OSTREA, ear 
f. 27; t. 191, f. 28; t. 192, f. 29—List. Ang. t. 5, f. 30—Gualt. 
Test. t. 73, f. 9” are added for a synonymy by the younger 
Linné, and support the received opinion. The species was 
apparently determined from the details of the ‘Museum Ulrice,’ 
which, at a time when few of the genus Pecten graced the 
cabinets of the curious, were sufficiently antagonistic to the 
features of the other known Pectens to cause its ready deter- 
mination. 
The name opercularis originated from an erroneous belief 
that the paler valve of a Pecten was necessarily the lower, 
and, as the richer coloured valve was more convex than the 
other, it was doubtlessly to draw attention to the circumstance 
that the appellation was bestowed. 
“Scabrities constat squamis imbricatis minoribus O. palli, 
sed radii plures” has been written by our author in his own 
copy of the ‘ Systema.’ 
Ostrea gthba. 
Linneus has not included this species in the list of those 
possessed by himself: there is, however, a single distorted 
valve in the cabinet that is precisely like the one figured in 
the cited engraving of Browne’s “ Jamaica.” 
The remarkably swollen form of both valves has rendered its 
identification as the Pecten thus named by Sowerby (Sow. Thes. 
Conch. vol. i. pl. 12, f. 1) and others to be very generally ap- 
proved of. The “interstitiis angustissimis,” however, of the 
‘Museum Ulrice’ is rather opposed to the received identifica- 
tion. The younger Linné has quoted “ Gualt. t. 278, f. D, L” 
and “ Regenf. t. 2, f. 16” in illustration of this species. 
Ostrea flabvicans. 
Before the publication of the ‘Museum Ulrice’ that work 
was referred to for a description of this obscure species. The 
type or original, then, was in all probability in the Royal 
collection; assuredly nothing in the Linnean cabinet answers 
