324 SPECIES OF THE SYSTEMA. 
SGrochus perbersus. 
One of the marked receptacles in the Linnean cabinet (the 
inscribed characters, however, rendered illegible by time) con- 
tains the Cerithiwm perverswm of the ‘ Animaux sans Vertébres,’ 
a shell (Payraud. Cat. Moll. Corse, pl. 7, f. 7, 8) ordinarily and 
not unreasonably identified with the present species. ‘The 
language, ‘“ duplici serie excavato-punctatis, preter margines 
anfractuum etiam crenato-punctatis,” is by no means suitable 
to express a sculpture consisting of three series of spirally- 
arranged granules: its origin is, however, explained by the 
state of our author’s specimens, in which the smaller central 
grains are so far worn down to a level surface that the minute 
intervals between the rows look like punctures, whilst the 
coarser series of the upper and lower granules preserve more 
of their pristine appearance. As these specimens agree 
the best of those present in the cabinet, and our author has 
noted their forming part of his collection, I regard their 
presence as confirmatory of the admitted (though hitherto 
somewhat problematical) identification. 
Trochus ptiuctatus. 
Nothing in the Linnean cabinet answers precisely to the 
description of this shell. The two species which approach 
nearest to the indicated characteristics are the Cerithiwm 
lactewm and the C. lima of Bruguiére (C. reticulatum of British 
writers), the former of which, being white, does not suit the 
expression “ ferruginea,” the latter, having four rows of equal- 
sized raised dots, does not correspond with the passage “ serie 
triplici (punctorum), quarum intermedia minor est.” The 
C. tuberculare of our shores possesses the ascribed character- 
istics; I dare not, however, assert it to have been the T'rochus 
punctatus of Linneus, although the locality (for it is found, 
also, in the South of Europe) likewise coincides, since Philippi, 
in the ‘ Zeitschrift fiir Malakozoologie’ for 1848 (p. 23), has 
