286 THE CIRCULATORY SYSTEM. 



turns mediad, lying against the cartilaginous auditory meatus, 

 on its cranial side, and gives off the superficial temporal (/). 

 The artery then continues mediad, taking the name internal 

 maxillary (n} so that the internal maxillary artery is to be 

 considered the terminal branch of the external carotid. 

 Branches of the external carotid artery (Fig. 119): 



a. A. lingualis (Fig. 119, z; Fig. 120, d). The lingual 

 artery leaves the external carotid near its beginning and passes 

 craniomediad along the ventral border of the digastric muscle 

 (Fig. 1 20, 9), accompanied by the hypoglossal nerve. It gives 

 off numerous small branches to the hyoid and pharyngeal 

 muscles, then passes dorsad of the hyoglossus muscle (Fig. 

 1 2O, 6), where it gives off a branch which passes transversely 

 across the middle line to communicate with the artery of the 

 other side. Beneath the hyoglossus the artery turns craniad 

 and passes into the tongue. Here it runs along the medial 

 border of the styloglossus to the tip of the tongue, giving off 

 numerous branches into the substance of this organ. 



b. Rami musculares. Muscular branches pass to the 

 digastric and to the hyoid muscles. A small branch (Fig. 119, 

 /^), which may arise either from the external carotid or from 

 the common carotid near the beginning of the external carotid, 

 passes to the larynx and supplies the thyroarytenoid and lateral 

 cricoarytenoid muscles of the larynx. 



c. A. maxillaris externa (Fig. 119,7'). Tne external 

 maxillary artery leaves the external carotid (m) opposite the 

 angle of the jaw and at about the dorsal border of the digastric 

 muscle (s). It passes craniad, lying at first beneath the 

 digastric muscle and sending a branch to the submaxillary 

 gland. Opposite the caudal border of the mylohyoid muscle 

 it gives off the submental artery, turns dorsad, emerges from 

 beneath the digastric, and passes along the cranial border of the 

 masseter onto the face. Here it divides into superior (k) and 

 inferior (/) labial branches, which pass along the upper and 

 lower lips, respectively, giving off numerous branches. 



The submental artery passes to the symphysis menti 

 between the digastric and mylohyoid muscles, giving off on its 

 course collateral branches to the muscles of this region. 



