1864.] 



177 



April 7, 1864. 



Major-General SABINE, President, in the Chair. 



The Rev. Dr. Salmon was admitted into the Society. 



The following communications were read : — 



I. On the Functions of the Cerebellum." By William How- 

 ship Dickinson, M.D. Cantab., Curator of the Pathological 

 Museum, St. George's Hospital, Assistant Physician to the Hos- 

 pital for Sick Children. Communicated by Dr. Bence Jones. 

 Received March 8, 1864. 



(Abstract.) 



The paper is divided into two Parts ; the first gives the results of expe- 

 riments on animals ; the second, of observations upon the human being. 



Part I. 



Assuming that the great divisions of the brain preserve each the same 

 function through the vertebrate kingdom, it is maintained that experiments 

 which can be performed only on such of the lower animals as are very 

 tenacious of life, will afford deductions of universal appHcation. 



The method of proceeding with regard to each species was to remove, 

 first, the whole encephalon, with the exception of the medulla oblongata ; 

 then in a similar animal only the cerebrum was taken away. The only 

 difference between the two cases was in the fact that one animal had a 

 cerebellum, and the other had not. A comparison was believed to show, in 

 the powers which one had more than the other, the function of the organ 

 the possession of which constituted the only difference. 



Finally it was ascertained in each species what is the effect of taking 

 away the cerebellum alone. 



The use of the organ was thus estimated in two ways — by the effect of 

 its addition to the medulla, and of its subtraction from the rest of the 

 nervous system. 



The species so treated are arranged in an ascending scale, according to 

 the comparative weight of the cerebellum. The field-snake, frog, sala- 

 mander, toad, land-tortoise, eel, water-tortoise, pike, perch, tench, dace, 

 carp, gold-fish, rudd, loach, and gudgeon were subjected to these opera- 

 tions ; besides which, many experiments of a less systematic character were 

 made upon birds and mammalia. 



The results are these : — 



In Reptiles, with the exception of the snake, the cord, together with the 

 medulla oblongata, is sufficient to give the power of voluntary or sponta- 

 neous motion — limited, but usually enough to allow of feeble locomotion. 



With the addition of the cerebellum, all actions dependent on the will 

 appear to be naturally performed. 



vol. XIII. p 



