442 ANGIOLOGY. 



the internal surface of the leg. It ascends, and terminating near 

 the groin, may either pass through the interstice between the 

 gracilis and sartorius muscles, entering the femoral vein ; or it 

 may end, near the origin of the gracilis, by joining the external 

 pudic veins. 



The EXTERNAL SAPHENA or VENA SAPHENA MINOR, originates 

 at the front of the os calcis, anastomosing with the posterior root 

 of the internal saphenic, with which, above the hock and in f/ont 

 of the calcaneum, it forms a large plexus of veins. It also anas- 

 tomoses with the posterior tibial vein, by a large branch which 

 passes between the tibia and flexor pedis perforans ; and it runs 

 along the tendon of the gastrocnemius, in company with a nerve, 

 terminating near the stifle joint in the popliteal vein. 



The POPLITEAL vein, formed by the union of the anterior and 

 posterior tibials, is a satellite of the popliteal artery, and receives 

 branches corresponding to those given off from the latter. 

 The principal one is the femoro-popliteal, which enters with the 

 external saphenic vein. 



The FEMORAL vein, a satellite of the artery, is the continuation 

 of the popliteal. Its branches are similar to those of the femoral 

 artery, with the addition of the internal saphena, which joins 

 about its middle third. The femoral terminates in the external 

 iliac vein. 



The EXTERNAL ILIAC is thus the continuation of the femoral 

 vein ; and is the larger of the two branches which form the 

 common iliac. In its course, this vein, which commences at the 

 pubis, receives no important collateral branches, excepting the 

 circumflex vein of the ilium, a satellite of the corresponding 

 artery. 



INTERNAL ILIAC VEIN. 



(FiG. 165. &".) 



The internal iliac vein, which, with the external, forms the 

 common iliac trunk, is very short, and formed by the union of 

 satellites, corresponding to the branches given off from the inter- 

 nal iliac artery. 



ANTERIOR VENA CAVA. 



(Fio. 167. 1, 1.) 



The anterior vena cava is the venous trunk, which returns the 

 blood chiefly from the head, neck, fore extremities, and part of 



