79 

 gles exteniinp; later^illy from these ara the cross-bars for the 

 wirss. The sires to be supported, following out our compar- 

 ison, ara the horizontal axones of the granular neurones, which, 

 as *fe have already noted, extend through the molecular layer 

 in large numbers. 



5. Arshi tea twe and Phijsioloqu of the Cerebellum. 



It is now a veil established fact that the principal func- 

 tion of the cerabsllJTi is to preside over the equilibration of 

 the body. Moreover, a fairly direct connection is traceable 

 between the morphology of this segment of the brain and the 

 nature of the muscalar activities -vhich are characteristic of 

 the animal. To the student of comparative neurology, there- 

 fore, the cerebellum holds problems of a special order, and 

 is ever potential with no mean interest. 



We have seen that the cerebellim of Wustelus retains an 

 external form of a far lower order than that found in the bird 

 or mammal. The internal organization is not so inferior, howev- 

 er, as we might, from this fact, be led to infer. The archi- 

 tectural features of the lower and the higher types are so 

 similar that the contrast is really one of degree and not one 

 of kind. In both instances, the same sorts of neurones are 

 present, grouped in a similar way, and related to each other 

 physiologically in essentially the same connections. This 

 remarkable identity of features can only be interpreted to mean 



