Henry L. Bruner 33 
men, which lies between the anterior semi-circular canal and the utric- 
ulus. Outside of the skull the vein receives a small cutaneous tributary 
(v. c., Text Fig. 4), then runs directly caudad between the prootic and 
squamosal bones. Here the vein receives a second cutaneous tributary, 
then bends directly laterad, under the posterior end of the squamosal 
bone, and joins the vena jugularis interna. 
Through the vena capitis dorsalis. indirect connection is established 
between the vena cerebralis media and the vena jugularis interna. The 
connecting vein probably forms an important outlet for the escape of 
blood from the cranial cavity. 
The anterior part of the vena capitis dorsalis probably includes the 
vena cutanea which Grosser and Brezina describe as entering the vena 
cerebralis media from the top of the head. 
ec. VENA MANDIBULARIS. 
(v. m., Text Figs. 1 and 4.) 
The vena mandibularis, as here described, includes the vena maxillaris 
and vena maxillaris inferior of Grosser and Brezina, whose vena maxil- 
laris superior is called vena maxillaris in this paper. A similar termi- 
nology has been generally accepted for the nerves and skeletal parts and 
is evidently to be preferred also for the veins under consideration. 
The vena mandibularis begins in a median sinus which les behind the 
ligament connecting the anterior ends of the lower jaw. From the sinus 
the vein runs caudad between the mandible on one hand and the tongue, 
larynx, and trachea on the other; it joins the vena jugularis interna under 
the posterior end of the mandible. At the junction of the two veins a 
striated constrictor muscle (m. constrictor vene jugularis interna) sur- 
rounds both the jugular vein and the terminal portion of the vena 
mandibularis. 
Both venz mandibulares are considerably enlarged, the right vein 
(v. m. d., Text Fig. 4) more than the left (v. m. s.). Where it joins 
the vena jugularis interna the right vena mandibularis has about twice 
the diameter of the vena jugularis itself. On the left side the vena 
mandibularis and vena jugularis interna are about equal at their junction. 
The chief tributary of the vena mandibularis is the vena mavxillaris. 
VENA MAXILLARIS (v. ma., Text Figs. 1 and 4).—On account of its 
great length and size the vena maxillaris is the most remarkable vein 
of the dorsal head region of the snake. The anterior part of the vein 
is much enlarged and resembles a sinus more than a vein. Near the 
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