CHAPTER XXIII 

 THE CEREBELLUM AND THE BULB 



The cerebellum Physiological anatomy Extirpation of the cerebellum Pathological ob- 

 servations The bulb Physiological anatomy Uses of the bulb Nerve-centres in 

 the bulb Respiratory centre Vital point (so called) Rolling and turning move- 

 ments following injury of certain parts of the encephalon (forced movements). 



THE CEREBELLUM 



A FULL description of the anatomy of the cerebellum is not necessary 

 to a comprehension of its uses, so far as these are known. The points, 

 in this connection, 

 that are most im- 

 portant are the 

 following': the di- 

 vision of the sub- 

 stance of the cere- 

 bellum into gray 

 and white matter ; 

 the connections be- 

 tween the cells and 

 the fibres ; the con- 

 nections of the 

 fibres with the cere- 

 brum and with^cer- 

 tain prolongations 

 of the columns of 

 the spinal cord 

 through the bulb ; 

 and the passage of 



Fig. 147. Cerebellum and bulb (Hirschfeld). 



i, i, corpus dentatum ; 2, pons Varolii ; 3, section of the middle pe- 

 duncle ; 4, 4, 4,4, 4, 4, laminae forming the arbor vitas; 5, 5, olivary body 

 of the bulb ; 6, anterior pyramid of the bulb ; 7, upper extremity of the 

 spinal cord. 



fibres between the two lateral lobes. These are the only anatomical 

 points that will be considered. 



Physiological Anatomy. The cerebellum, situated beneath the oc- 

 cipital lobes of the cerebrum, weighs about 5.25 ounces (148.8 grams) 

 in the male, and 4.7 ounces (135 grams) in the female. The propor- 

 tionate weight to that of the cerebrum is as i to 8f in the male, and as 

 i to 8^ in the female. It is separated from the cerebrum by a strong 

 2 Q 593 



