th 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.

On removing the peritonaeum from the inguinal wall on the inner side of
the iliac vessels, K L, we find the horizontal branch of the os pubis,
and the parts connected with it above and below, to be still covered by
what is called the subserous tissue. The femoral ring is not as yet
discernible on the inner side of the iliac vein, K; for the subserous
tissue being stretched across this aperture masks it. The portion of the
tissue which closes the ring is named the crural septum, (Cloquet.) When
we remove this part, we open the femoral ring leading to the
corresponding canal. The ring is the point of union between the fibrous
membrane of the canal and the general fibrous membrane which lines the
abdominal walls external to the peritonaeum. This account of the
continuity between the canal and abdominal fibrous membrane equally
applies to the connexion existing between the general sheath of the
vessels and the abdominal membrane. The difference exists in the fact,
that the two outer compartments of the sheath are occupied by the
vessels, whilst the inner one is vacant. The neck or inlet of the
hernial sac, H, Fig. 2, Plate 43, exactly represents the natural form of
the crural ring, as formed in the fibrous membrane external to, or (as
seen in this view) beneath the peritonaeum.

The femoral ring, H, is girt round on all sides by a dense fibrous
circle, the upper arc being formed by the two femoral arches; the outer
arc is represented by the septum of the femoral sheath, which separates
the femoral vein from the canal; the inner arc is formed by the united
dense fibrous bands of the conjoined tendon and Gimbernat's ligament;
and the inferior arc is formed by the pelvic