PARALYSIS FROM DISEASE OF THE CEREBELLUM. 391 



the cord are directly or indirectly involved. 1 As far as the 

 physiology of the cerebellum bears upon this point, there is 

 no reason why simple disease of its substance should produce 

 hemiplegia. As in cerebral affections disease of the hemi- 

 spheres is followed by hemiplegia, as the rule, only when the 

 corpora striata, the optic thalami, or the pons, is involved, 

 either by compression or disorganization, so in disease of the 

 cerebellum, there must be some disturbance of the motor 

 tracts. 



It is a curious fact, also, that in certain cases of disease 

 of the cerebellum, without any affection of the cerebrum, in 

 which hemiplegia exists, the paralysis occurs on the opposite 

 side of the body, while in others, it is on the same side as the 

 cerebellar lesion. According to Yulpian, the hemiplegia is 

 direct or crossed, the situation of the paralysis depending 

 upon the parts of the motor tracts that are compressed. In 

 simple softening of the substance of the cerebellum, as we 

 have just remarked, there is, of necessity, no paralysis, but 

 haemorrhage or tumors may impinge upon one or another 

 of the motor tracts of the encephalon or the cord. 8 



In certain of the cases collected by Andral, there was a 

 lesion of one lateral lobe of the cerebellum, associated with a 

 lesion of the cerebral hemisphere of the opposite side. In 

 these cases, the paralysis did not affect both sides of the body, 

 but was always situated on the side opposite to the lesion of 

 the cerebrum, the same side as the cerebellar disease. 8 



AVe have thus only discussed those views with regard to 

 the functions of the cerebellum which are supported by ex- 

 perimental or pathological facts, and have not touched upon 

 the vague and unsupported ideas advanced by various writers 

 before the publication of the remarkable observations of 

 Flourens. There is 110 proof that the cerebellum is the organ 



1 YCLPIAN, Systeme nerveux, Paris, 1866, p. 608. 



2 TULPIAX, loc. cit. 



3 ANDRAL, Clinique mtdicale, Bruxelles, 1834, tome v., p. 481. 



