&2 SPECIES OF THE SYSTEMA. 
‘Systema,’ corroborates the ordinary identification ; for where 
doubt exists it is expedient to prefer the established conclu- 
sion. The recorded locality, which, perhaps, resulted from the 
supposed identity of these essentially distinct forms, is not 
suited to our British shell: it is not, however, authenticated. 
SP ON DY EUs: 
In our author’s proposed new edition of his ‘Systema,’ the 
words “alterius truncata nate” were designed to have been 
inserted after the “Testa ineequivalvis, rigida” of the generic 
definition. 
Spondvlus Gesaropus. 
The number of species delineated in the several works 
originally referred to for the synonymy of this shell, and 
which alike answer to the too succinctly comprehensive defini- 
tion of it in the ‘Systema,’ became still more augmented in the 
final edition of that work; for in the quoted plates of Seba 
nearly all the Spondyli may be found delineated. Should 
we search the pages of the ‘Museum Ulrice’ for some limita- 
tion to the looseness of the meagre definition, we shall find 
that the engravings in the three illustrative works there men- 
tioned do not harmonise with each other; even the account 
of the colouring (‘‘ varietate infinita ludens”) and armature 
(‘‘spinas varias—acutas aut planas”’’) argues that our author 
included several shells, now held distinct, under one specific 
epithet. In this predicament, naturalists have reasonably 
given to the recorded locality the unwonted weight of a 
limiting characteristic, and, thus restricted, the sifted synonymy 
yields to us the Mediterranean Spondylus universally recognised 
as Gedaropus (Poli, Test. Sicil. vol. ii. pl. 21, f. 20, 21). That 
