30 Arteries of Head and Neck 



a tonsillar branch, which, mounting by the internal pterygoid muscle 

 send twigs through the superior constrictor to the tonsil. The sub- 

 maxillary branches of the facial supply the salivary gland, and the 

 submental runs forward on the mylo-hyoid and supplies the chin and 

 the lip, anastomosing with its fellow. 



Above the jaw the branches are : inferior labial and inferior 

 coronary, the latter lying between the mucous membrane and the 

 orbicularis, as does also the superior coronary. These three branches 

 anastomose with their fellows across the middle line, and the superior 

 coronary gives a branch to the septum of the nose. The lateral nasal 

 branches also anastomose with their fellows of the opposite side over 

 the ridge of the nose, and the angular, as already mentioned, joins 

 the nasal of the ophthalmic. The angular artery is upon the nasal side 

 of the lachrymal sac. The facial may be readily compressed or tied 

 as it passes over the lower jaw. 



The occipital artery is a posterior branch of the external carotid 

 in the superior carotid triangle, out of which it passes under the 

 guidance of the digastric and stylo-hyoid to the interval bet -.veen the 

 transverse process of the atlas and the mastoid process. As the ex- 

 ternal carotid is anterior to the internal carotid, the occipital branch 

 has to cross the internal carotid and jugular vein. The hypoglossal 

 nerve hooks round the occipital artery. Arrived at the bony inter- 

 space just alluded to, the occipital artery necessarily lies under cover 

 of the sterno-mastoid, splenius capitis, and trachelo-mastoid, in addi- 

 tion to the origin of the digastric. It grooves the temporal* bone, and 

 then lies on the superior oblique and complexus, and ultimately pierces 

 the cranial origin of the trapezius. It ramifies in the scalp as high 

 as the vertex, anastomosing with its fellow and with the posterior 

 auricular and the superficial temporal arteries. At the back of the 

 head it is accompanied by the great occipital nerve. As it mounts 

 towards the vertex it crosses the middle of a line between the occipital 

 protuberance and the external auditory meatus, at which spot it can 

 readily be compressed. 



Branches. The occipital artery gives off muscular twigs ; an 

 auricular branch to the concha ; meningeal twigs through the posterior 

 lacerated foramen ; voAHtot princcps cervicis, which descends between 

 the complexus and semi-spinaliscolli to anastomose with the vertebral 

 and with the profunda cervicis of the superior intercostal arteiy. A 

 more superficial branch of the princeps runs beneath the border of the 

 trapezius, to communicate with the superficial branch of the transverse 

 cervical. 



The posterior auricular springs from the carotid above tin- 

 crossing of the digastric, and, therefore, is not in the superior carotid 

 triangle. It is crossed by the portio dura, and mounts under cover 

 of the parotid gland to the crevice between the mastoid process and 

 the concha, giving twigs to the scalp and to the pinna, which anasto- 



cle, 

 ub- 



