79 



CULTELLUS, Schumacher. 



Gen. Char. An equivalved, inequilateral, trans- 

 verse, compressed shell, with slightly g-apino-, 

 seldom truncated sides. Hinge-teeth in the 

 right valve, two, one longitudinal, erect, the 

 other (posterior) oblique, decumbent; in the 

 left valve, three, the central one bifid with 

 divaricating apices, fulcrum long, marginal. 

 Beaks distant from, but nearest to, the ante- 

 rior extremity. Epidermis strong. 



More or less oval, transversely elongated, generally 

 shining, tender shells, with the beaks at about one-third the 

 width from the anterior extremity. This genus includes 

 the shells arranged by De Blainville under the third divi- 

 sion of his genus Solenoacrtics, and the first section of his 

 genus Solen. But the characters of the hinge are sufficiently 

 alike in all the species we know to connect them, althouo-h 

 their forms are various. 



CULTELLUS cultellatus. 

 TAB. DCXLII.— /g^. 5—8. 



Spec. Char. Shell elongate-ovate, with obtuse, 

 slightly gaping sides, smooth ; beaks one-third 

 the width of the shell from the anterior ex- 

 tremity, dorsal and basal margins arched; 



