40 DISSECTION OF THE FACE. 



contracted so as to prevent bulging of the cheek ; but in the use of a 

 blow-pipe it is distended over the volume of air contained in the mouth, 

 and drives out a continuous stream of air by its contraction. 



The VESSELS OF THE FACE (fig. 17) uro the facial and transverse facial 

 arteries with their accompanying veins. The arteries are branches of the 

 external carotid; and the facial vein is received into the internal jugular 

 trunk. 



The facial artery (fig. 17,/), a branch of the carotid, emerges from 

 the neck, and appears on the lower jaw anterior to the masseter muscle. 

 From this point the artery ascends in a tortuous manner, near the angle 

 of the mouth and the side of the nose, to the inner angle of the orbit, 

 where it anastomoses with the ophthalmic artery. The course of the ves- 

 sel is comparatively superficial in the mass of i'at of the inner part of the 

 cheek. At first it is concealed by the platysma whilst crossing the jaw, 

 but this thin muscle does not prevent pulsation being recognized during 

 life; and near the mouth the large zygomatic muscle is superficial to it. 

 The vessel rests successively on the lower jaw, buccinator muscle, ele- 

 vator of the angle of the mouth, and elevator of the upper lip. Accom- 

 panying the artery is the facial vein, which is nearly a straight tube, and 

 lies to the outer side. 



Branches. From the outer side of the vessel unnamed branches are 

 furnished to the muscles and integuments, some of which anastomose with 

 the transverse facial artery. From the inner side are given the following 

 branches : 



The inferior labial branch () runs inwards beneath the depressor 

 anguli oris muscle, and is distributed between the lower lip and chin; it 

 communicates with the inferior coronary, and with the labial branch of 

 the inferior dental artery. 



Coronary branches (r and s). There is one for each lip (superior and 

 inferior), which arise together or separately from the facial, and are di- 

 rected inwards between the orbicular muscle and the mucous membrane 

 of the lip, till they inosculate with the corresponding branches of the 

 opposite side. From the arterial arches thus formed, offsets are supplied 

 to the lips and labial glands. From the arch in the upper lip a branch is 

 given to each side of the septum of the nose, artery of the septum. 



The lateral nasal branch (p) arises opposite the ala nasi, and passes 

 beneath the levator labii superioris alseque nasi to the side of the nose, 

 where it anastomoses with the internal nasal branch of the ophthalmic 

 artery. 



The angular branch (o) is the terminal twig of the facial artery at the 

 inner angle of the orbit, and joins with a branch (external nasal) of the 

 ophthalmic artery. 



The facial vein commences at the root of the nose in a small vein 

 named angular (p. 21). It then crosses over the elevator of the upper lip, 

 and separating from the artery, courses beneath the large zygomatic mus- 

 cle to the side of the jaw. Afterwards it has a short course in the neck 

 to join the internal jugular vein. 



Branches. At the inner side of the orbit it receives veins from the lower 

 eyelid (inferior palpebral), and from the side of the nose. Below the 

 orbit it is joined by the infra-orbital vein, also by a large branch, anterior 

 internal maxillary, that comes from the pterygoid region; and thence to 

 its termination by veins corresponding with the branches of the artery in 

 the face and neck. 



