210 The Alligator and Its Allies 
three short branches, with the external jugular, 
ej, to be described later. Its distribution in 
the cranial cavity could not be determined in the 
available material. At the point of entry of the 
internal jugular the precava passes laterad for a 
short distance and then divides into two more or 
less equal branches, the above-mentioned external 
jugular, ej, and the subclavian, s, of which the 
latter will first be described. 
The subclavian, s, of course, returns blood from 
the regions of the shoulder and arm. On reaching 
the body wall, where it might be called the axzllary, 
ax, it receives, on its posterior side, a large thoracic 
vein, t, which returns blood from the thorax, 
shoulder, and skin. The thoracic receives a 
branch from the posterior surface of the arm, 
which might be called the postbrachial, pb; this 
postbrachial may be traced, as a rather small 
vessel, to the hand; at the elbow it is connected, 
by one or more small branches, with the brachial. 
Just distal to the thoracic the axillary vein 
receives two fairly large vessels, the subscapulars, 
sc, that return blood from the shoulder and 
upper arm. After receiving the subscapulars, 
the axillary may be followed into the upper 
arm as the brachial, br. As has been said, the 
brachial and postbrachial anastomose near the 
elbow, and in this region the former receives a 
small vessel that extends parallel to it from the 
manus. 
