THE FACIAL. 541 



most quadrupeds, at the point of exit of the nerve from the stylomas- 

 toid foramen, or, as practised by Bernard, during its passage through 

 the aqueduct of Fallopius, by means of a cutting instrument intro- 

 duced into the cavity of the tympanum, thus reaching the nerve through 



Fig. 176. 



DIAGRAM OP THE FACIAL NERVB AND ITS DISTRIBUTION. 1. Facial nerve at 

 its entrance into the internal auditory meatus. 2. Its exit, at the stylomastoid foramen. 

 3, 4. Temporal and posterior auricular branches, distributed to the muscles of the external 

 ear and to the occipitalis. 5. Branches to the frontalis muscle. 6. Branches to the stylohyoid 

 and digastric muscles. 7. Branches to the upper part of the platysma myoides. 8. Branch 

 of communication with the superficial cervical nerve of the cervical plexus. 



its upper wall. The effect of this section is to paralyze at once all the 

 superficial muscles of the face on the corresponding side. The visible 

 effects vary in the different facial regions, according to the function of 

 the muscles which have lost their power of motion, 



Effect upon the Eye. The orbicularis* oculi being paralyzed, the eye 

 upon the affected side cannot be closed, but remains permanently open ; 

 even, according to the observation of Bernard, while the animal is 

 asleep. This depends upon the fact that the two muscles serving to 

 open and close the eyelids are animated by two different nerves ; the 

 levator palpebrae superioris, which lifts the upper eyelid, being supplied 

 by the ocnlomotorius, while the orbicularis oculi receives its nervous 



