152 SUPPLEMENT 
class of this great group, which he still named white blooded 
animals, and which were soon to be known by the denomina- 
tion of invertebrata, characterized them in a clear and precise 
manner, as well as the other three, those of insects, worms, 
and zoophytes, which he admits among the animals without 
internal articulated skeleton ; then taking into consideration 
the form of the mollusca, he divides them into three sections, 
cephalopods, gasteropods, and acephala. In the first he 
placed not only the sepia of Linnzus, but also the argonauta. 
But it would be superfluous to enlarge further here on the 
labours of Cuvier. 
M. de Lamarck had chiefly confined his speculations on 
this subject to a consideration of the shells, but in his work 
on invertebrated animals, published in 1801, he has pretty 
nearly followed the example of M. Cuvier. He imitates him 
at first in this, that the class of the mollusca is put at the head 
of the invertebrated tribes. But subsequently he departs from 
his plan pretty often. Thus his first division of mollusea into 
two orders rests on the presence or absence of the head, a 
division which is merely implied in the systems of Poli and 
Cuvier. 
In spite of this evident march towards perfection in the 
classification of the mollusca, some persons even in France 
thought proper to stick to the system of Linnzus, improved 
by Bruguicres: such, for example, was M. Bosc. In his sup- 
plements to Buffon, although he felt the value of the innova- 
tions which had been made, he nevertheless adopted the divi- 
sion of the molluscous worms for the naked mollusca, and of 
testaceous worms for the conchyliferous species; and in each 
of these divisions he exactly followed Bruguiéres, adopting, 
however, the new generic division of Cuvier and De Lamarck. 
M. Bosc, however, who has often had occasion to study living 
mollusca, has introduced many new facts into their history, 
and has also established some genera. 
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