64- MEMOIRS OF 



ations ; on the other hand, organised bodies, 

 composed of a tissue of fibres and plates, the in- 

 tervals of which are filled with fluids, resolve 

 themselves almost entirely into volatile sub- 

 stances, sj^ring from bodies similar to themselves, 

 from which they are only separated when they 

 can act by their own strength, assimilate tliem- 

 selves incessantly with foreign substances, and, 

 introducing these substances between their par- 

 ticles, increase by internal force, and at length 

 perish by this internal force, by the effects 

 even of their vital principle. To originate in 

 generation, to increase by nutrition, and to end 

 by death, are the general and common charac- 

 ters of all organised bodies ; but if several of 

 these bodies only exercise these and their neces- 

 sary functions, and have only the organs requi- 

 site for this comparatively limited part in cre- 

 ation, there are many others which exercise 

 peculiar functions, which not only require organs 

 particularly adapted to them, but induce a mo- 

 dification in the general functions. Of all these 

 peculiar functions, feeling and moving at will 

 are the most remarkable, and most influence the 

 other functions. Independent of tlie chain 

 which links these two fliculties, and the double 

 set of organs which they require, they yet carry 



