THE ARTERIES. 287 
d. A. auricularis posterior (Fig. 119, 0).—The posterior 
auricular leaves the external carotid (#) opposite the middle of 
the bulla tympani and beneath the submaxillary gland. It 
passes about the base of the ear on ‘its caudal and dorsal sides 
outside of the deep muscles of the occipital region, but beneath 
the auricular muscles, and sends several branches to the muscles 
of the external ear, passing onto the caudal surface of the 
concha. It sends also a large branch mediad to the muscles 
of the occiput, especially to the temporal muscle, within which 
it ramifies. A large branch (anterior auricular, Fig. 131, 7) 
passes from the caudal side of the concha craniodorsad, and 
appears on the cranial side of the external ear, running along 
the cranial margin of the auditory opening. 
e. A. temporalis superficialis (Fig. 119, 9; Fig. 120, 4). 
—The superficial temporal artery arises from the external 
carotid as the latter lies between the cartilaginous auditory 
meatus and the caudal border of the masseter muscle. It 
passes dorsad and gives off soon after its origin a muscular 
branch to the masseter, and an auricular branch which passes 
distad along the concha auris and ramifies over its cranial 
surface. The superficial temporal itself passes onto the surface 
of the temporal muscle (Fig. 120, 11), to which it gives 
numerous branches. It extends to the caudal angle of the eye 
(Fig. 131, s), where it divides. One branch passes into the 
lower eyelid; the larger branch passes along the dorsal side of 
the eye, sending a branch into the orbit and small branches 
onto the dorsal surface of the nose. 
Jy. A. maxillaris interna (Fig. 119, ~; Fig. 120, ¢7).—The 
internal maxillary artery is the continuation of the external 
carotid. It turns caudad at the caudal end of the mandible, 
then passes craniad, lying dorsad of the pterygoid muscles 
(Fig. 120, 10), and against the medial surface of the mandible. 
It gives off the inferior alveolar artery (Fig. 120, 7), then the 
middle meningeal (#), and then continuing mediad divides into 
three or four branches. The branches redivide, and the twigs 
form a complicated plexus, the carotid plexus (Fig. 120, /), 
which surrounds the maxillary division of the fifth nerve near 
its exit from the foramen rotundum. One of the larger 
