‘ 
i 
A} 
* 
i 
o~, 
Different Ammals, Sc, 4of 
sensible to heat and light and are excited to action 
dy these stimuli.* Here then every part of the 
system has an equal claim to being the seat of 
sensation and volition. 
It is only in the more complicated, or perfect 
animals, as M. Cuvier very justly observes, that 
_ the assemblage of the different parts of the ner- 
yous system and especially the presence of its 
central parts are absolutely necessary for the 
exercise of the functions of this system.t When 
we consider what takes place in polypuses, we 
may be led to conceive, adds this author, ‘“ that 
at the bottom all the parts of the nervous system 
are homogeneous and susceptible of a certain 
number of similar functions, nearly as the frag~ 
ments of a large magnet, when broken, become 
each a small magnet, having its poles and cur- 
rent, and that it is accessory circumstances only 
and the complication of functions, which these 
parts have to discharge in the higher orders of 
animals, that render their concurrence neces- 
sary and occasion each to have a_ particular 
destination.” 
a iia ab Oy expansion des actinies correspond parfaitement 
ala sérénité de l’ air, le polype a bras s’ appercoit tres- 
bien de la présence de lalumiére ; il 1’ aime & il se dirige 
gonstamment vers elle. Ibid. p. 362. 
| Anatom. Comparée, T. II, p. 94 
Ibid, ps 95. ‘ 
