418 SPECIES OF THE SYSTEMA. 
Batella sacchavina. 
It matters little that no specimens can be discovered in the 
collection of Linneus which alike suit both his description 
and synonymy of this limpet, since naturalists have almost 
universally selected as its representative the shell (Patella 
saccharina of Lamarck, figured in List. Conch. 582, f. 10) 
delineated in the majority of the cited engravings. Among 
these, however, Gualtier’s must be reckoned a doubtful repre- 
sentation. 
From the passage “radius 7, ad 11—interjectis dentibus 7 
minoribus alternis” in the ‘Museum Ulrice,’ one is led to 
suspect that the species so designated in that publication was 
either an extreme variety or essentially distinct. It may pos- 
sibly, indeed, have been the former, since individuals are 
occasionally met with that have alternating finer riblets, and 
although the decided ribs more frequently amount to seven 
only they are not absolutely limited to that number. 
In the revised ‘Systema’ “532, f. 10” has been substituted 
for the previous circuitous mode of referring to Lister’s 
* Historie,’ a style necessary, indeed, from the absence of 
numerals upon the plates of the earlier edition of that valuable 
iconography, but apt to mislead, since the copper-plates are 
known to have been arranged variously in different copies, and, 
being so small that several were inserted in the same page, 
have been sometimes reckoned as component parts of one large 
* tabula.” 
Patella barbara. 
Marked examples of this shell (Humphrey’s Conch. pl. 4, 
f. 16, admirably) are still preserved in the Linnean cabinet, and 
answer adequately to the published description. They are 
identical with the Patella spinifera of Lamarck, as figured by 
Delessert, of which I regard the Cypria of Gmelin (Martini, 
Conch. i. pl. 9, f. 79) and the barbata of Lamarck to be mere 
varietal forms. . 
