VI VEINS 85 



into two branches. One of these is the pelvic vein already 

 seen ; it unites with the corresponding vessel of the opposite 

 side to form the abdominal vein {abd). The other branch of 

 the femoral is called the renal portal vein (rn.pt) ; it passes 

 directly forwards, receiving the sciatic vein (sc) from the back 

 of the leg, and then goes along the outer border of the 

 kidney, finally branching out in that organ. It also receives 

 a large vein {ds. ImS) from the muscles of the back. 



The abdominal vein receives, near its posterior end, 

 small veins (pes) from the urinary bladder. It passes 

 forwards, as already seen, receiving veins from the abdo- 

 minal muscles, and, quite at its anterior end, a small vein 

 (cd) from the heart. It then divides kite two branches 

 which enter the liver and branch out in that gland. 



The veins from the stomach (gs), the intestine (du, int), 

 spleen {spl), and pancreas run in the mesentery alongside 

 the corresponding arteries. Near thfe liver they all unite to 

 form a large vessel, the hepatic portal vein {hp.pt), which 

 enters and branches out into the liver, first sending off a 

 branch which joins the abdominal. 



Thus the veins from all parts of the body, except the 

 lungs, ultimately discharge into the sinus venosus. The 

 veins from the lungs are quite singular in their course ; they 

 unite, in each lung, to form a single pulmonary vein {pul), 

 which passes behind, or dorsal to, the sinus venosus, and 

 discharges, with its fellow of the opposite side, into the left 

 auricle. 



Character of the Blood in the Arteries and Veins. — There 

 are certain differences between the arteries and veins in 

 respect of the blood they contain. As a rule, the veins 

 contain purple or non-aerated blood, the arteries more or 

 less thoroughly aerated or scarlet blood. But there are 

 certain exceptions. As we shall see in a later chapter, the 



