54 
MEMOIR OP LAMARCK. 
skin ; the form symmetrical, the parts arranged in 
pairs. The intelligent animals, forming the third 
grand division, feel, and acquire ideas capable of 
being preserved, and execute operations between 
these ideas which furnish them with others; and 
they are intelligent in different degrees. They 
possess a vertebral column, a brain and spinal mar- 
row ; distinct senses ; organs of motion fixed to an 
interior skeleton, and symmetrical forms, the parts 
being placed in pairs*. 
This general distribution of animals has not been 
very much approved of by naturalists ; and Cuvier 
asserts that it is neither founded on their organiza- 
tion, nor an exact observation of their faculties. 
The degree of intelligence observed in the different 
classes, would certainly lead most observers to give 
a very different position to several, from that which 
tli ey have obtained in the above scale. The insecta 
and arachnides, for example, which are made to 
occupy the lowest place among the sentient races, 
are undoubtedly entitled to the rank assigned to 
the mollutca and cirrhipedes ; for there can be no 
comparison in this respect between a hive-bee or an 
ant, and an imperfectly organized and almost inani- 
mate mollusc. 
At a subsequent period, in consequence of some 
new discoveries made by M. M. Savigny, Leseur, 
and Desmarets, he separated certain tribes from the 
polypi, and formed them into a distinct class under 
the name of ascidims. Some new views likewise 
* Animaux sans Vertcbres , i. 381. 
