106 



substance of the shell is solid, but thin, foliaceous, and 

 in many species almost transparent. The animal sus- 

 pends itself to rocks or other substances by an abun- 

 dant byssus of a fine silky texture, with which various 

 articles of dress have been fabricated. Shell subequi- 

 valve, flattened, no particular opening for the byssus : 

 hinge lateral, linear, and marginal. 



A most singular and elegant species of Pinna exists 

 in the late Earl Tankerville's cabinet, having each 

 valve on the hinge side strongly serrated longitudinal- 

 ly, and in many other peculiarities differing from any 

 species hitherto described. 



Pinna rudis Pinna muricata 



flabellum pectinata 



seminuda saccata 



angustina varicosa 



nobilis dolabrata 



squamosa ingens 



marginata vexillum 



Pinna nigrina. 

 [And one fossil species.] 



