324 NERVOUS SYSTEM. 



ments, the action was always crossed. It was also found that, 

 after severe haemorrhage, the excitability of the cerebrum 

 quickly disappeared, which may account for the negative re- 

 sults obtained by previous experimenters. ~No motor prop- 

 erties were found in the posterior portion of the cerebrum. 1 



The experiments just cited throw a new light upon the 

 properties of the cerebral substance. It has always been found 

 difficult to experiment upon the great encephalic centres 

 without disturbing the physiological conditions so seriously 

 as to render the results of direct observations of this kind 

 more or less indefinite. Now that it is ascertained that, in 

 all probability, these centres readily lose their normal prop- 

 erties as a simple consequence of haemorrhage and exposure 

 of the parts, we are less disposed to accept the older experi- 

 ments, in which the cerebral tissue was apparently shown to 

 be incapable of receiving direct artificial impressions. There 

 can be scarcely any doubt with regard to the positive results 

 obtained by Fritsch and Hitzig ; and it is by no means im- 

 probable that further investigations may show that other 

 parts of this centre are excitable. For the present, we can 

 only accept the definite conclusions drawn by these physiolo- 

 gists from their direct experiments, admitting that we are 

 prepared to learn, from further observations, that other parts 

 have analogous properties. 



Functions of the Cerebrum. 



The history of the functions of the encephalon belongs 

 without question to physiology, and is one of the most exten- 



1 FRITSCH TJND HITZIG, Utber die electrische ErreglarJceit des Crrosshirns. 

 Archiv fur Anatomic, Physiologic, und wissemchaftliche Mcdicin, Leipzig, 1870, 

 S.' 300, el seq. 



In the London Lancet, October 21, 1871, No. xvii., p. 581, is a note stating 

 tkat the experiments of Fritsch and Hitzig have been confirmed by Schiff. Schiff 

 is of the opinion, however, that the movements produced by stimulation of the 

 brain-substance do not depend upon direct excitability of the brain, but are re- 

 flex, the result of irritation of parts concerned in tactile sensibility. As far as 

 we know, the experiments of Schiff have not yet been published in full. 



