556 THE ARTERIES. 



muscles and integument of the lower lip, anastomosing with the inferior coronary 

 and submental branches of the facial, and with the mental branch of the inferior 

 dental artery. 



The inferior coronary is derived from the facial artery, near the angle of the 

 mouth : it passes upward and inward beneath the depressor anguli oris. and, pen- 

 etrating the Orbicularis oris muscle, runs in a tortuous course along the edge of 

 the lower lip between this muscle and the mucous membrane, inosculating with 

 the artery of the opposite side. This artery supplies the labial glands, the mucous 

 membrane, and muscles of the lower lip, and anastomoses with the inferior labial 

 and the mental branch of the inferior dental artery. 



The superior coronary is larger and more tortuous in its course than the pre- 

 ceding. It follows the same course along the edge of the upper lip, lying between 

 the mucous membrane and the Orbicularis oris, and anastomoses with the artery 

 of the opposite side. It supplies the textures of the upper lip, and gives off in its 

 course two or three vessels which ascend to the nose. One, named the inferior 

 artery of the septum, ramifies on the septum of the nares as far as the point of the 

 nose ; another, the artery of the ala, supplies the ala of the nose. 



The lateralis nasi is derived from the facial, as that vessel is ascending along 

 the side of the nose ; it supplies the ala and dorsum of the nose, anastomosing 

 with its fellow, the nasal branch of the ophthalmic, the inferior artery of the 

 septum, the artery of the ala, and the infra-orbital. 



The angular artery is the termination of the trunk of the facial ; it ascends to 

 the inner angle of the orbit, imbedded in the fibres of the Levator labii superioris 

 alaeque nasi, and accompanied by a large vein, the angular ; it distributes some 

 branches on the cheek which anastomose with the infra-orbital, and after supplying 

 the lachrymal sac and Orbicularis palpebrarum muscle, terminates by anastomos- 

 ing with the nasal branch of the ophthalmic artery. 



The anastomoses of the facial artery are very numerous, not only with the 

 vessel of the opposite side, but, in the neck, with the sublingual branch of the 

 lingual ; with the ascending pharyngeal ; with the posterior palatine, a branch of 

 the internal maxillary, by its inferior or ascending palatine and tonsillar branches ; 

 on the face, with the mental branch of the inferior dental as it emerges from the mental 

 foramen, with the transverse facial, a branch of the temporal ; with the infra-orbital, 

 a branch of the internal maxillary, and with the nasal branch of the ophthalmic. 



Peculiarities. The facial artery not unfrequently arises by a common trunk with the 

 lingual. This vessel is also subject to some variations in its size and in the extent to which it 

 supplies the face. It occasionally terminates as the submental, and not unfrequently supplies 

 the face only as high as the angle of the mouth or nose. The deficiency is then supplied by 

 enlargement of one of the neighboring arteries. 



Surgical Anatomy. The passage of the facial artery over the body of the jaw would 

 appear to afford a favorable position for the application of pressure in case of haemorrhage 

 from the lips, the result either of an accidental wound or during an operation ; but its applica- 

 tion is useless, except for a very short time, on account of the free communication of this 

 vessel with its fellow and with numerous branches from different sources. In a wound involv- 

 ing the lip it is better to seize the part between the fingers, and evert it, when the bleeding 

 vessel may be at once secured with pressure -forceps. In order to prevent haemorrhage in cases 

 of removal of diseased growths from the part, the lip should be compressed on each side 

 between the fingers and thumb or by a pair of specially devised clamp-forceps, whilst the surgeon 

 excises the diseased part. In order to stop haemorrhage where the lip has been divided in an 

 operation, it is necessary, in uniting the edges of the wound, to pass the sutures through the 

 cut edges, almost as deep as its mucous surface ; by these means not only are the cut surfaces 

 more neatly and securely adapted to each other, but the possibility of haemorrhage is prevented 

 by including in the suture the divided artery. If the suture is, on the contrary, passed through 

 merely the cutaneous portion of the wound, haemorrhage occurs into the cavity of the mouth. 

 The student should, lastly, observe the relation of the angular artery to the lachrymal sac. and 

 it will be seen that, as the vessel passes up along the inner margin of the orbit, it ascends on 

 its nasal side. In operating for fistula luchrymalis the sac should always be opened on its outer 

 side, in order that this vessel may be avoided. 



The Occipital Artery (Fig. 349) arises from the posterior part of the external 

 carotid, opposite the facial near the lower margin of the Digastric muscle. At its 

 origin it is covered by the posterior belly of the Digastric and Stylo-hyoid muscles, 



