ON THE MAMMALIAN NERVOUS SYSTEM. 509 



The experiments of BECK, of FLEISCHL VON MARXOW, and of DANILEWSKY in 

 this connection have been referred to in Chapter II., which deals with the history of 

 the electrical method. With reference to these we would here only point out that 

 the experiments of SETSCHENOW, WERIHO, and ourselves, to which in his Polish paper 

 BECK alludes, seem to us to indicate that the observed electrical changes may have 

 their seat in nerve fibres proceeding from or to centres, rather than in any form of 

 central, i.e., corpuscular, nerve mechanism. 



Any electrical changes in the contacts of the electrodes with the cortex might, 

 therefore, be as much caused by the impulses travelling in the subjacent fibres as by 

 changes in the cells or other surface termini. 



The above criticism obviously does not affect the evidence which the presence of 

 definite electrical changes offers as to localisation, but seems to us to discount any 

 advantage which the method might offer for the investigation of the functions of a 

 nerve centre by the study of the actual changes in its cells. 



SUMMARY. 



It is obviously impossible to formulate with sufficient accuracy many general 

 conclusions as to the mode in which the functional activity of the spinal nerve centres 

 is generated and discharged, but we cannot refrain from pointing out that the 

 electrical method supplies many ways of investigating this very important and 

 difficult subject, and further that it throws most unexpected light on the obscure 

 questions relating to the working of the several parts of nerve centres. 



Most prominently stand out two principal facts : 



(1.) The kinetogenetic portion* of a spinal nerve centre is probably the afferent 

 side. (See Section 2.) 



(2.) The part in which the delay and diminution of impulses passing through is 

 effected is the efferent side of such a centre with the field of conjunction. 

 (See Section 2.) 



The consideration of these facts, unexpected as they were, shows clearly that the 

 interpretation by BASTiANt of sensori-motor nerve phenomena is probably the most 

 correct yet advanced. The basis of that interpretation, namely, the doctrine of 

 kinsesthesis as formulated by him, is in complete harmony with our experimental 

 results. 



BASTIAN has for many years contended that the ordinary division of nerve centres 

 or parts of the same into sensory and motor respectively is misleading, and that not 

 only has the statement that the source of a nerve centre's discharge is the motor part 



* By the term " kinetogenetic portion " we have styled that part of a centre in which the potential 

 energy is converted into kinetic. 



t " The Brain as an Organ of Mind." " Paralysis, Cerebral, Bulbar, and Spinal." 



