Class VI. MYA. GAPER. 159 



Sect. II. BIVALVE SHELLS. 



GENUS IV. MYA. GAPER. 



Animal, an Ascidia. 



Shell gaping at one end. 



Hinge, for the most part, furnished with a 

 thick, strong, and broad tooth, not in- 

 serted into the opposite valve. 



M. Truncata. Lin. Syst. 1 1 12. 



Lisi. Angl. tab. v. Jig. 36. 



1. TRUN 



Gm. Lin. 3217- Fuun.Suec. 



Lin. Tr. viii. 35. 



CATA. 



No. 2126. 



Mont. Test. Br. 32. 



abrupt. 



M. with a broad, upright, blunt tooth, in one 

 shell ; the closed end rounded ; the open end 

 truncated, and gaping greatly ; the outside yel- 

 low, marked with concentric wrinkles; length 

 an inch and an half, breadth three inches. 

 Tab. xliv. 



Lodged under muddy ground, near low- water 

 mark ; discovered by an aperture in the slime, 

 beneath which it is found in coarse gravel. 



