The sheath, e f, of the femoral vessels, E F, Fig. 1, Plate 43, passes from beneath the middle of the femoral arch. In this situation, the iliac part of the fascia lata, F G, Fig. 2, Plate 44, covers the sheath. Its inner side is bounded by Gimbernat's ligament, R, Fig. 1, Plate 44, and F, the falciform edge of the saphenous opening. On its outer side are situated the anterior crural nerve, and the femoral parts of the psoas and iliacus muscles. Of the three compartments into which the sheath is divided by two septa in its interior, the external one, E, Fig. 1, Plate 43, is occupied by the femoral artery; the middle one, F, by the femoral vein; whilst the inner one, G, gives passage to the femoral lymphatic vessels; and occasionally, also, a lymphatic body is found in it. The inner compartment, G, is the femoral canal, and through it the femoral hernia descends from the abdomen to the upper and forepart of the thigh. As the canal is the innermost of the three spaces inclosed by the sheath, it is that which lies in the immediate neighbourhood of the saphenous opening, Gimbernat's ligament, and the conjoined tendon, and between these structures and the femoral vein. The sheath of the femoral vessels, like that of the spermatic cord, is infundibuliform. Both are broader at their abdominal ends than elsewhere. The femoral sheath being broader above than below, whilst the vessels are of a uniform diameter, presents, as it were, a surplus space to receive a hernia into its upper end. This space is the femoral or crural canal. Its abdominal entrance is the femoral or crural ring. The femoral ring, H, Fig. 2, Plate 43, is, in the natural state of the parts, closed over by the peritonaeum, in the same manner as this membrane shuts the internal inguinal ring. There is, however, corresponding to each ring, a depression in the peritonaeal covering; and here it is that the bowel first forces the membrane and forms of this part its sac.