EXPLANATION OF PLATE XLIV. 



Page 



FIG. 1. Myalina subquadrata 118 



la. Interior of valve. 

 Ib. Exterior of same. 



Carboniferous, Upper Coal Measures. 



FIG. 2. Myalina subquadrata 118 



2a. Outside of valve. 

 2b. Inside of same. 



Carboniferous, Upper Coal Measures. 



