the Latin ed ere, to eat. 

 t Plate VIII. figure 2. 



