236 THE NERVOUS SYSTEM 



the branches of the neurons which lie in the base of 

 the brain. They then pass along these branches to their 

 fine many-branched tips, where they come into close 

 proximity with the branches of motor neurons. Here, 



PIG. 131. The cranial nerves. (Quain.) 



as in the case of the spinal nerves, the nervous impulses, 

 although on their way to higher sensory centres in the 

 cortex of the cerebrum, are strong enough to excite im- 

 pulses in the nearby motor neurons. These impulses are 

 then transmitted outward along the motor fibres to 

 muscle cells. As a result, the muscles controlled by 



