EXTERNAL BRANCHES OF THE FACIAL. 163 



is easy to assign to each of what may be termed the external 

 branches of the facial its particular office. 



Just after the nerve has passed out at the stylo-mastoid 

 foramen, it sends to the glosso-pharyngeal the communicat- 

 ing branch, the functions of which we have just considered 

 in connection with the movements of the palate. 



The posterior auricular branch, becoming sensitive by 

 the addition of filaments from the cervical plexus, gives sen- 

 sibility to the integument on the back part of the ear and 

 over the occipital portion of the occipito-frontalis muscle. 

 It animates ( the retrahens and the attollens aurem, muscles 

 but little developed in man, but very important in certain 

 of the inferior animals. It also animates the posterior por- 

 tion of the occipito-frontalis muscle. 



The branches distributed to the posterior belly of the 

 digastric and to the stylo-hyoid muscle simply animate these 

 muscles, one of the uses of which is to assist in deglutition. 

 The same may be said of the filaments that go to the stylo- 

 glossus. 



The two great branches distributed upon the face after 

 the trunk of the nerve has passed through the parotid gland 

 have the most prominent function. Both of these branches 

 are somewhat sensitive from their connections with other 

 nerves, and are distributed in small part to integument. 



The temporo-facial branch animates all of the muscles of 

 the upper part of the face. In complete paralysis of this 

 branch, the eye is constantly open, even during sleep, from 

 paralysis of the orbicularis muscle. In cases of long stand- 

 ing, the globe of the eye may become inflamed from con- 

 stant exposure, from abolition of the movements of winking 

 by which the tears are distributed over its surface and little 

 foreign particles are removed, and, in short, from absence 

 of the protective action of the lids. In these cases, the lower 

 lid may become slightly everted. The frontal portion of the 

 occipito-frontalis, the attrahens aurem, and the corrugator 

 supercilii muscles, are also paralyzed. The most prominent 



