38 TOPOGRAPHICAL ANATOMY OF THE 



the naso-labial muscle, and ou the surface of the levator labii superioris 

 proprius, by dividing into the dorsal nasal artery and the angular 

 artery of the eye. In its course across the face the artery lies in 

 succession upon (that is, lateral to) the depressor labii inferioris, 

 buccinator, and levator labii superioris proprius muscles. It also 

 crosses, very obliquely, the parotid duct which insinuates itself 

 between the buccinator muscle and the facial vessels. Crossing the 

 lateral aspect of the artery are the buccal nerves and the zygomatic 

 muscle. 



The following are the branches of the facial artery : — 



(1) Rami musciolares to the masseter and cutaneous muscles. 



(2) Rami cutanei to the skin of the face. 



(3) A. lahialis inferior. — The inferior labial artery takes origin 

 at the lower border of the buccinator muscle. It runs forwards into 

 the lower lip under cover of the risorius, buccinator, and depressor 

 labii inferioris muscles, and can be traced to a union with the cor- 

 responding artery of the other side of the head. A small angular 

 artery of the mouth (a. angularis oris) arises from the inferior labial 

 as this vessel reaches the border of the orbicularis muscle, and anasto- 

 moses with twigs from the superior labial artery. 



(4) A. lahialis superior. — The superior labial artery arises at the 

 end of the facial crest. For a distance it follows the lower border 

 of the caninus muscle, and then continues on the deep face of this 

 muscle into the upper lip. Here its terminal branches anastomose 

 with similar branches of the artery of the opposite side of the head, 

 and with terminal branches of the major palatine artery. 



(5) A. ktteralis nasi. — The lateral nasal artery, as a rule, leaves 

 the facial just before the border of the levator labii superioris proprius 

 is reached, and passes to the side of the nose under the naso-labial 

 muscle. Branches of the lateral nasal and superior labial arteries 

 anastomose, and usually there is an anastomosis between the lateral 

 nasal and the infra-orbital arteries. 



Not infrequently the lateral nasal artery is double. 



(6) A. dorsalis nasi. — The dorsal nasal artery passes under the 

 naso-labial muscle to the dorsum of the nose. It helps to supply 

 the wall of the diverticulum of the nostril. 



(7) A. o/iigularis oculi. — The angular artery of the eye continues 

 the upward curve of the facial and reaches the medial angle of the 

 eye. It very commonly anastomoses with the malar branch of the 

 infra-orbital artery. 



V. FACIALIS. — The facial vein follows the posterior border of the like- 

 named artery, and receives tributaries corresponding to the branches 



