PLATE CI. 



MYA DEPRESSA. 



DEPRESSED MYA* 

 GENERIC CHARACTER. 



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

 for the most part furnished with a thick, strong, and broad tooth, 

 not inserted into the opposite valve. 



SPECIFIC CHARACTER. 



Somewhat ovate, anterior part rather wedge-shaped and sloping : 

 a slight depression across the middle ; posterior part roundish, gaping. 

 Teeth at the hinge crenulated. 



Mya Depressa : testa subovata, antice sub-cuneiform i declivi, medio 

 depressa, postice rotundata hiante, cardinis dente 

 crenulato. 



After comparing the numerous kinds of fresh water Myas found in 

 different parts of the kingdom, the conchologist will perhaps be sur- 

 prized at the small number we shall venture to admit as distinct 

 species. The varieties of those Shells seem endless, and it may be 



G 4 



