372 NERVOUS SYSTEM. 



following the operation may disappear, and the animal may 

 entirely recover, without any regeneration of the extirpated 

 nerve-substance. This important fact enables us to under- 

 stand how, in certain cases of disease of the cerebellum in 

 the human subject, when the disorganization of the nerve- 

 tissue is slow and gradual, there may never be any disorder 

 in the movements. 



We present the above conclusions, as in our own mind 

 positive and definite. It is proper to state, however, that 

 the definition of the function of the cerebellum is one of the 

 points stated by most physiological authors as doubtful and 

 unsettled ; and this is so, mainly because many writers have 

 been unable to harmonize, the experimental facts above de- 

 tailed, with cases 6f disease or injury of the cerebellum in 

 the human subject. We conceive that this has frequently 

 been due to an imperfect study of the pathological facts, 

 which we now propose to investigate as thoroughly as pos- 

 sible. 



Pathological Facts bearing upon the Functions of the 

 Cerebellum. Nearly all writers on the physiology of the 

 nervous system, while they agree that extirpation of the 

 cerebellum in the lower animals produces irregularity of 

 movements, are arrested, as it were, in their deductions, by 

 the following quotation from Andral, in his report of ninety- 

 three cases of disease of the cerebellum : 



." A more remarkable alteration of movement is noted 

 in the observation of M. Lallemand. The patient staggered 

 on his legs, and often came near falling forward. In this 

 case, the only one which tends to confirm the opinion of 

 physiologists who regard the cerebellum as the organ of 

 the coordination of movements, the cerebellum was entirely 

 transformed into a sac filled with pus." 1 



1 ANDRAL, Clinique medicale, Bruxelles, 1834, tome v., p. 501. 

 The case alluded to is quoted from Lallemand, which we have consulted in 

 the original, and will refer to again. 



