If the finger is passed up from the tuberosity along
the inner wall of the pelvis, the pudic vessels (if
injected) will be felt about three-fourths of an inch up.
The student will also notice, when both ischio-rectal
fossse are cleaned out, that there is no communication
between the two, owing to the median fibrous septum
which divides them.
This fibrous tissue, where it joins the anus to the
coccyx, is called the ancMsoccygeal ligament, and, in
front of the rectum, the central tendon of the perinseum.
Emerging from under the edge of the gluteus maxi-
mus, about an inch outside the ischial tuberosity, will
be found the long pudendal branch of the lesser sciatic ;
it can be traced forwards as far as the scrotum.
When the fat in which this nerve lies has been
removed, another layer of fascia will be exposed, which
is seen to be attached on each side to the ramus of the
pubes and ischium, and to turn downwards behind to



132 The Dissector's Manual. [Chap. v.
form the front boundary of the ischio-rectal fossa. It
there becomes continuous with what has been already
described, but not yet Seen, the triangular ligament.
In front it can be traced up to become continuous
with the fascia of the abdomen.
It is very easy, if great care be not taken, to
remove this layer of fascia along with the fat which
lies upon it. To avoid doing so, the student should
scrape with the handle of his scalpel at the border o^
the rami of the pubes, as by so doing he will run less
chance of wounding the fascia.
