tiIe 



NATURAL HISTORY 



OF 



BRITISH SHELLS. 



PLATE LXXIIL 



MYA MARGARITIFERA. 



RjyER PEARL MUSCLE. 

 GENERIC CHARACTER. 



Animal an Ascidia. Shell bivalve, gaping at one end. The hinge 

 for the most part furnished with a thick strong broad tooth, not 

 inserted into the oppofite valve. 



SPECIFIC CHARACTER 



SYNONYMS. 



Shell oblong, thick, and covered with a coatse black epidermis, 

 much decorticated or w^orn down about the beaks. A large notched 

 cspnlc cootK in one valve, and two small ones in the other. 



A 2 



