252 LABORATORY MANUAL FOR VERTEBRATE ANATOMY 



In the axilla the axillary vein receives the following branches: the hi 

 thoracic vein, the subscapular vein, and the cephalic vein. The long thorac 

 vein runs caudad on the thoracic wall in the serratus muscle; it then passes 

 the inner surface of the skin and extends the entire length of the abdominal wa 

 being especially prominent in females, where as the external mammary it collec 

 from the mammary glands. (The greater part of this vein was probably remov< 

 with the skin.) The subscapular vein enters the axillary dorsal to the precedin 

 It collects a conspicuous branch {thoracodorsal vein) from the latissimus dorsi ar 

 cutaneous maximus muscles; it then passes through the teres major muscle 

 the external surface of the shoulder where it collects from various muscles. Tl 

 cephalic 1 vein is the chief superficial vein of the arm. It can best be picked i 

 on the outer surface of the upper arm; near the distal end of the upper arm 

 penetrates deep between muscles and passing between the teres maj<3r and su' 

 scapularis muscles emerges on the internal surface of the shoulder and enters tl 

 axillary vein at the same place as or in common with the subscapular vei 

 Immediately beyond the entrance of these tributaries, the axillary vein becom 

 the brachial vein of the arm. This proceeds along the inner surface of the upp< 

 arm in company with an artery and a nerve. 



Return to the precaval vein. At the point of entrance of the subclavk 

 vein the precaval vein receives from the neck the external and internal juguh 

 veins. The external jugular vein is the large vein which extends forward 

 the depressor conchae posterior muscle (most superficial muscle of the ventr 

 surface of the neck). It appears as the anterior portion of the precaval. Tl 

 internal jugular vein is a very small vein which runs alongside the trachea, pas 

 ing the thyroid gland, and accompanying the carotid artery and the vagus nerv 

 The place of entrance of the internal jugular as well as its general relations a 

 highly variable; it may enter the precaval after the latter has received the sul 

 clavian, but it usually enters with the external jugular. The precaval vein mi 

 thus be said to be formed by the union of the subclavian, external jugular, ar 

 internal jugular veins. Follow the external jugular. Shortly anterior to i 

 union with the subclavian it receives the transverse scapular vein from the ventr 

 end of the shoulder and near the same level has a cross-connection (transver 

 jugular vein) with its fellow of the opposite side (this union was probab 

 destroyed in the previous dissection). Along the neck it receives various sm; 

 tributaries from muscles and about one inch posterior to the angle of the jaws 

 seen to be formed by the union of two veins, the anterior and posterior facial veir 

 The anterior facial vein proceeds to the angle of the jaws where it is seen to 1 

 formed by the union of veins from the anterior part of the face and jaws. Its ma 

 tributaries are the angular vein, which passes over the ventral part of the masset 

 muscle and then turns to the region in front of the eye, and the deep facial ve 

 which emerges between the masseter and digastric muscles and passes along t 



1 So named because the corresponding vein in man was formerly thought to connect with the he; 



