946 



THE NERVOUS SYSTEM 



buccinator, incisivi, orbicularis oris, triangularis, quadratus labii inferioris, and the muscles 

 of the nose (fig. 740). 



The marginal mandibular (supra-mandibular) branch, passing downward and forward under 

 cover of the risorius and the depressors of the lower hp, commimicates with the buccal branches 

 and with the ramus colli of the facial nerve, and with the mental branch of the mandibular nerve. 

 It suppUes the quadratus labii inferioris and mentalis. 



The ramus colli (infra -mandibular branch) runs downward and forward under cover of 

 the platysma, which muscle it innervates (fig. 740). Beneath the platysma it forms one or 

 more communicating loops, near its commencement, with the great auricular nerve, and longer 

 loops, lower down, with the superficial cervical nerve. 



Central connections. — The nucleus of origin of the facial in the rhombencephalon includes 

 an anterior and a posterior group of cells which give rise respectively to its upper and lower ter- 

 minal divisions. They are associated with the somaesthetic area (lower third of the anterior 

 central gjTUs) by way of the pjTamidal fasciculi of the opposite and same sides, and with the 

 nuclei of the other cranial nerves, including the nucleus of termination of the glosso-palatine, by 

 wa}' of the reticular formation and the medial longitudinal fasciculus. 



Fig. 740. — Superficial_Distribution of the Facial and other Nerves of the Head. 



(After Hirschfield and Leveille.) 



Supra-orbital 

 Palpebral twig of ( 



lacrimal 

 Infratrochlear 



Temporal branch ,^^^ 

 of facial """" 



Zygomatic br. 



of facial 

 Maxillary div. 

 of trigeminus 



Infra-orbital 

 br. of facial 



Buccal branch of 

 facial 



Mental branch of 

 mandibular 



Supra-mandibular br of 

 facial 



Infra-mandibular branch (ramus 

 colli) of facial 



'■ Posterior auricular 



Auriculo- temporal 



Great occipital 

 Facial 



Lesser occipital 

 Great auricular 



Cervical cutaneous 



GLOSSO-PALATINE NERVE 



The glosso-palatine nerve {.sensory root or pars intermedia of facial, nerve of 

 Wrisberg) contains l)otli sensory and motor fibres. While it has a separate 

 attachment to tlie niedulhi, it courses in close company with the facial and, in 

 the internal auditory meatus, it is involved in the same sheath with the facial, 

 which relation is maintained by its larger part thence through the facial canal till 

 a short distance above; the stylo-mastoid foramen. Here this larger part leaves 

 the trunk of the facial as the vliorda iympani nerve. The origin, central connec- 

 tions and iK'rij)hcral distribution of the glosso-palatine are similar to those of the 



