60 



The fiiell is mottled, with rufous-brown and yellow, thin> 

 and nearly fmooth, but not glofly : it has feven rounded rays, 

 not much elevated : the ears are nearly equal, and large, one 

 is reticulated, the other only ftriated. The infide is fingu- 

 larly marked with twenty one flender rays, the fixteen 

 middle ones are placed in fours ; that is to fay, there are 

 four rays between the fulci that form the rays on the outfide, 

 and the two middle of thefe feries of quadruplicate rays 

 approximate ; the others are remote : the colour is paler 

 than the outfide, except at the upper part about the hinge. 

 Length three quarters of an inch, breadth rather lefs. 



Mr. Pennant gives his (hell fifteen faint rays. In the 

 fpecimen before us there is fome flight appearance of inter- 

 mediate rays in the depreflions that feparate the evident ones, 

 and which are formed by the fulci between the approximate 

 rays on the infide. The infide of Mr, Pennant's Ihell is 

 defcribed to be " marked with rays, divided by a fingle 

 /ulcus." What the author could intend by that defcription 

 appears inexplicable ; but that he did obferve an unufual 

 ftrudlure in that part of the fliell feems evident ; upon the 

 whole therefore we do not hefitate to confider it to be that 

 fpecies fo long in obfcurity, and fo much fought after by 

 collectors. 



Thofe who are fortunate enough to obtain this fliell will 

 obferve by the affiftance of a pocket lens, that it is moll mi- 

 nutely llriated concentrically, but does not poflefs any lon- 

 gitudinal7?/'/(P, like P. obfoktics, 



Ostrea 



