324 THE CIRCULATORY SYSTEM. 
maxillary gland (11) to join the anterior facial (c) caudad of the 
angle of the jaw. 
As it passes ventrad of the parotid gland (10), just before 
becoming superficial, the posterior facial receives the super- 
ficial temporal (7). This at first follows the superficial tem- 
poral artery (s), then enters the substance of the parotid gland, 
joining the posterior facial near the ventral border of the latter. 
The superficial temporal receives the anterior auricular (v), a 
large vein passing along the cranial border of the auricular 
opening and arising dorsad of the eye. 
The posterior facial receives also, at the point where it 
passes from beneath the parotid gland, the posterior auricular 
or great auricular vein (7). This collects blood from the back 
of the head and the external ear, its branches following those 
of the artery of the same name. It passes along the caudal 
border of the parotid gland to join the posterior facial. 
VEINS OF THE BRAIN AND SPINAL CORD,—The veins of 
the brain form a large number of small vessels which pour their 
blood into larger veins lying in folds of the dura mater; these 
are known as the venous sinuses of the dura mater. These 
sinuses communicate with the venous plexus about the orbital 
fissure, coming from the posterior facial vein; with the internal 
jugular through the jugular foramen, and with the vertebral 
veins, in the vertebral canal. The chief sinuses of the dura 
mater on the dorsal side of the brain are as follows: 
1. Sinus sagittalis superior.—This lies in the dorsal part 
of the falx cerebri, between the two hemispheres of the cere- 
brum. It receives veins from the darsal and middle parts of 
the cerebrum, and passes caudad to the tentorium. Here it 
enters the sinus transversus. It receives the vena cerebri 
magna, a large vein coming from the interior of the brain and 
passing directly dorsad at the caudal end of the corpus callosum 
to enter the sinus sagittalis. 
2. Sinus transversus.—This lies in a canal in the dorsal 
border of the tentorium. It receives numerous small veins 
from the cerebellum, roof of the skull, etc. One or two centi- 
meters on each side of the middle line the sinus transversus 
passes out of the canal onto the caudal surface of the tentorium, 
