EXPERIMENTS ON THE CEREBELLUM 175 



theory that the cerebellum is an organ of coordination 

 is not correct. It may be too that a part of the dis- 

 turbances observed after lesion of the cerebellum are 

 due to secondary effects of the operation on the med- 

 ulla or the corpora quadrigemina. 



This latter conception is supported by comparative 

 physiology. In fishes and frogs, in which the shock- 

 effects are slight, the cerebellum can be removed 

 without producing any disturbance in the behaviour 

 of the animals (Vulpian, Steiner). In sharks, whose 

 cerebellum is strongly developed, I myself have made 

 numerous division-experiments and numerous experi- 

 ments on partial or total extirpation of the cerebel- 

 lum, and no change whatever took place in the 

 behaviour of the animals. It is impossible and un- 

 justifiable in this case to talk of a definite " function " 

 of the cerebellum. 



It may be well, in consideration of what has been 

 said in the preceding chapter and of observations 

 which will be discussed later on concerning the results 

 of lesions of the cerebral hemispheres, to remind the 

 reader of a hypothesis made by Magendie. He saw 

 animals walk or fly backwards permanently after les- 

 ion of a certain part of the medulla oblongata. He 

 saw further that a lesion of the corpora striata pro- 

 duces an impulse to run forwards. Finally he ob- 

 served the rolling motions of the animals about their 

 longitudinal axis after one-sided lesion of the pons. 

 He makes the following remark in this connection : 

 " Comme notre esprit a besoin de s'arreter a certaines 



