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TEXT-BOOK OF PHYSIOLOGY. 



muscles of the face. These muscles by their individual and cooperative 

 contraction express ideas and feelings and are therefore termed muscles of 

 expression. By reason of the association of the cortical facial area and the 

 nucleus of origin of the facial nerve the latter becomes the medium of 

 communication between the cortical area 'and the facial muscles and serves 

 for the transmission to the muscles of those nerve impulses developed by 



FIG. 277. SUPERFICIAL BRANCHES or THE FACIAL AND THE FIFTH. i. Trunk of the facial. 

 2. Posterior auricular nerve. 3. Branch which it receives from the cervical plexus. 4. Occipital 

 branch. 5, 6. Branches to the muscles of the ear. 7. Digastric branches. 8. Branch to the 

 stylo-hyoid muscle. 9. Superior terminal branch. 10. Temporal branches, n. Frontal 

 branches. 12. Branches to the orbicularis palpebrarum. 13. Nasal or suborbital branches. 

 14. Buccal branches. 15. Inferior terminal branch. 16. Mental branches. 17. Cervical 

 branches. 18. Superficial temporal nerve (branch of the fifth) . 19, 20. Frontal nerves (branches 

 of the fifth). 21, 22, 23, 24, 25, 26, 27. Branches of the fifth. 28, 29, 30, 31, 32. Branches of the 

 cervical nerves. (Hirschfeld.) 



and associated with psychic states. The muscles thus excited to action 

 individually and collectively express in a general way the character of 

 the psychic state. For this reason the facial nerve is termed the nerve of 

 expression. 



Branches of the Facial Nerve ; Their Origin, Properties and Func- 

 tions. Between the facial and the acoustic nerve there is a small nerve known 

 as the pars intermedia, the nervus intermedius or the nerve of Wrisberg. The 

 true nature of this nerve has long been a subject of investigation. The 



