PLATE L 



FIG. II. 

 PECTEN OBSOLETUS. 



GENERIC CHARACTER. 



Ostrea. Linn. 



SPECIFIC CHARACTER 



AND 



SYNONYMS. 



One large striated ear, with smooth equal shells ; eight obsolete 

 rays; of a dark purple colour. Penn. Br. Zool. No. 66. tab. 61. 

 fig. 66. 



Pecten Parvus : parvus fuscus longitudinaliter striatus, Da Costa. 

 Br. Conch. 153. 8. 



This is a very rare species ; da Costa received his specimen from 

 Cornwall. 



The valves are equal and shallow ; the shell thin, and semitranspa- 

 rent ; the ears unequal, one being very small. The inside is smooth 

 and brown, with a pearly gloss. The outside is a dull purplish 

 brown, with numerous fine longitudinal strias *, eight or ten of 

 which are more prominent than the rest. These are surely not the 

 obsolete rays of Pennant, as da Costa imagines ; the former author 

 must allude to the intermediate rays which are depressed and appear 

 worn, as he describes them. 



* The figure in Pennant's work is represented with transverse striae ; this appears 

 however, to be an error of the engraver. 



