VEINS OF THE LOWER EXTREMITIES. 261 



mination of the 'axillary to the vena innominata, where the 

 latter is constituted by the junction of the internal jugular with 

 the subclavian. In its course it goes under the subclavian mus- 

 cle, and is in front of the subclavian artery from the beginning, 

 but near it: afterwards it is separated from the artery by the 

 latter going between the anterior and the middle scalenus mus- 

 cle; whereas the vein runs over the anterior end of the first 

 rib, in front of the insertion of the scalenus anticus. 



The Subclavian Vein is joined by some branches coming 

 from the shoulder and from the lower part of the neck; and, at 

 the outer margin of the origin of the sterno-mastoid muscle, it 

 is augmented by the addition to it of the external jugular. It 

 terminates at the internal margin of the scalenus anticus, as 

 mentioned in the vena innominata. 



SECT. III. VEINS OF THE LOWER EXTREMITIES. 



The veins of the lower extremities, like those of the upper, 

 are deep-seated and superficial. The former follow the course 

 of the arteries, and are the vena3 satellites; there being, for the 

 most part, two veins for every artery as far up as the ham, and 

 also as regards the muscular branches of the thigh. These vena3 

 satellites adhere closely to the artery, and are separated from 

 each other by the latter. They also have frequent anastomoses 

 with each other across the artery. 



The Popliteal Vein (Vena Poplitea) is a single trunk formed 

 by the union of the anterior tibial, the posterior tibial, and the 

 peroneal veins. It begins on the posterior part of the head of 

 the tibia, and extends upwards through the ham to the perfora- 

 tion in the adductor magnus muscle, which transmits the femo- 

 ral artery. It is situated on the posterior face of the popliteal 

 artery, to which it closely adheres; and behind it is the popliteal 

 nerve, the continuation of the great sciatic. 



The Femoral Vein (Vena Femoralis) is the continuation up- 

 wards of the popliteal : it at first is placed behind the artery, 

 but in a short space it gets to its interior face, and continues to 

 adhere to it, in that situation, up to Poupart's ligament, where 



