THE BRAIN 125 



On the under surface of the cerebellum are the following 

 lobes from before backwards : 



(a) Lobus noduli, comprising the nodule of the inferior vermis 

 and the flocculus of each side, with a delicate connecting white 

 lamina, inferior medullary velum. 



(b) Lobus uvula. The uvula forms a considerable part of 

 inferior vermis , it is connected by a low ridge, the furrowed 

 band crossing the sulcus valleculae, with the prominent tonsil 

 or amygdala. 



(c) Lobus pyramidis : the prominent mesial pyramid con- 

 tinuous laterally with the biventral lobes. 



(d) Lobus tuberis : comprises the tuber valvula, which is 

 the posterior part of the inferior vermis and the postero- 

 inferior lobes of the lateral hemisphere; the latter is sub- 

 divided into lobus gracilis in front and inferior semilunar lobe 

 behind. 



STRUCTURE. 



White matter : in each hemisphere there is a central white 

 mass, containing in its middle a grey nucleus, the corpus 

 dentatum. 



The white centre sends processes into the laminae, and is 

 prolonged anteriorly into the crus cerebelli, which divides 

 into three peduncles, viz. : 



Superior peduncle : passes to the base of the corpora quad- 

 rigemina and cerebrum. 



Connecting the bases of the two superior peduncles is the 

 valve of Vieussens. 



Middle peduncle (the cerebellar commissure) : forms the 

 transverse fibres of the pons. 



Inferior peduncle : connects the cerebellum with the medulla 

 and cord ; it passes downwards at the back of the medulla, 

 forming the restiform body. 



The white matter in the vermiform processes consists 

 of a central part, projecting into the laminae of the pro- 

 cesses. 



Anteriorly it is continued into the inferior medullary 

 velum. 



Grey matter of the hemispheres : 



A cortical layer : forming a continuous covering of the cere- 

 bellum. 



