THE NERVOUS SYSTEM 



125 



ments ; that is, it makes the 

 muscles act at the right 

 time and with due force in 

 complex acts, such as stand- 

 ing, walking, talking. A 

 man could strike just as 

 hard without the action of 

 the cerebellum, but he would 

 not be likely to hit what he 

 aimed at. A drunken 

 man staggers and fails to 

 control the muscles in walk- 

 ing because the alcohol has 

 caused the blood to collect 

 and congest around the 



Cerebrum 



FIG. 114. THE LOBES OF THE RIGHT 

 SIDE OF BRAIN and their functions. 

 (Jegi.) 



The speech center is true only for left-handed 



... 1 X 1IC BUWlrll UCUIAJ 19 II U<- UUtjF WJ" i^ii-Jictli 



cerebellum and press upon persons . M eduiia is marked Bulb." 



it. One whose cerebellum 



has been injured by accident staggers like a drunken man. 



Coverings of 

 the Brain. Lin- 

 ing the skull and 

 covering the cere- 

 brum are found 

 two membranes 

 which inclose a 

 lymph-like fluid. 

 Thus a kind of 

 water bed 'is made 

 which surrounds 

 the soft and deli- 

 cate cerebrum 



FIG. 115. MOTOR AND SENSORY AREAS OF LEFT 

 HEMISPHERE. Speech center marked " Lips." 



protects it 



In what region are the motor centers? The sensory centers? from j a r S. A 



