130 
F. MA.URI. 
its direction breaks the curve described in its whole by the 
inguinal ring. The anterior commissure is constituted by 
the angle formed by the pre-pubic tendon and the crural 
arch, as they are inserted upon the anterior border of the 
pubis. This is a point de repere and a precious guide for the 
operator, indicating as it does, positively, the actual position 
of the inguinal ring. 
The posterior commissure is not well defined, a result of 
the lesser resistance of the archiform fibres of the aponeuro¬ 
sis of the great oblique muscle, which form it, and which 
cover the small oblique whose fibres are also quite loose. 
Thus made up, the inguinal ring is the opening ending the 
inguinal canal below and through which the hand of the 
when passed out of the inguinal canal, come to occupy their 
normal position in the testicular bags. 
(i b ) The inguinal tract or interstice, thus so happily named 
by Mr. Degires, because in cryptorchids there is as yet no in¬ 
guinal canal, is situated between the posterior border of the 
small oblique of the abdomen and the crural arch. It is 
neither a canal nor an empty space, but simply an interstice, 
completely closed, and filled by loose cellular tissue. It runs 
obliquely from above downward, from before backward, and 
from without inward, and extends from the superior quarter 
of the crural arch, where a part of the fleshy fibres of the 
small oblique are inserted on the inguinal ring. About seven 
inches long it is closed above by the peritoneum, which rests 
on its edges, and is filled up by the sub-peritoneal connective 
tissue, which is continuous with that of the tract itself, and 
which becomes more loose and abundant as it approaches the 
inguinal ring. 
It is very important, in a surgical point of view, to avoid 
misunderstanding the inguinal interstice and confounding it 
with the inguinal canal. At first, it seems to indicate the 
direction of the latter, if it existed, and the proper one to fol¬ 
low in searching for the testicle in abdominal ectopia. But 
the inguinal canal, constituted by the vaginal sheath, is situ¬ 
ated on the side of the pre-pubic region at the lower part of 
