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known as the interstitial cells of the testis, and have been regarded as specially
modified connective tissue cells (plasma-cells, Waldeyer), or as epithelial cells derived
from the Wolffian body (Klein), but until their development has been fully traced,
nothing certain with regard to their nature can be stated. In sections of the foetal
testis, the cells in question are not distinguishable from the other cells of the develop-
ing intertubular connective tissue. Similar cells are met with in the stroma of the

The capillaries form a close network over the walls of the seminiferous

The nerves of the testis appear not to be provided with ganglia, as is the case
with most of the visceral nerves, nor have they been traced into the interior of the
seminiferous tubules, but they ramify over the tubules and many are distributed
to the blood-vessels.

Ducts of the testis. As the convoluted tubuli seminiferi approach the medi-
astinum testis they unite, as before said, with one another at acute angles into a
smaller number of tubes which have a less flexuous course, and at length become
nearly straight. Close to the mediastinum they taper into short, straight tubes
(tubuli recti), of smaller diameter than the seminiferous tubes, and differing from
them in the character of their epithelium (fig. 245). This, in the straight tubules,
is a single layer of flattened or cubical cells continuous with the outer or lining cells
of the seminiferous tubes. The basement membrane is also continued on to the
straight tubules.

The straight tubules open into a network of vessels which lies in the fore part of
the mediastinum, and was named by Haller, rete vasculosum testis (fig. 245, c).
The tubes composing the rete have no proper walls, but are merely channels in the
fibrous stroma, lined by flattened epithelium. Their diameter is greater than that of
the tubuli recti. The secretion from the testis is accumulated in the rete testis, and
is conducted to the upper and back part of the testis, whence it is conveyed away
by Lhe efferent tubules, or vasa efferentia. These are from twelve to fifteen, or



sometimes twenty in number ; they perforate the tunica albuginea beneath the
globus major of the epididymis, of which they may be said to form a part, and in
the convoluted canal of which they ultimately terminate. On emerging" from the
testis, these vasa efferentia are straight, but, becoming more convoluted as they
proceed towards the epididymis, they form a series of small conical masses, the
bases of which are turned in the same direction, and which are named coni vasc/ulosi



a, seminiferous tubules ; b, fibrous strorna continued from the mediastinum testis ; c, rete testis.


a, body of the testicle ; b, tubuli in the interior of the gland ; c, rete vasculosum ; d, vasa
efferentia terminating in the coni vasculosi ; e, f, q, convoluted canal of the epididymis ; h, vas
deferens ascending from the globus minor of the epididymis.

(figs. 237, 246). They are about 0'5 mm. in diameter. The largest of the cones is
about 14 mm. long, and when unrolled, each is found to consist of a single coiled
duct, varying from 150 mm. to 200 mm. in length, and the diameter of which
gradually decreases from the testis to the epididymis (Huschke). Opposite the
globus major these separate efferent vessels open, at intervals which, in the un-
ravelled tube, are found to be about 75 mm. in length, into a single canal or duct,
the intervening and subsequent convolutions of which constitute the epididymis itself.
The canal of the epididymis (fig. 240, e.f,g) is disposed jn very numerous coils,
and extends from the globus major downwards to the globus minor or tail, where,
turning upwards, it is continued on as the vas deferens. "When its complicated
flexuosities are unrolled, it is found to be twenty feet (6 or more metres) in
length. The smallest windings are supported and held together by fine areclar



tissue ; but, besides this, numerous incomplete, transverse, fibrous partitions aiv.
interposed between larger masses of the coils, which have been named the lobes of
the epididymis. The canal of the epididymis is, at its commencement, about
4 mm. in diameter, but diminishing as it proceeds towards the globus minor, it is
about 0*27 mm., after which it again increases in size, and becomes less deeply con-
voluted as it approaches the vas deferens. Its coats, which are at first thin, become
thicker in its progress.

The vasa efferentia have a layer of circular muscular fibres, to which in the tube
of the epididymis is added an external longitudinal layer, both being relatively thin.

DEFERENS. (From Kb'lliker, after Arnold. ) f .

, body of the testicle ; b, lobules ; c, vasa recta ;
d, rete vasculosum ; e, vasa efferentia ; /, coni
vasculosi ; g, epididymis ; h, vas deferens ; i, vas
aberrans ; m, branches of the spermatic artery
passing to the testicle and epididymis ; n, ramifica-
tion in the testis ; o, artery of the vas deferens ;
p, its union with a twig of the spermatic artery.

The epithelial lining cells are columnar in
form, and are ciliated, the cilia being long,
and causing by their movement a current
towards the vas deferens. In the epidi-
dymis the cells are greatly elongated, in
the vasa efferentia they are shorter ; in
the lower part of the epididymis the cilia
disappear. Between the fixed ends of the
columnar cells other smaller cells are met

The vas deferens (fig. 247, h), or
excretory duct of the testis, forms the con-
tinuation upwards of the convoluted canal
of the epididymis. It commences at the
lower end of the epididymis, and, at first rather tortuous but afterwards becoming
straight, it ascends upon the inner side of the epididymis, and along the back of the
testicle, separated from both, however, by the blood-vessels passing to and from the
gland. Continuing then to ascend in the spermatic cord, the vas deferens accom-
panies the spermatic artery, veins and nerves, as far as the internal abdominal ring.
Between the testicle and the external ring its course is nearly vertical : it lies
behind the spermatic vessels, and is readily distinguished by its hard cord-like feel.
It then passes obliquely upwards and outwards along the inguinal canal, and reach-
ing the inner border of the internal abdominal ring, it leaves the spermatic vessels
(which extend to the lumbar region), and turns suddenly downwards and inwards
into the pelvis, crossing over the external iliac vessels, and turning round the outer
or iliac side of the epigastric artery. Running beneath the peritoneum, it reaches
the side of the bladder (fig. 249), upon which it descends, curving backwards and
downwards to the hinder surface of that viscus, and finally passes forwards to the
base of the prostate gland. In its course within the pelvis, it crosses over the cord
of the obliterated hypogastric artery, and lies to the inner side of the ureter.
Beyond this point, where it ceases to be covered by the peritoneum, it is attached to
the coats of the bladder, in contact with the rectum, and gradually approaching its
fellow of the opposite side. Upon the base of the bladder, the vasa deferentia are
situated between two elongated receptacles, named the seminal vesicles (fig. 249, s.v.) ;
and, close to the base of the prostate, each vas deferens ends by joining with the


duct from the corresponding seminal vesicle on its outer side to form one of the
common seminal or ejaculatory ducts (fig. 249, E.D.).

The vas deferens measures about a foot in length (300 mm:) r but when
extended and unravelled, about half as much again, or even more than this. In
the greater part of its extent it is cylindrical or slightly compressed, and has an
average diameter of about 2'5 mm., with a lumen of 0*7 mm. ; but towards its
termination, beneath the bladder, it becomes enlarged and sacculated, forming the
ampulla of Henle, and resembling in shape and structure a part of the seminal



a, epithelium ; b, mucous membrane ; c, d, e,
inner, middle, and outer layers of the muscular coat ;
/, bundles of the internal cremaster muscles ; </,
section of a blood-vessel.

vesicle. Previously to its junction with the
duct of that vesicle, it again becomes
naiTowed into a smaller and straight cylin-
drical canal. The walls of the vas deferens
are very dense and strong, and feel hard to
the touch, owing to the large proportion
their thickness bears to the inner cavity of
the tube. In the sacculated portion the
passage is muck wider, and the walls are
thinner in proportion. Small simple and
branched tubular glands beset the mucous
membrane of this portion of the duct (Henle).

Besides an external areolar investment,
and an internal mucous membrane, the vas
deferens is provided with an intermediate
thick muscular tunic, of a deep yellowish
colour. This coat consists of two layers

of plain fibres, an outer of longitudinal and an inner of circular fibres (fig. 248, d, e).
In addition, near the commencement of the tube is an internal longitudinal stratum,
extremely thin, and constituting not more than ith of the muscular coat (fig. 248, c);
in the ampulla, the inner longitudinal fibres are absent.

The lining membrane exhibits on its surface three or four longitudinal ridges,
and, besides this, in the sacculated portion of the duct, it is marked by numerous finer
rugae which enclose irregular polyhedral spaces, resembling in this alveolar character
the lining membrane of the seminal vesicles. The epithelium is of the columnar
kind, and not ciliated. As in the epididymis, there is a deeper layer of small cells
between the columnar cells.

According to Steiner the epithelium may be ciliated in parts, or it may show a character
similar to that of the ureter and bladder.

Vas aberrans. This name was applied by Haller to a long narrow tube, or diverticulum
(fig. 247, -/), discovered by him, and almost invariably met with, which leads off from the
lower part of the canal of the epididymis, or from the commencement of the vas deferens, and,
becoming tortuous and convoluted, is rolled up into an elongated mass which extends upwards
for an inch or more amongst the vessels of the spermatic cord, where the tube ends by a
closed extremity. Its length, when it is unravelled, ranges from about two to twelve or
fourteen inches ; and its width increases towards its blind extremity. Sometimes this
diverticulum is branched, and occasionally there are two or. more such aberrant ducts. Its
structure appears to be similar to that of the vas deferens. Its origin is probably connected
with the Wolffian duct of the fcetus, but the exact mode of its formation and its office are
unknown. Luschka states that occasionally it does not communicate with the canal of the
epididymis, but appears to be a simple serous cyst.



Roth has described other small blind vasa aberrantia lying- along the epididymis and
connected with the rete testis.

Org-an of G-iraldes. The small body thus named is situated in the front of the cord
immediately above the caput epididymis (see fig. 235, g). It consists usually of .several small
irregular masses containing convoluted tubules lined with columnar ciliated epithelium, and
is scarcely to be recognised until the surrounding connective tissue has been rendered
transparent by re-agents. It has also received the name of paradidyi&it (Waldeyer). Its
tubules appear to be vestiges of part of the Wolflian body.

The seminal vesicles are two membranous receptacles, situated, one on each
side, upon the base of the bladder, between it and the rectum. When distended, they
form two long sacculated bodies, somewhat flattened on the side next the bladder, to


THE PENIS, &C. (J. S )

B!, part of base covered by peri-
toneum, separated by a dotted line from
a triangular space left uncovered by that
membrane ; u, ureter ; s. v. , seminal
vesicle ; E. D. , ejaculatory duct ; v, pros-
tate ; M., membranous part of urethra ;
B, bulb ; c. s. , corpus spongiosum ; c. G.,
Cowper's gland.

which they arefirmlyattached,and
convex on their posterior surface ;
they are widened above and
narrow below (fig. 249, S. v.).
Their length is usually about two
inches (50 mm.), and the greatest
breadth about half an inch
(12'5mm.); but they vary both in
size and shape in different indi-
viduals, and also on the two sides.
Their upper obtuse extremi-
ties are separated widely from
each other, but anteriorly they
converge so as to approach the
two vasa deferentia, which run
forwards to the prostate between
them. With the vasa deferentia
thus interposed, they occupy the
two diverging sides of the tri-
angular portion of the base of
the bladder, which lies upon the
rectum, and is bounded behind
by the line of reflexion of the
peritoneum at the extremity of
the recto- vesical pouch. The

seminal vesicles themselves also rest upon the rectum, but are separated from it by a
layer of the recto- vesical fascia, which attaches them to the base of the bladder.

The sacculated appearance of the seminal vesicles is owing to their peculiar
formation. Each consists of. a tube somewhat coiled and repeatedly doubled on
itself, and invested by dense fibrous tissue. When unrolled, this tube is found to
be from four to six inches long, and about the width of a quill. Its upper
extremity is closed, so that it forms a long cul-de-sac ; but there are generally, if


not always, several longer or shorter branches or diverticula connected with it, which
also end by closed extremities (fig. 249). Inferiorly the seminal vesicle becomes
straight and narrowed, and ends opposite the base of the prostate by uniting on its
inner side, at an acute angle, with the narrow termination of the corresponding vas
deferens to form a single canal, which is the common seminal or ejaculatory duct.

The vesiculse seminales receive branches from the inferior vesical and middle
hamorrhoidal arteries and veins. The nerves belong to the sympathetic system, and
come from the hypogastric plexus.

In structure, the seminal vesicles resemble very closely the adjoining sacculated
portions of the vasa deferentia. Besides an external investment, connected with the
recto-vesical fascia, and containing vessels of considerable size, lymphatics, and
gangliated nervous cords, they have a muscular coat and a mucous membrane. The
muscular layers are thin compared with those of the vas deferens, and consist
of two layers, an outer of longitudinal, and an inner of circular fibres. A
considerable amount of plain muscular tissue is found covering the posterior
surface and extending transversely between the two vesicles. There are also longi-
tudinal fibres traceable over the vesicles from those of the bladder (Ellis, Henle).
The mucous membrane is traversed by very many fine rugge, which form an alveolar
structure resembling that seen in the gall-bladder, but deeper and enclosing much
finer meshes. The epithelium of the vesicles is columnar with a deeper layer of
small polyhedral cells.

The ducts of the testis serve as receptacles or reservoirs for the semen, as is proved by a
microscopic examination of their contents ; but. this is not usually the case with the seminal
vesicles : it is probable that they secrete a peculiar fluid which is incorporated with the semen.

The common seminal or ejaculatory ducts, two in number (fig. 249, E.D.),
are formed on each side by the junction of the narrowed extremities of the corre-
sponding vas deferens and vesicula seminalis, close to the base of the prostate gland.
From this point they run forwards and downwards, at the same time approaching
each other, and then pass side by side through the prostate between its middle and
two lateral lobes. After a course of nearly an inch, during which they become
gradually narrower, they end in the floor of the prostatic portion of the urethra by
two small slit-like orifices placed on the verumontanum, one on each prominent
margin of the opening of the prostatic utricle (fig. 261, d). For a short distance
the ejaculatory ducts run in the substance of the walls of the utricle.

The coats of the common seminal duct, as compared with those of the vas
deferens and vesicula, are very thin. The muscular coat consists of an outer thin
circular and an inner longitudinal layer, the outer longitudinal fibres becoming
blended with the muscular tissue of the prostate. The strong areolar tunic almost
entirely disappears after the entrance of the ducts between the lobes of the prostate,
but muscular fibres may be traced into the prostatic portion. The mucous membrane
becomes gradually smoother as it passes into that of the urethra. Its epithelium is
like that in the seminal vesicles and vas deferens. According to Henle, the
muscular fibres of the duct as it passes through the prostate are separated from one
another by blood-vessels, and form the trabeculse of a layer of cavernous tissue.

These ejaculatory ducts convey the fluid contained in the seminal vesicles and
vasa deferentia into the urethra. Their canal gradually narrows as they approach
their termination, where the diameter is reduced to 0'5 mm.

Vessels and nerves of the testis. The testicle and its excretory apparatus
receive blood-vessels and nerves from sources which are different from those giving
the vascular and nervous supply to the coverings of those parts.

Arteries. The spermatic artery, or proper artery of the testicle, is a slender and
remarkably long branch, which arises from the abdominal aorta, and passing down


the posterior abdominal wall reaches the spermatic cord, and 'descends along it to
the gland. In early foetal life its course is much shorter, as the testis is then situated
near the part of the aorta from which the artery arises. As the vessel approaches :
the testicle, it gives off small branches to the epididymis, and then divides into others
which perforate the tunica albuginea at the back of the gland, and pass through the
corpus Highmori ; some spread out on the internal surface of the tunica albuginea,
whilst others run between the lobes of the testis, supported by the fibrous processes
of the mediastinum. The smallest branches ramify on the delicate membranous
septa between the lobes, before supplying the seminiferous tubes.

The vas deferens receives from one of the vesical arteries a long slender branch
which accompanies the duct, and hence is named the artery of the vas deferens. It
ramifies in the coats of the duct, and reaches as far as the testis, where it anasto-
moses with the spermatic artery.

Veins. The spermatic veins commence in the testis and epididymis, passing out
at the posterior border, where they unite into larger vessels, which freely communi-
cate with each other as they ascend along the cord, and form the pampiniform plexiis.
Ultimately two or three veins follow the course of the spermatic artery into the
abdomen, where they unite into a single trunk {spermatic vein), that of the right
side opening into the inferior vena cava, and that of the left into the left renal vein.

Lymphatics. The lymphatics accompany the spermatic vessels and terminate
in the lumbar lymphatic glands, which encircle the large blood-vessels in front of the
vertebral column. As previously stated, they begin from intercommunicating lymph
spaces which occupy the intervals between the tubuli seminiferi.

Nerves. The nerves are derived from the sympathetic system. The spermatic
plexus is a very delicate set of nervous filaments, which descend upon the spermatic
artery from the renal and aortic plexuses. <Some additional filaments, which are
very minute, come from the hypogastric plexus, and accompany the artery of the
vas deferens.


The penis is composed principally of erectile tissue, arranged in three long
somewhat cylindrical masses, which are enclosed in fibrous sheaths, and are united
together so as to form a three-sided prism which receives a covering from the
general integument. Of these masses, two, named corpora cavernosa penis, placed
side by side, form the principal part of the organ, whilst the other, situated beneath
the two preceding, surrounds the canal of the urethra, and is named corpus
cavernosum urethra, or corpus spongiosum.

The penis is attached at its root to the symphysis of the pubes, and to the pubic
arch ; in front it ends in an enlargement named the glans, which is structurally
similar to and continuous with the corpus spongiosum. The intermediate portion or
body of the penis, owing to the manner in which its three component parts are
united together, has three somewhat flattened and grooved sides and three rounded
borders : the upper side is named the dorsum. The glans penis, which is slightly
compressed above and below, has at its extremity a vertical fissure forming the
external orifice of the urethra (meatus urinarius) ; its base, which is wider than the
body of the penis, is hollowed out to receive the narrowing extremities of the
corpora cavernosa ; its border is rounded and projecting, and is named the corona
ylandis, behind which is a constriction of the penis named the cervix. The median
fold of integument connecting the glans below the urethral orifice to the inferior
border of the penis is named the/ram/,w of the prepuce.

The integument of the penis, which is continued from that of the pubes and
scrotum, forms a simple investment as far as the neck of the glans. Here it
is doubled up in a loose fold, the prepuce or fore-skin. The inner layer of this fold



is firmly attached behind the cervix ; and from thence the integument, becoming
closely adherent, is continued forwards over the corona and glans, as far as the
orifice of the urethra, where it meets with the mucous membrane "of ~the urethra.


c.c., corpus^cavernosum ; s, corpus spongiosum ; B, its bulb ; G, part forming the glans penis. Foi-
the other lettering, seep. 114.



Upon the body of the penis the skin is thin, free from fat, and, in the anterior
two-thirds of its length, from hairs also ; in these respects differing remarkably from


NEUM. (J.S. ) {.

P.S., pubic symphysis ; i.R. , inferior
ramus of pubis (the ramus of the ischium
and the ischial tuberosity are posterior
to the plane of this section) ; C.P. , cms
penis ; B, bulb of corpus spongiosum ;
i.e. ,ischio-cavernosus muscle ; B.C., bulbo-
cavernosus muscle ; P.V., superficial peri-
neal vessels and nerves ; s. of P., skin
of perineum ; D.V., dorsal vein of penis
with an artery and a uerve on each side.

that on the pubes, which is thick,
covers a large cushion of fat, and,
after puberty, is beset with hairs :
the skin of the penis is moreover
very movable and distensible, and
is of a darker colour than the skin
generally. At the free margin
of the prepuce the integument
changes its character, and ap-
proaches that of a mucous mem-
brane, being red, thin, and moist.
Numerous sebaceous glands are
collected round the cervix of the penis and corona glandis ; they are named the
glands of Tyson, or glandules otlorifercn, their secretion having a peculiar odour.

Upon the surface of the glans the integument again changes its character ;

THE PUBES AND ISCHIUM (from Kobelt). f.

a, a, ejaculator urinae muscle covering the bulb of
the spongy body of the iirethra, with at e, poste-
riorly, a median notch ; b, b, anterior slips of the bulbo-
cavcrnosus muscle passing round the sides of the corpora
cavernosa ; c, c, crura of the penis, with an oval dila-
tation or bulb of the corpus cavernosum; d, d, ischio-
cavernosi or evectores penis muscles ; /, corpus spongiosum

it contains no glands, but is beset with large
vascular and nervous papillae, and it adheres
most intimately and immovably to the spongy
tissue of the glans.

Online LibraryJones QuainQuain's Elements of anatomy (Volume 3:4) → online text (page 29 of 44)