50 



MYTILUS siiblrevis. 



TAB. CCCCXXXIX.— /</. 3. 



Spec. Char. Oblong triangular; rather curved; 

 disk obscurely keelshaped ; front straight- 

 ish; beaks acute; lines of growth rather 

 prominent. 



Jl he beaks of this are more pointed than those of the 

 common Mussel ; it is also flatter towards the front and 

 anterior side ; the hinge line is straight, half the length 

 of the shell. 



Very imperfect specimens occur in the Cornbrash 

 limestone at Felmarsham. 



