160 SENSORIAL FUNCTIONS. 



members of the Mammalia tribes. The Porpoise is 

 also another of this class. These animals are obliged 

 of course, to come up to the surface to breathe, the ac- 

 tion called spouting being merely the expiration of the 

 air from the lungs, preparatory to the inspiration of an- 

 other portion, and by which a quantity of water is 

 thrown above the surface. 



PART V. 



SENSORIAL FUNCTIONS. 



THE Sensorial Functions are those which belong to 

 the brain, as the general source of sensation and per- 

 ception. The systems we have heretofore been occupi- 

 ed in describing, consisting of the Mechanical and Ani- 

 mal Functions, are only the foundations of the higher 

 order of faculties which animals, and especially man are 

 destined to exercise. 



Brain and Nerves. The functions of sensation, per- 

 ception and voluntary motion, require the presence of 

 an organized animal substance, which is endowed with 

 very remarkable properties, and which is known to 



What are sensorial functions'? What is the foundation of the sensorial 

 functions *? 



