THE HEAD AND NKCK. 37 



and at the same time cut the skin, fasci.i, and gland substance, in the direction 

 of the branches, with scissors. You will find dissection of this nerve somewhat 

 difficult the first time you make the trial. Any amount of advice, added to 

 what has previously been said, will not help you. Just be careful, and expose 

 one branch at a time. 



Communications of the Facial Nerve on the Face with other Nerves 

 (Fig. 15): 



1. The seventh nerve + mental branch of the fifth nerve at mental foramen. 



2. The seventh nerve -j- infraorbital branch of the fifth nerve at infraorbital 

 foramen. 



3. The seventh nerve i supraorbital branch of the fifth nerve at supraorbital 

 foramen. 



4. The seventh nerve + auriculo-temporal branch of fifth on temporal muscle. 



5. The seventh nerve + malar branch of temporo-malar of fifth nerve on 

 malar bone. 



6. The seventh nerve -j- temporal branch of temporo-malar of fifth nerve 

 above zygoma. 



J. The seventh nerve -f- great auricular nerve of cervical plexus behind the 

 ear. 



8. The seventh nerve -i small occipital nerve of cervical plexus behind the 

 ear. 



9. The seventh nerve + lachrymal and infratrochlear branches of the fifth 

 nerve. 



10. The seventh nerve j great occipital. Posterior division of second cer- 

 vical nerve. 



It will appear from the foregoing that the nerve-supply of the face is a very 

 complicated proposition. Such, however, is not the case, since the whole nerve- 

 distribution can be reduced to : 



1. Motor nerves to the muscles of expression = seventh nerve. 



2. Sensory nerves to the skin over the muscles = fifth nerve. 



3. Sympathetic nerves the nervi molles on facial artery. 



4. Communicating branches to adjacent areas. 



Divisions and Facial Branches of the Facial Nerve. The nerve divides 

 into two branches : (i) An upper division that supplies the upper half of the 

 face and the temporal region ; (2) a lower division that supplies the lower 

 half of the face and the neck. (Fig. 16.) 



The temporo-facial division gives off : 



1. Temporal branches to the temple and forehead. 



2. Infraorbital branches below the orbit. 



3. Malar branches to the zygomatic muscles. 

 The cennco-facial division gives off : 



\. A buccal branch to the buccinator muscle. 



2. A supramandibular branch above the jaw. 



3. An inframandibular branch below the jaw. 



The name pes anserinus is applied to the divergence of these six nerves from 

 the two primary divisions of the seventh nerve. 



The auriculo-temporal nerve will be found in front of the ear just behind 

 the temporal artery. It is a sensory branch of the fifth, and supplies the side of 

 the scalp and the external in front with sensation. 



Find these arteries on the face (Fig. 1 7) : 



1. The frontal in the inner angle of the orbit. 



2. The nasal above the tendo oculi. 



3. The lachrymal in the outer angle to the upper lid. 



4. The transverse facial on the malar bone. 



