ANGEIOLOGY. 101 



posterior saphena vein, with numerous branches : ascending obliquely 

 inwards, it passes through the opening in the tendon of the triceps to 

 become the 



Femoral Vein, which is joined in the groin by the profunda and saphena 

 veins to form the 



External Iliac Vein. This extends from Poupart's ligament to the 

 ilio-sacral symphysis, where it meets the internal iliac to form the common 

 iliac. It also receives the trunk of the epigastric veins, and of the two 

 circumflex ilii. 



The Internal Iliac Vein accompanies the artery in its inner side ; it is 

 formed by the union of several veins corresponding to the branches of the 

 internal iliac artery, viz. obturator, pitdic, sciatic, glutceal, &;c. 



The Common Iliac Veins are formed by the union of the two internal 

 and external, opposite each ilio-sacral symphysis. Ascending, they meet at 

 an acute angle, opposite the fourth intervertebral ligam.ent to the right side 

 of and a little below the division of the aorta. Their union constitutes the 

 inferior or ascending vena cava. 



The Inferior Vena Cava, thus constituted, ascends along the right sid(5 

 of the aorta, passes through the diaphragm, and opens into the lower and 

 back part of the right auricle. It receives the lumbar, spermatic, renal or 

 emulgent, capsular or supra-renal, inferior phrenic, and the hepatic veins. 

 The inferior cava is larger than the superior ; it returns the blood from al I 

 parts of the body below the diaphragm, collecting that of the portal system 

 through the medium of the hepatic veins. 



PL 136, fig. 1 ", hepatic vein ; ", internal spermatic ; ", supra-renal ; 

 *', renal veins; ", connecting branch between the renal and common iliac 

 veins; "•", lumbar veins; ", common iliac; '"', femoral; ", hypogastric; 

 «9,20,30^ lateral and middle sacral veins. 



PI. 134, fig. 7 ', internal saphena vein ; ^, exterior epigastric ; ', an acces- 

 sory, and *, a principal branch of the internal saphena. Fig. 8 ', course of 

 the internal saphena on the inside of the leg ; '', its commencement on the 

 back of the foot. Fig. 9, ])lexus on the back of the foot. Fig. 10 ', exter- 

 nal saphena ; ^ internal do. 



4. The Portal System. 



The portal system constitutes a peculiar vascular arrangement in the liver 

 for the purification of the blood and the secretion of the bile. The portal 

 vein, or vena porta, although it arises in the abdomen as a vein, and serve.n 

 the same office, yet terminates in the liver like an artery, and has a secreting 

 function ; it returns the blood from all the chylopoietic viscera, to be dis- 

 tributed through the liver, and in the latter organ it receives the venous 

 blood from the termination of tlie hepatic artery. It is four or five inche»s 

 long, and is formed by the confluence of the splenic and mesenteric veins 

 behind the pancreas. Ascending obliquely, it receives branches from the 

 pancreas, duodenum, stomach, and gall-bladder, and enters the left extremity 



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