124 THE POCKET ANATOMY 



THE CEREBELLUM. 



The cerebellum is contained in the occipital fossae, being 

 separated from the cerebrum above by the tentorium. It 

 consists of two lateral hemispheres connected together by 

 the vermiform process, which projects considerably upon 

 the under surface, forming the inferior vermiform process; 

 but on the upper surface only forms a slight ridge, the 

 superior vermiform process, continuous with the hemispheres 

 laterally. 



The inferior surface of each hemisphere is convex, and 

 between them there is a fossa, the vallecula, at the bottom of 

 which the inferior vermiform process lies, and -which is con- 

 tinuous posteriorly with a notch between the two hemi- 

 spheres. The medulla is in contact with the anterior part 

 of the vallecula, and the posterior part receives the falx 

 cerebelli. 



Laminae and fissures. The surface of the cerebellum 

 consists of lamina, which are separated by sulci or fis- 

 sures. 



The great horizontal fissure divides each hemisphere into an 

 upper and a lower part. It commences at the pons in front, 

 and passes horizontally round the circumference to end at 

 the notch behind. 



Lobes. On the upper surface of the cerebellum are the 

 following lobes : 



(a) Central : a small lobe, forming the anterior part of the 

 superior vermiform process. It is continued forwards on to 

 the valve of Vieussens, forming the lingula (vide roof of 4th 

 ventricle, p. 122), and laterally on to each hemisphere by a 

 winglike fold, the ala. 



(b) Lobus culminis : the culmen monticuli forms the highest 

 part of the superior vermis, and on each side is continuous 

 with the anterior crescentic lobe of the lateral hemisphere ; 

 posteriorly the sulcus preclivalis separates it from 



(c) Lobus clivi : consists of the mesial clivus monticuli, connect- 

 ing on either side the two posterior crescentic lobes, which are 

 broad. 



(d) Lobus cacuminis : behind the sulcus postclivalis, con- 

 sists of a single folium of the superior vermis, folium cacu- 

 minis, connecting the large postero-superior lobes of the lateral 

 hemisphere. 



