206 



ANATOMY AND PHYSIOLOGY 



The external jugular vein empties into the subclavian at about the middle 

 of the clavicula. It is easily seen through the platysma muscle. 



Superficial. From fore arm; 

 groups of veins, both anterior and 

 posterior, form two, called the basilic 

 and cephalic, which empty into the 

 axillary vein. 



Median veins in front of the elbow con- 

 nect the basilic and the cephalic (Fig. 142). 



The subclavian, having gathered 

 blood from the entire upper extrem- 

 ity, unites with the internal jugular 

 to form the anonyma vein; the an- 

 onyma veins (right and left) unite to 

 form the superior vena cava (Fig. 

 127). 



The left anonyma vein is the 

 longer of the two, since it must 

 cross to the right side to join the 

 right vein. 



The Superior Vena Cava 



The superior vena cava is formed 

 by the union of the two anonyma 

 veins. It lies on the right side of 

 the arch of the aorta, and opens into 

 the right atrium of the heart 

 (Fig. 126). 



Great 



or long 



saphena 



vein 



VEINS OF THE THORAX 

 Blood from all of the intercostal 

 veins (except in the first space) 

 finally reaches the great azygos vein, 

 which opens into the superior vena 

 cava (Fig. 135, azygos major). 



The blood of the heart itself is 

 returned directly to the right atrium 

 by a coronary vein called the coronary 

 sinus. All other thoracic organs return their blood to azygos 

 veins and these to superior vena cava. 



FIG. 144. SUPERFICIAL VEINS, 

 ANTERIOR. 



