ANATOMY AND PHYSIOLOGY OF NERVOUS SYSTEM. 



GSfi 



The peduncles are six in number three on each side. They are 

 known as the superior, middle, and inferior cerebellar peduncles. 



Surface Form. The cerebellum consists of a median lobe (the 

 vermis) and two lateral lobes (the cerebellar hemispheres). The supe- 



vermiform process extends from the notch on the anterior to the 

 one on the posterior border. 



' The under surface of the cerebellum is subdivided into two 

 lateral hemispheres by a depression (the valley}. It extends from 

 before backward in the median line. On the floor of the median lobe 

 is the inferior vermiform process. 



' 



Fig. 274. Horizontal Section Through the Cerebellum. 

 B. STILLING.) 



(After 



The section passes through the region under the corpora quadrigemina (T), 

 then through the anterior cerebellar peduncle (R), and between these through 

 the lingula (A). Above this lies the nucleus tegmenti, nucleus fastigii (m), to the 

 left of the nucleus globosus (Ng), the embolus (Emb), and still farther to the side 

 within the hemisphere the corpus dentatum (Cdc). 



Internal Structure of the Cerebellum. The cerebellum, like the 



)inal cord, is composed of both white and gray substances. The gray 



is the most abundant, and occupies the periphery of the organ in 



the form of a thin layer which is from two to three millimeters in 



thickness. 



The white substance is placed in the center of the organ and is 

 enveloped in all of its parts by the gray matter. The white represents 



