ey 
JUGULAR VEINS 685 
responding artery. Its radicles come from the posterior part of the temporalis 
muscle and from the external ear. It receives the dorsal cerebral vein (V. cere- 
bralis dorsalis), which is the emissary of the transverse sinus of the dura mater, and 
emerges from the temporal canal behind the postglenoid process. The trans- 
verse facial vein (V. transversa faciei) runs at first above the artery of like name, 
then plunges deeply into the masseter and unites in front with the facial vein. It 
is connected with the vena reflexa and with the posterior deep temporal vein by a 
branch which emerges from the temporal fossa through the mandibular notch. 
3. The masseteric vein (V. masseterica) joins the jugular at the upper border 
of the sterno-cephalicus tendon. It is a short but large trunk which is formed 
by the confluence at the posterior border of the jaw of masseteric and pterygoid 
veins. The former is commonly connected by an anastomotic branch with the 
buccinator vein. 
4. The great auricular vein (V. auricularis magna) is a satellite of the posterior 
auricular artery above, but joins the jugular a variable distance below and behind 
the point of origin of the artery. 
5. The occipital vein (V. occipitalis) arises in the fossa atlantis by the union of 
two radicles. It passes downward and backward on the rectus capitis ventralis 
major and joins the jugular vein a variable distance in front of the termination of the 
external maxillary vein. The anterior radicle is the ventral cerebral vein (V. 
cerebralis ventralis). This is an emissary of the cavernous sinus of the dura mater; 
it emerges through the foramen lacerum posterius and is connected with a venous 
plexus in the infratemporal fossa. It receives the condyloid vein (V. condyloidea), 
which is an emissary of the basilar plexus and the petrosal sinus, and emerges 
through the hypoglossal foramen.t The posterior radicle is formed by the con- 
fluence of muscular and cerebro-spinal branches. The former (Ramus muscularis) 
comes through the foramen transversarium of the atlas from the muscles of the 
poll; it anastomoses with the vertebral and deep cervical veins. The latter (Ramus 
cerebrospinalis) receives emissary veins from the meningeal plexus in the atlas, 
which emerge through the intervertebral and alar foramina and the foramen of the 
lateral mass of the atlas. 
6. The external maxillary vein (V. maxillaris externa) arises by radicles which 
correspond in general to the branches of the artery of like name. It passes down 
over the cheek along the anterior border of the masseter muscle behind the artery, 
crossing over the parotid duct, which lies behind the vein lower down. Thus on 
the ramus and as they turn around its ventral border the artery is in front, the vein 
in the middle, and the duct posterior. In the mandibular space the vein is ventral 
to the artery for some distance, then parts company with the artery, runs straight 
backward along the ventral border of the parotid gland, and opens into the jugular 
vein at the posterior angle of the gland.2 The chief differences in the tributaries 
of the vein as compared with the branches of the corresponding artery are as follows: 
The labial veins (Vv. labiales), superior and inferior, are in the substance of the 
orbicularis oris near the free edges of the lips. The upper one is the larger. They 
anastomose with the opposite veins. They drain into a venous plexus which is 
situated in the submucous tissue of the cheek and the buccinator muscle, and from 
this plexus two veins emerge. The upper one passes back and joins the buccinator 
vein. The lower one, the common labial vein (V. labialis communis), receives a 
submental vein from the chin and joins the external maxillary vein. 
Three veins connect with the external maxillary at the anterior border of the 
masseter. 
1 On account of the existence of this cranial affluent the term eranio-occipital has been pro- 
posed for the venous trunk. 
* The venous angle formed by this junction indicates the position of the thyroid gland. 
