THE NERVOUS SYSTEM OF MAN. c, 



anterior part of the medulla, and are distributed to the 

 ocular muscles (Figs. 33 and 34). 



5. Trigeminal. — This comes from the anterior portion 

 of the medulla, pierces the skull, and comes out on the 

 face on each side, just in front of the ear. It forms 

 there a ganglion or knob, and then divides into three 

 branches and is distributed to all parts of the face to 

 form the nerves of sensation of the face. It is a morbid 

 condition of this nerve which constitutes neuralgia of 

 the face, or tic douloureux. Fig. 34 shows how a branch 

 of this nerve goes to each tooth. Toothache also is a 

 painful affection of this nerve. 



7. Facial. — This, also originating from the medulla, 

 comes out on the face near the ear and ramifies over 

 the whole face and head. It is the general motor nerve 

 of the face. It controls all the facial muscles, and 

 therefore gives emotional expression. Paralysis of the 

 face is an affection of this nerve. 



8. Auditive. — Coming also from the medulla in close 

 connection with the last, this does not come out on the 

 face at all, but passes immediately into the inner ear, 

 to be distributed there as the nerve of hearing. 



9. Glossopharyngeal (Gustatory).' — It is not quite cer- 

 tain what nerve is the gustatory, but the distribution of 

 this one to the back part of the tongue and adjacent 

 parts of the throat, where the gustatory sense chiefly 

 resides, makes it probable that this is it. The distribu- 

 tion is shown in Fig. 33, page 51. 



10. Vagus or Pneumogastric. — This large nerve comes 

 from the medulla, passes through the base of the skull 

 and down into the thoracic and abdominal cavities, and 

 is distributed to the lungs, the heart, and the stomach. 

 It reports their condition and wants and determines 

 their movements. It is therefore both sensory and 

 motor. 



