106 ANATOMY FOE NURSES. [CHAP. IX. 



with valves than the veins of the upper limbs. The deep veins 

 accompany the arteries. The two largest superficial veins are 

 the internal or long saphenous, and the external or short saphenous 

 vein. The internal saphenous extends from the ankle to within 

 an inch and a half of Poupart's ligament. It lies along the 

 inner side of the leg and thigh, and terminates in the femoral 

 vein. The external saphenous arises from the sole of the foot, 

 and, passing up the back of the leg, ends in the deep popliteal. 



Both deep and superficial veins pour their contents into the 

 external iliac. The blood is returned from the pelvis by the 

 internal iliac veins, which, uniting with the external iliac, form 

 the two common iliac veins. Extending from the base of the 

 sacrum to the fourth lumbar vertebra, the two common iliacs 

 unite to form the inferior vena cava. 



The inferior or ascending vena cava returns the blood from 

 the lower limbs, pelvis, and abdomen. It begins at the junction 

 of the two common iliacs, and thence ascends along the right 

 side of the aorta, perforates the diaphragm, and terminates by 

 entering the right auricle of the heart. The inferior vena cava 

 receives many tributaries, the chief of which are the lumbar, 

 ovarian, renal, and hepatic veins. 



The pulmonary artery. The pulmonary artery conveys the 

 dark blood from the right side of the heart to the lungs. The 

 main trunk is a short, wide vessel (diameter 30 mm.) which 

 arises from the right ventricle and runs for a distance of two 

 inches backwards and upwards (vide fig. 63). Between the 

 fifth and sixth dorsal vertebrae, it divides into two branches, 

 the right and left pulmonary arteries, which pass to the 

 right and left lungs. 



The pulmonary veins. The pulmonary veins are four short 

 trunks which convey the red blood from the lungs to the left 

 side of the heart, and which are found two on each side in 

 the root of the corresponding lung. The pulmonary veins have 

 no valves. 



