738 HUMAN ANATOMY. 



through the submaxillary gland. It passes forward upon the mylo-hyoid muscle, close to its 

 origin, until it reaches the insertion of the anterior belly of the digastric, when it passes upward 

 upon the ramus of the mandible to supply the depressor labii inferioris and to anastomose with 

 the mental branches of the inferior dental artery and with the inferior labial branches of the 

 facial. It sends branches to the muscles in its vicinity and also to the integument, and branches 

 perforate the mylo-hyoid muscle to anastomose with the sublingual branches of the lingual. 



From the facial portion, (e) The masseteric branches arise from the posterior surface of 

 the artery — and are directed upward to supply the masseter muscle and to anastomose with 

 branches of the internal maxillary and transverse facial arteries. 



{/ ) The inferior labial branch (a. labialis inferior) passes forward along the outer surface 

 of the horizontal ramus of the mandible, supplying the depressor anguli oris, the depressor 

 labii inferioris, and the integument, and anastomosing with the mental branches of the inferior 

 dental and submental arteries. 



{£■) The inferior coronary artery passes forward in the substance of the lower lip between 

 the mucous membrane and orbicularis oris, supplying the latter, and terminates by anastomosing 

 with its fellow of the opposite side. 



{/t) The superior coronary artery (a. labialis superior) has the same course and relations in 

 the upper lip that the inferior coronary has in the lower one. It anastomoses with its fellow of 

 the opposite side, and near its termination usually sends a small branch upward to the septum 

 of the nose, the a. septi narium. 



(?) The lateral nasal takes its origin just as the artery reaches the naso-labial angle ; it 

 passes forward over the ala of the nose, supplying its muscles and integument. 



(/ ) The angular artery (a. angularis) is the terminal portion of the facial artery beyond 

 the naso-labial angle. It passes directly upward in the angle between the nose and the cheek, 

 and gives branches to the adjacent muscles, the lachrymal sac, and the orbicularis palpebrarum, 

 anastomosing with the nasal branch of the ophthalmic artery and with the infra-orbital branch 

 of the internal maxillary. 



Anastomoses. — The facial artery, by means of its facial branches and the sub- 

 mental arteries, makes abundant anastomoses with its fellow of the opposite side. 

 In addition, it is connected with other branches of the external carotid; with the 

 dorsalis linguae and submental branches of the lingual by its tonsillar and inferior 

 labial branches respectively; with the descending palatine, infra-orbital branches, and 

 mental branches of the internal maxillary by its tonsillar, angular, and inferior labial 

 branches; and with the transverse facial branch of the superficial temporal by its 

 masseteric branches. Finally, it is connected with the ophthalmic branch of the 

 internal carotid by the angular artery. 



Variations. — The facial artery may arise by a trunk common to it and the lingual, or it 

 may arise above the level of the angle of the jaw. Quite frequently it does not extend upon the 

 face beyond the angle of the mouth, being replaced in the upper part of its course by branches 

 from the transverse facial or internal maxillary artery. 



The ascending palatine branch frequently arises directly from the external carotid, or it 

 may take its origin from the ascending pharyngeal or from the occipital, and the tonsillar is 

 frequently a branch of it. The submental branch may be greatly reduced in size or even 

 absent, being replaced in whole or in part by the sublingual, these two arteries being inversely 

 proportionate to each other so fai as their development is concerned. 



Practical Considerations. — The facial artery may require ligation on account 

 of division of one of its branches, as the coronary, but whenever direct ligation 

 of the wounded vessel is possible, it is preferable on account of the very free 

 anastomosis between the branches of opposite sides, leading usually, after ligation 

 of the main trunk, to recurrence of the hemorrhage. In bleeding after tonsillotomy 

 (page i6oS), either the tonsillar branch of the facial or the main vessel (where it runs 

 between the posterior belly of the digastric and the stylo-glossus muscles) may be 

 involved ; but as the blood may also be furnished by the ascending pharyngeal, 

 ligation of the external carotid itself rather than of the facial would be more likely to 

 be efficient. 



LiQ;ation. — {a) The cervical portion of the vessel may be reached through an 

 incision like that for the lingual, placed a litde higher, and not extending so far 

 anteriorly. When the submaxillary gland is drawn upward, the artery will be drawn 

 with it and made prominent. This portion may also be reached near its origin by 

 uncovering the external carotid {q.v.) and identifying the vessel where it runs 



