596 THE VASCULAR SYSTEMS 



Relations. In the neck its origin is superficial, being covered by the integument, Platysma, 

 and fascia; it then passes beneath the Digastric and Stylohyoid muscles and part of the sub- 

 maxillary gland. It lies upon the Middle constrictor of the pharynx, and is separated from 

 the Styloglossus and Hyoglossus muscles by a portion of the submaxillary gland. On the face, 

 where it passes over the body of the mandible, it is comparatively superficial, lying immediately 

 beneath the Platysma. In this situation its pulsation may be distinctly felt, and compression 

 of the vessel against the bone can be effectually made. In its course over the face it is covered 

 by the integument, the fat of the cheek, and, near the angle of the mouth, by the Platysma, 

 Risorius, and Zygomatic muscles. It rests on the Buccinator, the Levator anguli.oris, and the 

 Levator labii superioris (sometimes piercing or else passing under this last muscle). The 

 facial vein lies to the outer side of the artery, and takes a more direct course across the face, 

 where it is separated from the artery by a considerable interval. In the neck it lies superficial 

 to the artery. The branches of the facial nerve cross the artery, and branches of the infra- 

 orbital nerve lie beneath it. 



Branches. The branches of this vessel may be divided into two sets those 

 given off below the mandible (cervical), and those on the face (facial). 



Cervical Branches. Facial Branches. 



Ascending Palatine. Inferior labial. 



Tonsillar. Inferior labial coronary. 



Submaxillary. Superior labial coronary. 



Submental. Lateral nasal. 



Angular. 



Muscular. 



The ascending palatine (a. palatine ascendens) passes up between the Styloglossus 

 and Stylopharyngeus to the/outer side of the pharynx, along which it is continued 

 between the Superior constrictor and the Internal pterygoid to near the base of 

 the skull. It divides, near the Levator palati, into two branches; one follows 

 the course of the Levator palati, and, winding over the upper border of the Superior 

 constrictor, supplies the soft palate and the palatine glands, anastomosing with its 

 fellow of the opposite side and with the posterior palatine branch of the internal 

 maxillary artery; the other pierces the Superior constrictor and supplies the tonsiL 

 and Eustachian tube, anastomosing with the tonsillar and ascending pharyngeal 

 arteries. 



The tonsillar branch (ramus tonsillaris) passes up between the Internal pterygoid 

 and Styloglossus, and then ascends along the side of the pharynx, perforating the. 

 Superior constrictor, to ramify in the substance of the tonsil and root of the tongue. 



The submaxillary or glandular branches (rami glandulares) consist of three or 

 four large vessels, which supply the submaxillary gland, some being prolonged to 

 the neighboring muscles, lymph nodes, and integument. 



The submental (a. submentalis) (Fig. 438), the largest of the cervical branches. 

 is given off from the facial artery just as that vessel emerges from the submaxillary 

 gland; it runs forward upon the Mylohyoid muscle, just below the body of the 

 mandible and beneath the Digastric; after supplying the surrounding muscles, 

 and anastomosing with the sublingual artery by branches which perforate the 

 Mylohyoid muscle, it arrives at the symphysis of the mandible, where Jt_tlirns 

 over the border of the mandible and divides into a superficial and a deep branch; 

 the former passes between the integument and Depressor labii inferioris, supplies 

 both, and anastomoses with the inferior labial. The deep branch passes between 

 the latter muscle and the bone, supplies the" lip, and anastomoses with the inferior 

 labial and mental arteries. 



The inferior labial (a. labialis inferior) (Fig. 441) passes beneath the Depressor 

 anguli oris, to supply the muscles and integument of the chin and lower lip, anasto- 

 mosing with the inferior labial coronary and submental branches of the facial, and 

 with the mental branch of the inferior dental artery. 



