THE CIRCULATORY OR VASCULAR SYSTEM 1 03 



the lower jaw, and divides into three portions the max- 

 illary, the pterygoid, and the sphenomaxillary ; these are 

 subdivided into the following branches (see Fig. 51) : 



Af axillary. Pterygoid. 



Tympanic. 



{Mylohyoid. 

 Incisor. Beep temporal : / Anterior - 



Mental. Pterygoid. l Inferior. 



Middle meningeal. Masseteric. 



Small meningeal. Buccal. 



Sphenoniaxillarv. 



Posterior dental. Sphenopalatine. Posterior palatine. 



Infra-orbital. Pterygopalatine. Vidian. 



The Internal Carotid Artery. This arises from 

 the common carotid, curves backward and outward, and 

 ascends upward by the side of the pharynx to the carotid 

 foramen in the petrous portion of the temporal bone. It 

 then passes inward along the carotid canal, where it pierces 

 the dura mater and divides into three terminal branches. 

 This artery makes many curves, which may be seen at the 

 cervical portion, at the base of the skull. It divides into 

 the anterior and middle cerebral arteries. The cervical 

 portion of the artery gives off no branches. Within the 

 skull the following branches are given off: 



Tympanic. Anterior cerebral. 



Arteriae receptaculi. Middle cerebral. 



Anterior meningeal. Posterior communicating. 



Ophthalmic. Anterior choroid. 



The tympanic is a small branch given off in the carotid 

 canal; it penetrates the tympanum and unites with the 

 tympanic branch of the internal maxillary and the stylo- 

 mastoid arteries. 



The arteriae receptaculi are small vessels that supply the 



