PLAT. 't. 
FIG._O. 
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. Sool. No. 66. tad. 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 purplisli 
brown, with numerous fine longitudinal strie *, 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 strie; this appears 
however, to be an error of the engraver. 
