600 THE FUNCTIONAL RELATIONS OF THE 



among higher Vertebrates, so as at last to throw all other divisions 

 of the Brain into the shade. 



There are, therefore, in Vertebrates some fundamental specializa- 

 tions of function, which are, in all probability, carried much larther 

 than in any of the lower animals, the existence of which seems to 

 become marked by the development of parts so distinct morpho- 

 logically as the Cerebral Lobes and the Cerebellum. 



But it is to be regarded as one of the best established of physio- 

 logical facts that the Cerebral Hemispheres or Lobes are the 

 principal organs of Conscious Intelligence — including under this 

 term Sensation and Perception, Ideation and Eeasoning, together 

 with the primary phenomena of Emotion and Volition. The two 

 Hemispheres together, therefore, constitute the supreme organ, the 

 last term of the series of centres, in which 'ingoing' impressions 

 are brought into relation with one another. 



But two things are now almost equally certain in regard to the 

 Cerebellum; first, that it has no appreciable share, as an indepen- 

 dent organ, in the carrying on of any of these processes which, in 

 their totality, are comprised under the head of Conscious Intelli- 

 gence; and, secondly, that its activity is unmistakeably mixed up 

 in some ivay with the animal's power of executing Movements."* 

 In what precise manner it is related to the execution of Move- 

 ments, and to what Movements it is so related, are the problems 

 principally requiring to be solved, and to these subjects we must 

 now turn our attention. 



If we look then to the fact that throughout the ISTervous Systems 

 of lower animals 'sensory' and 'motor' nerve centres exist in corre- 

 lated pairs; if we look to the simultaneous appearance of the 

 Cerebral Lobes and the Cerebellum in the animal series ; if we con- 

 sider that the Cerebral Lobes or Hemispheres have been proved 

 to be the supreme centres for 'ingoing' impressions; and if the 

 Cerebellum has been almost equally well proved to be a great 

 *motor' centre of some kind, it seems a fairly legitimate inference 

 from the foregoing facts that the Cerebellum is the supreme motor 

 centre co-ordinate with the Cerebrum, and that they form the 



* See Owen, " Anat. of Vertebrates," vol. i. pp. 487, 488. The 

 hypothesis of Gall, that the Cerebellum is the seat of the ' sexual 

 instinct,' has little or nothing to be said in its favour which may 

 not be otherwise much better explained (see ' Ferrier's Functions 

 of the Brain," p. 122). 



