ST6 ARTERIES. 



mouth ; it passes upwards and inwards beneath the Depressor anguli oris, and, 

 penetrating the Orbicularis 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 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, 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 artery of 

 the septum, ramifies on the septum of the nares as far as the point of the nose ; 

 another 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 artery of the septum, 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, accompanied by a large vein, the angular ; it dis- 

 tributes some branches on the cheek which anastomose with the infra- orbital, and, 

 after supplying the lachrymal sac, and Orbicularis muscle, terminates by anas- 

 tomosing 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 with other vessels from different sources ; viz., with 

 the sublingual branch of the lingual, with the mental branch of the inferior dental 

 as it emerges from the dental foramen, with the ascending pharyngeal and pos- 

 terior palatine, and with the ophthalmic, a branch of the internal carotid ; it also 

 inosculates with the transverse facial, and with the infra-orbital. 



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

 This vessel also is 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 cases of hemorrhage from the lips, 

 the result either of an accidental wound, or from an operation; but its application is useless, on 

 account of the free communication of this vessel with its fellow, and with numerous branches 

 from different sources. In a wound involving 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 a tenaculum. In 

 order to prevent hemorrhage in cases of excision, or in the removal of diseased growths from the 

 part, the lip should be compressed on each side between the finger and thumb, whilst the surgeon 

 excises the diseased part. In order to stop hemorrhage 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 adapted to each other, but the possibility of hemorrhage is prevented by including in the 

 suture the divided artery. If the suture is. on' the contrary, passed through merely the cutane- 

 ous portion of the wound, hemorrhage 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 operat- 

 ing for fistula lacrymalis, the sac should always be opened on its outer side, in order that ^his 

 vessel may be avoided. 



The OCCIPITAL AETEEY 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, and 

 part of the parotid gland, the hypoglossal nerve winding around it from behind 

 forwards ; higher up, it passes across the internal carotid artery, the internal jugular 

 vein, and the pneumogastric and spinal accessory nerves; it then ascends to the 

 interval between the transverse process of the atlas and the mastoid process of the 

 temporal bone, passes horizontally backwards, grooving the surface of the latter bone, 



