TURBO. 
99 
still it is, or ought to be, without the slightest an- 
gularity. Much as the cancellate and tapering 
sections differ in outward properties of figure from 
the preceding divisions, yet the internal chamber 
is equally round and entire in all. There does not 
appear, therefore, any just reason for separating 
from the genus those species which are not defec- 
tive in the principal generic character laid down ; 
but some approach too near the Helix and other 
tribes, to remain unmolested in their present situa- 
tion. Doubtful species, of which there are unques- 
tionably but too many, must be learnt by expe- 
rience only. The exact limits of each genus should 
be well understood, and then no great inconveni- 
ence can arise from the errors of a catalogue.' 
The name of this genus is as closely connected 
with that of its predecessor, as are the individuals 
which severally compose them ; Turbo signifying, 
like Trochus, any thing which whirls round, a top. 
Both genera are found among the rocks on craggy 
shores, and on the sands, after a storm has 
detached them from their accustomed refuge. 
