THE VOLUNTAKY ARC 



415 



however, that the production of the impulses is essentially 

 the same as in the simpler case. 



The reflex arcs of the cranial nerves are similar in action 

 to those of the cord, and involve sensory and motor 

 neura. Inasmuch as in this action the impulse travels in 

 a circuit, the name of reflex arc has been given to such 

 arrangements as above. 



The voluntary arc. — When we come to examine what 

 takes place in a voluntary action we find that the process 



Fig. 196 — The voluntary arc. 



is not very different from that of the reflex action, except 

 in the time required for transmission. Figure 196 shows a 

 typical voluntary arc. In such a circuit the path of the 



