CHAMA HEART CLAM. 171 



a half in breadth. A specimen of this extraor- 

 dinary species, forms a very elegant baptismal 

 font in the church of St. Sulpice, in Paris ; it was 

 presented by the Venetians to Francis I. Large 

 pearls are occasionally found in the Chama ; one 

 exhibited at Sir Joseph Banks', was valued at 

 between two and three hundred pounds. The 

 colour of the Chama Gigas, is a dingy white : 

 the hinge is furnished with a cartilage of a dull 

 colour, which when cut and polished, is as beau- 

 tifully iridescent as Opal. 



CHAMA Cor* 



HEART CLAM. 



Specific character. Shell equivalve, globose, 

 heart-shaped when viewed from the posterior 

 side ; thick, strong, smooth, or only slightly 

 striated transversely : umbones large and promi- 

 nent, apices involute, and turned to one side : 

 colour pale yellowish brown, covered with a 

 darker epidermis, decorticated at the umbones. 

 Shell about three inches long, and two and three 

 quarters broad. 



This shell has but very rarely been found in 

 the British seas ; it is much prized on account 

 of the singular and graceful beauty of its form. 



* Plate IX. figure 3. 



