116 SPECIES OF THE SYSTEMA. 
included among the doubtful species of our author. For how 
can any member of a genus so polymorphous as Ostrea, be 
indisputably determined from a most meagre description and 
uncharacteristic figures. 
Ostrea edults. 
The Ostrea edulis of authors (Sow. Genera Shells, Ost. f. 1) 
is marked for this species in the Linnean cabinet. Being 
indicated by Linneus as the edible oyster of Europe, it was of 
course immediately recognised, yet scarcely any characteristic 
representation of it occurs in the works of the older writers. 
Klein’s engraving is copied from Lister (194, f. 31, not quoted): 
the reference to Lister should have been 193, f. 30 (mot 20). 
The figures in both of Lister’s works are known to be designed 
for our British species, and Gualtier’s delineation is not 
unlike it: Ginnani’s drawing is decidedly suggestive of our 
common rock oyster, but that the Adriatic species is really 
identical with ours I hesitate to affirm. The engraving of 
Bonanni is too bad for positive identification: those of Ron- 
delet, &c., are execrable. 
Ostrea semtaurita. 
Even the modern genus in which this species should be 
located is a subject of discussion. The shell which Chemnitz 
has figured for it (Conch. Cab. vol. vii. f. 579) is the Perna 
radiata of Anton (P. vulsella var. of Lamarck): Schréter and 
Gmelin suggest a Crenatula (avicularis ?): Deshayes more 
logically argues for Meleagrina. 
The species is pictorially defined in the tenth edition of the 
‘Systema,’ since the cited figure of Gualtier, which accords 
with the description, is a decided Meleagrina; and, although 
‘the little study hitherto bestowed upon that interesting group 
prevents me from naming it, is apparently a recognisable shell.* 
* Gualtier, for want of a glass, has reversed the valves. His figure closely 
resembles a most variable Jamaica species distributed by the late Professor 
Adams as Avicula (Mel.) crocata. 
