252 LABORATORY MANUAL FOR VERTEBRATE ANATOMY 



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

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

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

 the inner surface of the skin and extends the entire length of the abdominal wall, 

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

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

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

 It collects a conspicuous branch (thoracodorsal vein) from the latissimus dorsi and 

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

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

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

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

 penetrates deep between muscles and passing between the teres major and sub- 

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

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

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

 the brachial vein of the arm. This proceeds along the inner surface of the upper 

 arm in company with an artery and a nerve. 



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

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

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

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

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

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

 ing the thyroid gland, and accompanying the carotid artery and the vagus nerve. 

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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



1 So named because the corresponding vein in man was formerly thought to connect with the head. 



