CHAPTER IX. 



The Cerebellum. 



TRANSX^ERSE sections through the cerebellum show 

 the various lobules which cross the median plane, the 

 lohiis ansijormis or cerebellar hemisphere on each side, 

 and the floccular lobe projecting laterally below it. These 

 parts have already been described in the first chapter. Those 

 lobules which are medially situated are best seen in a sagittal 

 section (Fig. 3). Such a section also shows the branching 

 arrangement of the white matter which has received the 

 name of arbor vitae, in which each little branch is one of the 

 transversely disposed lamellae cut across. 



Sulcus primariuj. 

 Lobus 



epyrai 



^^oriulU£ 



Fig. 3 

 Median sagittal section of the cerebellum of the rat. 



In general, the sections of the cerebellum show it to 

 consist of a large mass of white matter, the medulla of the 

 cerebellum, over which is disposed a greatly folded layer of 

 gray matter, the cerebellar cortex. The cortex has a very 

 complex structure, being made up of many different kinds of 



