n
close connexion with this part--at other times, at some distance from
it, according as the neck may happen to be wide and near the vessel, or
narrow, and removed from it nearer to the median line. At the external
ring, H, (Plate 34,) the sac of this hernia, g, protrudes on the inner
side of the spermatic vessels, f; and the size of the hernia distending
the ring, removes these vessels at a considerable interval from, I, the
crista pubis. At the ring, H, (Plate 34,) the investments, g f, of the
direct hernia are not always distinct from those of the oblique hernia,
g f, (Plate 33); for whilst in both varieties the intestine and the
spermatic vessels are separated from actual contact by the sac, yet it
is true that the direct hernia, as well as the oblique, may occupy the
inguinal canal. It is in relation to the epigastric artery alone that
the direct hernia differs essentially from the oblique variety; for I
find that both may be enclosed in the same structures as invest the
spermatic vessels.

The external ring of the male groin is larger than that of the female;
and this circumstance, with others of a like nature, may account for the
fact, that the female is very rarely the subject of the direct hernia.
In the male, the direct hernia is found to occur much less frequently
than the oblique, and this we might, a priori, expect, from the
anatomical disposition of the parts. But it is true, nevertheless, that
the part where the direct hernia occurs is not defended so completely in
some male bodies as it is in others. The conjoined tendon, which is
described as shielding the external ring, is in some cases very weak,
and in others so narrow, as to offer but little support to this part of
the groin.

DESCRIPTION OF THE FIGURES OF PLATES 32, 33, & 34.

PLATE 32.

A. That part of the ilium which abuts against the sacrum.

B. The spine of the ischium.

C. The tuberosity of the ischium.

D. The symphysis pubis.

E. Situation of the anterior superior iliac spine.

F. Crest of the ilium.

G. Iliacus muscle.

H. Psoas magnus muscle supporting the spermatic vessels.

I. Transversalis muscle.

K. Termination of the sheath of the rectus muscle.

L1 L2 L3. The iliac, transverse and pelvic portions of the transversalis
fascia.

M M. The peritonaeum lining the groin.

N. The epigastric vessels lying between the peritonaeum, M, and the
transversalis fascia, L2. O. The umbilical ligament.

P. The ne