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The Cephalic Veins and Sinuses of Reptiles 
on the lateral side of the lachrymal duct. Above the front of the bulbus 
the vein again communicates with the sinus orbitalis, then bends caudad 
over the bulbus to join the vena palpebralis inferior as stated above. The 
vena palpebralis and its tributaries are considerably enlarged and form 
practically a portion of the sinus orbitalis. 
A venous ring, surrounding the outer part of the bulbus, was observed 
by Grosser and Brezina, 95, who derive it from their vena orbitalis 
superior. Since, however, the ring is not continuous in the adult animal, 
it has seemed best to reject the name vena orbitalis superior, and to 
employ the terms used in the description of the palpebral veins of the 
lizard, to which the veins of the snake correspond, at least in a topo- 
graphical sense. 
b. VENA CEREBRALIS MEDIA. 
The primitive relations of the intracranial veins, together with certain 
changes which occur during late embryonic stages, have been mentioned 
above. In the case of the vena cerebralis anterior and vena cerebralis 
posterior I have nothing to add to the account of Grosser and Brezina. 
The vena cerebralis media, on the other hand, has three anastomoses in 
the adult snake which are not described by these authors. 
(1) In an anterior direction the vena cerebralis media shows, in addi- 
tion to the internal “ secundire Verbindung ” (c. 7., Text Fig. 4), another, 
external anastomosis with the vena cerebralis anterior. The new vein 
(c. e., Text Fig. 4) begins as an extracranial vessel at the sinus prooticus, 
from which it runs downward and forward and enters the cranium be- 
tween the prootic and basisphenoid bones. It joins the vena cerebralis 
anterior on the lateral aspect of the ramus ophthalmicus V and imme- 
diately below the junction of the internal anastomosis with that vein. 
At the junction of these three veins a vena hypophyseos (v. hy.) also 
forms a connection with the vena cerebralis anterior. 
(2) Vena Palato-cerebralis (v. p. c., Text Fig. 4) —This vein joins 
the vena cerebralis media secunda just outside of the foramen for the 
maxillaris and mandibularis nerves. It places the vena cerebralis media 
in communication with the system of palatine veins which is described 
below. ‘Through the vena palato-cerebralis the vena cerebralis media 
acquires also indirect connection with the vena maxillaris. 
(3) Vena Capitis Dorsalis (v. ¢. d., Text Fig. 4).—This sinus-lke 
vein springs from the dorsal portion of the vena cerebralis media, near 
the junction of the latter with the vena longitudinalis cerebri. It runs 
dorsad from its origin and escapes from the cranium by a special fora- 
