THE VEINS 211 



The External Sapherm Vein. — This vein begins at the hock on the 

 outer aspect of the os calcis, where it communicates with the posterior 

 root of the internal saphena vein through a network of small veins 

 which runs across the front of the tuber calcis. It also communicates 

 with the posterior tibial vein. It is very superficially placed and passes 

 upwards along the outer side, and slightly in front of the tendon of the 

 gastrocnemius muscle, following the course taken by the external 

 saphena nerve. It communicates with the femoro-popliteal vein and 

 terminates by joining the popliteal vein. 



The Popliteal Vein. — This vein is formed by the union of the anterior 

 and posterior tibial veins, and runs up the posterior face of the posterior 

 common ligament of the stifle joint alongside the popliteal artery, where 

 both are covered by the popliteus muscle. 



The Femoral Vein. — This is the upward continuation of the popliteal 

 vein, and is in turn continued upwards as the external iliac vein. It 

 follows the course taken by the artery of the same name, and receives 

 affluent vessels which are satellites of the branches of the artery. 

 In addition it receives the internal saphena vein, and the prepubic 

 vein. 



The Internal Iliac Vein. — The satellite veins of the branches of the 

 homonymous artery unite and form a short trunk which forms the 

 common iliac vein by joining the external iliac, or they may open 

 directly into the common iliac vein. 



The External Iliac Vein. — This is the continuation of the femoral 

 vein, and it forms the chief root of the common iliac vein, of which the 

 internal iliac may be regarded as a collateral affluent. It begins at the 

 brim of the pelvis and runs upwards behind the artery, receiving during 

 its course the circumflex-iliac vein. 



The Common Iliac Vein. — This is found between the internal and 

 external iliac arteries, and is a vein of considerable size. Of the two 

 veins the left is the longer, and it is related above to the body of 

 the last lumbar vertebra and below to the posterior extremity of the 



