276 SPECIES OF THE SYSTEMA. 
“labri margine attenuato,” though possibly meant only to con- 
trast the lip itself with the expanded and lobated form of that 
part in its congeners, has probably misled naturalists; the 
edge of the outer lip in the type, however (Sow. Thes. Conch. 
vol. i. pl. 7, f. 45, but not so distinctly banded), is actually 
attenuated. 
Stronmus Dentatus. 
Linneus did not himself possess this species, which although 
too briefly characterised, cannot well be mistaken, since of no 
other Strombus than one can the lip be declared toothed and 
peculiarly short. That shell, indeed, the S. tridentatus of 
Lamarck (S. dentatus, Sow. Thes. Conch. vol. i. pl. 9, f. 86, 87) 
possesses all the required features, which, upon the whole, are 
so peculiar, that, had it not been for the idea that “labro 
attenuato” was equivalent to “labri margine attenuato,” its 
identity would probably have suggested itself to all naturalists. 
Tiamarck erred doubly; he termed plicatus the very shell he 
had declared to be the dentatus of Linnzus; and selected, as 
the representative,of the Linnean species, a Sirombus that does 
not even exhibit the peculiar features from whence the specific 
appellation was derived. 
Strombus tubereulatus, 
It was in the twelfth edition of the ‘Systema’ that the 
S. tuberculatus made its first appearance, but being briefly 
characterised, and unillustrated by any pictorial synonym, 
much uncertainty has accrued as to the shell intended. The 
Cerithium (for its generic position was not doubtful), supposed 
by Born to be identical, did not even fulfil the few require- 
ments of the short diagnosis, the spiral elevations being hori- 
zontally compressed large black knobs, instead of horn-coloured 
(“ punctis corneis”) smaller ones. Gmelin copied the words 
of the ‘Systema,’ but referred to Born’s plate, as well as the 
other engravings cited by that writer. I observed in the col- 
lection of Linneus a shell, which answers so correctly (and 
