The File Shells 



of the left valve. Through the opening made by this marginal 

 angle, the byssus passes out. Length, 4 to 5 inches. 



Habitat. — Norway. 



The Rough File Shell (L. scabra, Dillw.) has its ridged 

 surface set with small pointed scales, and covered with a yellow- 

 ish epidermis. The shell is comparatively thick and ovate, with 

 the large, anterior ears reflected. Length, 2 to 4 inches. 



Habitat. — Southern Florida, West Indies. 



The Frilled File Shell ( L. squamosa, Lam. ) has it? 

 rounded ridges decorated with erect, flat, scaly plates. The 

 general outline of each valve is obliquely ovate. The ears are 

 small and depressed, the hinge oblique. Length, i to 3 inches. 



Habitat. — Red Sea, Mediterranean, West Indies, Philippines. 



-:io 



