778 A MANUAL OF ANATOMY 



the subperitoneal areolar tissue (Abernethy's fascia), which binds 

 the artery with its vein to the iliac fascia, the external iliac vein 

 (except for a short distance above on the right side, where the 

 vein is behind its artery), and the vas deferens near Poupart's 

 ligament. 



Branches. — These are as follows : muscular to the psoas magnus ; 

 glandular to the external iliac glands (both unimportant) ; deep 

 epigastric; and deep circumflex iliac. For the latter two, see 

 pp. 662, 663. 



Varieties of the Branches. — (i) The origin of the deep epigastric may be 

 transferred to the common femoral, or to the arteria profunda femoris, and the 

 deep circumflex iliac may be transferred to the common femoral. (2) The 

 internal circumflex, obturator, or arteria profunda femoris may arise from the 

 external iliac, in which latter case two large arteries would emerge on to the 

 thigh beneath Poupart's ligament. 



The external iliac vein is the continuation of the femoral 

 vein. It extends from the lower border of Poupart's ligament to 

 the sacro-iliac articulation on a level with the brim of the pelvis, 

 where it joins the internal iliac, and so forms the common iliac vein. 

 The right vein lies at first internal to its artery, and then behind it. 

 The left vein lies internal to its artery throughout. Its chief tribu- 

 taries are the deep epigastric and deep circumflex iliac veins. 



The external iliac vein of adult life is preceded in function by the sciatic 

 vein of the embryo, which is the primitive vein of the lower limb. In the 

 process of development the upper part of the femoral and the whole of the 

 external iliac vein of the adult are continued upwards from the long saphenous 

 vein to the cardinal portion of each common iliac vein, and the sciatic vein is 

 now a tributary of the internal iliac. 



Collateral Circulation. — When the external iliac artery is ligatured, the 

 collateral circulation is carried on through the following channels : ( i ) the 

 superior epigastric of the internal mammary from the first part of the subclavian 

 anastomoses with the deep epigastric of the external iliac ; (2) the pubic 

 branch of the obturator from the internal iliac anastomoses with the pubic 

 branch of the deep epigastric ; (3) the ilio-lumbar and gluteal, both from the 

 internal iliac, and the abdominal branches of the lumbar arteries from the 

 aorta anastomose with the deep circumflex iliac of the external iliac ; (4) the 

 obturator from the internal iliac anastomoses with the internal circumflex of 

 the arteria profunda femoris ; ( 5 ) the sciatic from the internal iliac anastomoses 

 with the internal and external circumflex, and the first perforating of the 

 arteria profunda femoris ; (6) the gluteal anastomoses with the external 

 circumflex and the ascending branch of the internal circumflex from the arteria 

 profunda femoris ; (7) the arteria comes nervi ischiadici of the sciatic anasto- 

 moses with the perforating branches of the arteria profunda femoris ; and 

 (8) the superficial perineal and dorsalis penis of the internal pudic from the 

 internal iliac anastomose with the superior and inferior external pudics of the 

 common femoral. 



External Iliac Lymphatic Glands. — ^These glands are related to 

 the external iliac vessels, and are about twelve in number. They are 

 usually arranged in three chains — outer, middle, and inner — there 

 being about four glands in each chain. The outer chain lies on the 



