AOS: SPECIES OF THE SYSTEMA. 
tolerably well), a Mediterranean shell that agrees with the 
description in the ‘Systema,’ and with the cited figure P of 
Gualtier’s folio; the queried C of the same publication, though 
rather an ambiguous portraiture, recals to mind the aspect of 
the species, and may have been engraved from a worn example. 
A very different limpet, with blunt ribs in place of raised 
narrow stria, and of great magnitude (“caput infantis superans ”’) 
was subsequently described in the ‘Museum Ulrice ;’ but the 
definition of it was so imperfect that Menke (Nov. Holl.) and 
Reeve (Conch. Icon.) have selected two utterly dissimilar shells 
as its representative. 
Watella fusca. 
To identify the Patella fusca of Linneus, from so meagre 
and unillustrated an account as he has furnished us with, was 
so hopeless a venture that most naturalists have either con- 
tented themselves with reproducing the original description or 
have passed by the species in silence. Born and Dillwyn, how- 
ever, fancied that they had detected the features of it in the 
P. Magellanica, a limpet which, as Schréter has justly remarked, 
differs widely in characteristics from those specified in the 
‘Museum Ulrice.’ Even the “‘striis elevatis” of the single 
line of description in the ‘ Systema’ would not be appropriate ; 
and assuredly the ‘ cinereo—nigricans, radius tenuissimis fili- 
formibus cinereis” (M. U.) is utterly opposed to its peculiar 
colouring. 
The marked example (plate 4, f. 9) in the cabinet of Linneus 
enables us to say what species was recognised by Linneus him- 
self as the Patella fusca. The specimen alluded to is that 
variety of the P. argentea of Quoy and Gaimard that is devoid 
of all marbling, and is merely adorned with depressed striz- 
like black ribs. It agrees with the language of the ‘ Systema,’ 
but does not exhibit the “vertex ferme centralis” of the 
‘Museum’ details. Since the species was never adequately 
defined, no claims of precedence can be grounded upon the 
mere preservation of the original specimens. 
