FUNCTIONS OF THE BRAIN. 397 



The exact locality of the sensorium has been eagerly 

 sought for by physiologists in every age. It would appear, 

 from the results of the most recent inquiries, that it cer- 

 tainly does not extend to the whole mass of the brain, but 

 has its seat more especially in the lower part, or basis of 

 that organ. It differs, however, in its locality, in different 

 classes of animals. In man, and the mammalia which ap- 

 proach the nearest to him in their structure, it occupies 

 some part of the region of the medulla oblongata, probably 

 the spot where most of the nerves of sense are observed to 

 terminate. In the lower animals it is not confined to this 

 region, but extends to the upper part of the spinal marrow. 

 As we descend to the inferior orders of the animal kingdom, 

 we find it more and more extensively diffused over the spi- 

 nal marrow; and in the Invertebrata the several ganglia ap- 

 pear to be endowed with this sensorial property: but, be- 

 coming less and less concentrated in single masses, the cha- 

 racter of individuality ceases to attach to the sensorial phe- 

 nomena; until, in Zoophytes, we lose all traces of ganglia 

 and of nervous filaments, and every part appears to possess 

 an inherent power of exciting sensation, as well as perform- 

 ing muscular contractions. 



Beyond this point we can derive no farther aid from Ana- 

 tomy, since the intellectual operations of which we are con- 

 scious bear no conceivable analogy with any of the configu- 

 rations or actions of a material substance. Although the 

 brain is constructed with evident design, and composed of a 

 number of curiously wrought parts, we are utterly unable to 

 penetrate the intention with which they are formed, or to 

 perceive the slightest correspondence which their configu- 

 ration can have with the functions they respectively per- 

 form. The map of regions which modern Phrenologists 

 have traced on the surface of the head, and which they sup- 

 pose to have a relation to different faculties and propensities, 

 does not agree either with the natural divisions of the brain 

 or with the metaphysical classification of mental phenome- 



