THE VEINS. 315 



superficially. It passes onto the dorsal surface of the foot and 

 becomes connected with terminal branches of A. saphena. 



(L A. tarsea medialis. — This arises from the tibialis an- 

 terior just distad of the transverse ligament through which 

 it passes at the ankle, passes over the medial surface of 

 the astragalus, and is distributed to the ligaments about the 

 ankle-joint. It anastomoses with the plantar branch of A. 

 saphena. 



c\ A. metatarsea. — The metatarsal artery passes laterad 

 from the tibialis anterior at the distal boundary of the tarsus, 

 on the dorsal surface of the foot. It sends branches distad in 

 the intervals between the third and fourth and the fourth and 

 fifth metatarsals. 



The distal branches (Fig. 1 28) of the tibialis anterior have 

 been described in the general description of the artery. 



THE VEINS. VENiE. 



"Venae pulmonales. The Pulmonary Veins. 



The pulmonary veins follow in the lungs the course of the 

 bronchi. They enter the left auricle in three groups (Fig. 

 1 16, page 276). The first of these (/) comes from the anterior 

 and middle lobes of the right side, the second (//) from the 

 corresponding lobes of the left side, and the third (^) from the 

 terminal lobes of both sides. Each group is composed of two 

 or three veins and opens into a sinus or extension of the auricle. 

 The sinuses are from their position dextral (/), sinistral (//), 

 and dorsal {g). 



The Veins of the Body. 



The veins of the body may be classified into three main 

 groups: (i) the veins of the heart; (2) the superior vena cava 

 and its branches ; (3) the inferior vena cava and its branches. 

 The portal system of veins will be considered with the inferior 

 vena cava. 



I . Veins of the Heart. 



The veins of the heart consist of one large vein, the vena 

 cordis magna, and a number of small veins. 



