NERVES OF THE FACE. 301 



liably lies between the parotid and submaxillary and separates 

 the latter from the lymphatic immediately cephalad of it. Zygoma, 

 arcus zygomaticus. — The zygomatic arch (Fig. 56). 

 For the manner of preparation, see §§ 772, 777. 



§ 778. Nerves. — Oermco-facial division of the facialis (vii) 

 (Fig. 87). — This emerges from the ental surface of the lymphatic 

 gland (Fig. 87, Gl. lym.), crosses the V. facialis and divides into the 

 two main divisions, one of which extends along the mandible, the 

 other dorso-cephalad toward the angle of the mouth. 



Temporo facial division of the facialis (vii) (Fig 87, N. tmp. 

 fac). — About 1 cm. dorsad of the parotid duct there emerges an- 

 other branch which extends dorso-cephalad and spreads out in 

 many branches over the side of the head and face. 



Temporo-auricular division of the trigeminus (branch of the 3d 

 or inferior division of the V" nerve). — It has the same general direc- 

 tion as the temporo-facial branch of the facialis and anastomoses 

 freely with it. Its fine branches spread out over the head and face 

 as do those of the temporo-facial. 



At the dorso-cephalic angle of the parotid emerges another 

 branch of the temporo-auricular (Fig. 87, N. tmp. aur.). It extends 

 almost directly dorsad. 



Auricularis magnus (Fig. 87). — This large spinal nerve emerges 

 from between the MM. clavo-trapezius and sterno-mastoideus. It 

 then extends dorso-cephalad and spreads out over the caudal sur- 

 face of the external ear. 



GLANDULE SALIVARI^. 



§ 779. Glandiila parotis— Parotid gland. — The position and 

 relations of this gland are well shown in Fig. 87. It surrounds the 

 ventral half of the external ear. 



§ 780. Ductus Stenonianus — Stenon's duct, duct of the parotid 

 gland (Fig. 87). — It extends cephalad from the cephalic edge of the 

 gland along the ectal surface of the masseter muscle, nearly directly 

 toward the angle of the mouth. When near the edge of the lip it 

 penetrates the cheek, passing entad of the facial vein (Fig. 87, V. 

 facialis). It opens on the mucous surface of the cheek opposite the 

 most prominent cusp of the last prsemolar (Fig. 57). 



Isolate the duct as directed for nerves and vessels (§ 777). It 

 may be easily traced if it has been injected or if a black bristle has 



