THE THIGH 229 



general arrangement of the lymph vessels may also be made 

 out. To the subinguinal group of glands proceed the super- 

 ficial lymph vessels of the lower extremity, and lymph vessels 

 from the external genitals, the perineum, and the lower part 

 of the abdominal wall. These are termed the afferent vessels. 

 In addition to them, numerous other vessels connect the 

 glands with one another. The lymph vessels which lead the 

 lymph away from the glands are called the efferent vessels. A 

 large number of them pass through the fossa ovalis, others 

 pierce the fascia lata. They join the deep subinguinal glands 

 and the external iliac glands, which lie in relation to the 

 femoral and external iliac arteries (Figs. 159, 160). 



Fossa Ovalis. The fossa ovalis is an aperture in the deep 

 fascia of the thigh, through which the great saphenous vein 

 passes before it pierces the femoral sheath and joins the 

 femoral vein. The fossa lies in the upper and medial angle 

 of the front of the thigh, its centre being situated about 

 37 mm. lateral and distal to the pubic tubercle (Fig. 106). 

 It is bounded, laterally, by a thin curved margin, the margo 

 faldformis. The margo falciformis is the medial margin of the 

 more lateral portion of the fascia lata, which, because it is 

 attached to the inguinal ligament superficial to the iliacus 

 muscle, and the anterior part of the iliac crest, is called the 

 iliac part of the fascia lata. The proximal end of the margo 

 falciformis is the superior cornu (Fig. 106). It turns medially 

 to gain attachment to the pubic tubercle and to the 

 ligamentum lacunare, and so forms the proximal boundary 

 of the fossa. The distal end of the margo falciformis also 

 turns medially, forming the inferior cornu, which lies posterior 

 to the upper end of the great saphenous vein, on the medial 

 side of which it terminates by blending with \\\z pectineal part 

 of the fascia lata, so called because it ascends superficial to 

 the pectineus muscle to the pectineal line of the pubis 

 (Figs. 1 06, 113). The manner in which the fascia lata 

 surrounds the muscles of the proximal part of the inferior 

 extremity, so that the iliac portion lies anterior to the 

 femoral sheath and the pectineal portion passes posterior to 

 the sheath, is shown in the section represented in Fig. 113. 



The fossa ovalis is closed by the cribriform fascia, a thin 

 stratum of the fascia lata which passes from the falciform 

 margin and the cornua to the pectineal fascia. The cribri- 

 form fascia is pierced by the great saphenous vein, the 



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