Testes.—Thesè glands are situated external to the kidney, but do not reach quite
so far as that organ and rest on the depressor muscles of the tail and on the transver-
salis abdominis. Their form appears to vary with âgé and functional activity; In one
specimen caught on the 14th August the testicle presents three surfaces and is deepest
from the dorsal to the ventral margin. The surface looking inwards towards the
middle line is broad and slightly concave, and the one external to it is convex and
narrowly crescentic and is directed ventrally, whilst the dorso-lateral surface is
also broad but convex, and marked at its hinder end by a deep pit. I t is 4 inches
long, 3 broad across the concave face, and 2 inches in thickness from the ventral
to the dorsal surface. In this specimen, the head of the epididymis covers the
anterior and external surfaces of the upper extremity. The body and globus minor
of the epididymis are dorso-lateral and external. In an individual captured on the
18th July, the testicle is a flattened oval, or nearly so, with only two surfaces, an inner
and outer, and a continuous margin, its greatest thickness not exceeding 1 inch.
The head of the epididymis is confined to the upper extremity, while the body is
placed along the inner margin of the surface.
The epididymis, when dissected off the testicle in both, is seen to be made up
of five distinct sections ; first, the head with the vasa efferentia, the former consisting
of two portions, one of which is smaller than, and overlays, the other ;
second, the body, which is thin and leaf-shaped ; third, another thin but irregularly
shaped part eccentric to the coil that connects it with the portions on either side
of it, and with a short process projecting from its extremity and applied, to the
back of the testicle ; fov/rth, a long, rather rounded oblong part connected by a
pedicle to a short thick flattened trowel-like piece, which constitutes the fifth
and last division or tail. The total length of the masses of the aggregated
coils of the seminal tube is 16 inches, exclusive of the eccentric division,
and it is probable that if the whole were uncoiled that it would extend to 30 or
40 feet.
Vasa efferentia.—These emerge on the internal surface of the testicle near its
anterior end, and the orifices of thirteen tubes can be detected, when the structures
are cut away close to the tunica albuginea. The vasa efferentia consist of four
kinds : first, a simple convoluted tube ; second, tubes with appended cæca ; third,
united divergently simple ducts with basal branched cæca ; and fourthly, blind cæca
or aberrant vasa efferentia. The first is about 3 inches in length and is much
coiled; the second may have one or more small cæca at its base, either communicating
with its canal or opening by separate orifices into the testicle. The third
form consists of two portions* first two vasa efferentia, one with appended cæca, and
the other simple and separate from the former at the point of divergence from the
gland, but united beyond the cæca in a common tube ; this afterwards forming
two ducts. Two of the cæca lie side by side with separate canals, but the one
next the duct gives off a branch which enters it below the point, where it unites
with its fellow. The fourth description comprises either simple or branched
cæca communicating with the testicle, each by an opening of its own. These
are aberrant vasa efferentia, and the other unbranched cseca may be regarded in the
same light.
Vas deferens.—This passes off from the epididymis at its outer and posterior
extremity to reach the body, bending on itself to do so. I t leaves the anterior
extremity of the tail on a line with the lower end of the testicle along the free
margin of the fold of the peritoneum, which stretches across the pelvic portion of
the abdominal cavity and connecting the testes. I t has the ureter behind it as it
leaves the epididymis, and in the mesial line is in close contact with its fellow of
the opposite side. Thence it suddenly turns backwards along the. side of the contracted
bladder and is crossed by the ureter immediately above the point of its
attachment to that viscus. Beyond that locality it passes downwards and inwards
and perforates the wall of the prostatic portion of the urethra about 0‘75 inch above
the caput gallinaginis to terminate on it as the seminal duct.
Caput gallinaginis.—This is situated on the back wall of the prostatic portion
of the urethra, and the longitudinal ridge from the uvula vescise is continued with
it. I t depends on the floor of the urethra below it, and has a rather deep recess on
either side of it, in which the ducts of the prostate are situated. I t is 0‘30 inch
in length and iff breadth, and 0-25 in height. Its extremity is surrounded by a
fringe of mucous membrane which seems to assist in closing the two orifices of
the seminal ducts, one of which is placed'on either side of its free extremity with
the sinus pocularis between and rather posterior to them. They are rounded
orifices placed on either side of a thin partition, the free endi of which expands
from before backwards into a somewhat elongatedly rounded membrane with
a rather tumid edge, and in the centre of which is the very shallow depression,
the sinus pocularis. I t is little more than 0*02 inch in depth, and when the
two halves of the tumid edge are opposed like lips to the sinus, it cannot be
detected.
Mammary organs.—In the male the mammae are situated 030 inch in front
of the vent, with an interval between them of 0'25 inch. The nipple is freely exposed
on the surface, and is a short rugose cylindrical structure O'25 inch in diameter, and
0*30 inch in height. Its tip is pale yellowish, perforated at the apex by a single
orifice and more or less .flattened and rugose. The gland is a small honeycombed
structure, 0*30 inch long, and 1 inch in diameter, surrounded by a ring of fine
muscular fibres derived from the superficial sphincter of the anus. The area around
the anus is highly vascular; the orifice is transverse and the outer skin thrown into
numerous cross folds.
Tn the female, the nipple is situated at the base of a deep pit, about an inch
anterior and external to the anus (PI. XXI, fig. 1, m), 0*45 inch in depth, and 0’50
inch in longitudinal diameter. The nipple itself is a small conical structure compressed
laterally, about 0*20 inch in height by 0-30 inch in its longitudinal length, and
0*15 broad in its transverse section. I t is perforated at its apex by a single orifice
that admits the passage of a probe.. The canal in question is very short, not more
than 0-20 inch in length, but it is very extensile. I t .commences at the posterior