FUNCTIONS OF THE CEREBELLUM. 



197 



267- This table affords us much scope for interesting speculation, and maybe 

 applied to the correction of hypotheses erected upon other foundations. Before 

 we proceed to these, however, a few general remarks may be made upon it. 

 In the first place, the proportional development of the Cerebellum is seen to 

 be smallest in the vermiform Fishes, which approach most nearly to the Inver- 

 tebrata ; but it is much greater in the higher Fishes than it is in Reptiles. If 

 we consider in what particular, that may be reasonably supposed to have a 

 connection with this organ, the former surpass the latter, we should at once 

 be struck with their superiority in activity and variety of movement. Passing 

 on to Birds, we remark that the average dimensions of the Cerebellum greatly 

 surpass those of the organ in Reptiles ; but that they do not exceed those 

 occasionally met with in Fishes. The greatest size is not found in those 

 species which approach most nearly to the Mammalia in general conformation, 

 such as the Ostrich ; but in those of most active arid varied powers of flight. 

 Lastly, on ascending the scale of Mammiferous animals, we cannot but be 

 struck with the rapid advance in the proportional size of the Cerebellum, that 

 we observe, as we rise from the lowest, which are surpassed in this respect by 

 many Birds, towards Man, in whom it attains a development which appears 

 enormous, even when contrasted with that of the duadrumana. 



268. We have next to inquire what evidence can be drawn from Experi- 

 mental investigations on the same subject ; and in reference to this it is 

 desirable to remark, in the first place, that the experimental mode of inquiry 

 is perhaps more applicable to this organ than to other parts of the Encephalon ; 

 inasmuch as it can be altogether removed with little disturbance of the actions 

 immediately essential to life ; and the animals soon recover from the shock of 

 the operation, and seem but little affected, except in some easily recognized 

 particulars. The principal experimenters upon this subject have been Rolan- 



17* 



