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basal surface of the contracted and empty bladder receives a covering from the peritoneum, since the seminal vesicles and terminal portions of the ductus deferentes intervene as they lie in the anterior wall of the recto-vesical or rectogenital pouch. When the bladder is distended the posterior border, separating the upper and basal surfaces, is rounded out, and the peritoneum forming the horizontal shelf, just described, is taken up (compare Figs. 989 and 990). It is

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Dorsal vein of penis Corpus cavernosum penis.Corpus cavernosum

urethree

Anal canal

Membranous urethra
Cavernons portion of urethra Bulb of urethra

Fig. 1001.-MEDIAN SECTION OF THE PELVIS IN AN ADULT MALE.
The coils of small intestine which lay within the pelvis have been lifted out in order to give a view of

wall of the pelvic cavity.

the side

to be specially noted that the level of the peritoneal reflection, forming the bottom prostate, during distension and contraction of the bladder (Figs. 989 and 990). of the recto-vesical pouch, does not vary much, as regards its relationship to the of the ductus deferentes in any operation for reaching the bladder through the anterior vallo

An examination of median sections of the pelvis shows the great danger run by the am pulla the rectum, and the difficulty in avoiding injury to the peritoneum.

The term "posterior false (or peritoneal) ligament” is often applied to the som what variable crescentic fold of peritoneum which bounds, on each side, the entrance to the recto-vesical or recto-genital pouch, and which often unites

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the opposite side across the median plane, behind the posterior border of rand the ductus deferentes. These folds represent the plicæ rectouterinæ Douglas in the female, and are to be regarded as connexions of the ductus rather than of the bladder; hence the term sacro-genital folds is applicable ructures in both sexes. The folds are seen in Figs. 990 and 995. itoneum covering the upper surface of the empty or partly distended bladder its a transversely disposed fold or wrinkle, to which the term plica vesicalis has been applied. This fold, when well developed, can be traced on to the f the pelvis, where it traverses the paravesical fossa, and in some cases it is ross the pelvic brim and to be directed towards the abdominal inguinal ring

female the peritoneum is reflected posteriorly from the upper surface of r on to the anterior aspect of the uterus. on of the Bladder.—When the ligamentum umbilicale medium, or fibrous e urachus, which binds the bladder apex to the anterior abdominal wall, eritoneal folds, already described as the false ligaments, are severed, the easily moved about, except in its lower and basal parts. Anteriorly it ed to the pubis, and laterally to the fascial lining of the pelvis by loose sue only, which permits free movement during expansion and contraction. - fixed part of the bladder is held in place chiefly by processes of the cia, continuous with those forming the sheath of the prostate. The nexions constitute the true ligaments of the bladder, and are described ostatic or anterior ligaments, reaching the bladder from the pubis in front, I ligaments, reaching the bladder from the fascial lining of the side wall tis. ition to the urachus and the peritoneal and the true ligaments already 1, the bladder is supported and fixed in position, in the region of its ce, by the dense fibrous and unstriped muscular tissue which surrounds al vesicles, the terminal portions of the ductus deferentes and the ureters. y the strands of connective tissue and the bundles of muscle fibres forming this supackwards and are continued into the fascia which surrounds the branches of the

artery. Muscle fibres connected with the bladder wall are also found within the tic ligaments, through which they are attached to the pubis. female the basal part of the bladder wall is supported and held in place nexion with the anterior wall of the vagina. The region of the urethral he most firmly fixed part of the bladder wall in both sexes. cure of the Bladder Wall.--The wall of the bladder from without inwards d of a serous, a muscular, a submucous, and a mucous coat. The tunica serosa coat, formed by peritoneum, is incomplete, and covers only the upper and arts of the distended bladder (Fig. 993). iderable amount of fibrous connective tissue surrounds the tunica muscularis ar coat, and penetrating it, divides it into numerous coarse bundles of muscle 1 the muscle fibres are of the unstriped variety, and the bundles which they arranged in three very imperfectly separated strata called external, middle, al. The stratum externum is for the most part made up of fibres which are ngitudinally, and it is best marked near the median plane on the upper and under the bladder. Farther from the median plane, on the sides of the bladder, the posing the external stratum run more obliquely, and their directions frequently nother. In the male, many of the fibres of the external stratum are attached iorly and posteriorly to the prostate, and in the female the corresponding fibres ense tissue which in this sex forms the upper part of the wall of the urethra. es of this stratum on each side of the body join the lower part of the symphysis

constitute the musculus pubovesicalis, which lies in the substance of puboigament. Lastly some fibres of the external stratum blend posteriorly with the spect of the rectum and receive the name of musculus rectovesicalis. nedium is composed of fibres which for the most part run circularly, and greater part of the thickness of the muscular coat. In the region of, and

The behind, the urethral orifice the bundles of fibres are finer and more densely arrangeri, and surround the opening in a plane which is directed obliquely downwards and forwards This part of the middle stratum is often spoken of as the “sphincter vesicæ.” Inferiorly the fibres of the sphincter vesicæ are continuous with the muscular tissue of the prostate in the male, and with the muscular wall of the urethra in the female. In other parts of the bladder the bundles of the middle stratum are coarser and separated by intervals filled with connective tissue. The stratum internum is a thin layer of fibres directed for the most part longitudinally.

The tela submucosa or submucous coat is composed of areolar tissue, but contains numerous fine elastic fibres.

The tunica mucosa or mucous coat is loosely attached, by means of the submucous layer, to the subjacent muscular coat, except in the region of the trigonum vesicæ, where the muscular fibres lie close beneath, and are firmly adherent to the mucous membrane. Over the trigonum the mucous coat is always smooth and flat; elsewhere it is thrown into folds when the bladder is empty. The mucous membrane of the bladder is continuous with that of the ureters and urethra. The epithelium, covering it, raries much in appearance in different conditions of the organ, and is of the variety known as transitional stratified epithelium. The appearance of the mucous coat is described on p. 1277.

Vessels and Nerves of the Bladder. The bladder receives its blood supply on each side from the superior and inferior vesical arteries. The inferior vesical artery arises from the hypogastric artery, and the superior vesical arises from the umbilical artery just before it becomes obliterated. The largest veins are found just above the prostate, and in the region where the ureter reaches the bladder. They form a dense plexus which pours its blood into tributaries of the hypogastric vein, and communicates below with the pudendal venous plexus.

The lymph-vessels from the bladder join the iliac group of lymph-glands.

The nerve supply of the bladder is derived on each side from the vesical plexus, the fibres of which come from two sources, namely (1) from the upper lumbar nerves through the hypoga-tri: plexus, and (2) from the third and fourth sacral nerves. The fibres from the latter sources join the vesical plexus directly.

THE URETHRA.

The urethra is the channel which serves to convey the urine from the bladder to the exterior. In the male it consists of two portions, a proximal part, less than one inch in length, extending from the bladder to the points where the ducts of the reproductive glands join the canal, and a much longer distal portion which serves as a common passage for the secretion of the kidneys and for the generative products. An account of the male urethra follows the description of the male reproductive glands and passages (see p. 1304). In the female the urethra is more simple in its arrangement, and represents only the proximal part of the male canal. It is a short passage leading from the bladder to the external urethral orifice-an aperture placed within the rima pudendi or urino-genital cleft, immediately above and in front of the opening of the vagina.

Urethra Muliebris.—The female urethra is a canal of about one to one and a half inches in length which follows a slightly curved direction downwards and forwards, below and behind the lower border of the symphysis pubis. As it leaves the pelvis the urethra pierces the urogenital diaphragm and its faseir', and the part of the passage which lies between the superior and inferior layers of fascia is surrounded by the fibres of the sphincter urethræ membranacex muscle. Except during the passage of fluid the canal is closed by the apposition of its anterior and posterior walls. The orificium urethræ externum or external orifice is placed between the labia minora, immediately in front of the opening of the vagina, and lies about one inch below and behind the clitoris (Fig. 1002 The opening is slit-like, and is bounded by slightly marked lateral lips. The posterior wall of the urethra, except in its upper part, is very intimately connected with the anterior wall of the vagina. The mucous lining of the canal is raised into a number of slightly marked longitudinal folds, one of which, more distinct than the others, and placed upon the posterior wall of the passage, receives the name of crista urethralis.

ture.—The wall of the female urethra is thick and contains much fibrous ich passes without any sharp line of demarkation into the surrounding mass of e tissue. The tunica muscularis or muscular coat of the urethra is continuous h that of the bladder, and is composed of layers of circularly and longitudiposed smooth muscle fibres arranged to form outer and inner strata. Within llar coat the wall of the urethra is very vascular, and the canal itself is lined

mucous membrane which is thrown into longitudinally directed folds, one of he crista urethralis mentioned above. The epithelium of the canal, in its upper

the transitional variety, like that of the bladder ; in its lower part it becomes umerous minute glands, the glandulæ urethrales, and pit-like depressions

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02.—MEDIAN SECTION THROUGH THE FEMALE Pelvis. Drawn for the most part from a model

of a dissection by Professor Edward H. Taylor.

urethrales) open into the urethral canal. One group of these glands on each sses a minute common duct known as the ductus paraurethralis, which opens rima pudendi or urino-genital cleft by the side of the urethral orifice. It is that these latter glands represent the prostatic glands of the male subject. ular layer which lies between the muscular coat and the mucous membrane elastic fibres, and in appearance resembles erectile tissue. Striped muscle fibres mt on the outer aspect of the muscular coat of the urethra.

In the upper part nal these fibres form a complete ring-like sphincter, but in the middle and lower striped muscle fibres though present in front are absent on the posterior wall of ra, as at this level they pass backwards on the outer aspect of the vagina, and his latter passage together with the urethra in a single loop of muscle tissue. c fibres, therefore, form a urino-genital sphincter.

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attached to t

superior extre THE MALE REPRODUCTIVE ORGANS.

liquity of th

4 Duvre anterio We have here to describe (1) the testes or essential reproductive glands of the Epididymis male, together with their (2) coverings and (3) ducts, (4) the prostate, (5) the bulbo- cand the pos urethral glands, (6) the external genital organs, and (7) the male urethra.

ut of the The reproductive glands of the male, or testes, are a pair of nearly symmetrical epididymi oval-shaped bodies situated in the scrotum. The duct of each gland, at first of the tes much twisted and intertwined, forms a structure known as the epididymis, which

obective tis is applied against the posterior and lateral part of the testis. From the epic is termed didymis the excretory duct, or ductus deferens, passes upwards towards the inferior

by the se part of the anterior abdominal wall, which it pierces very obliquely, to enter the

body, OI abdominal cavity. Here each ductus deferens is covered by the peritoneum, and sterior paIE almost at once crossing the pelvic brim, enters the pelvis. The duct now runs on

T-ring of

th the side wall of the pelvis towards the base of the bladder, where it comes into siymidis relation with a branched tubular structure termed the vesicula seminalis. Joined

éiymidis (

OI by the duct of the vesicula seminalis, the ductus deferens forms a short canal called the ejaculatory duct, which terminates by opening into the prostatic part

Je ductus epi of the urethra. The prostate, a partly glandular, partly muscular structure, Minute ses surrounding the first part of the urethra, and also a pair of small glandular bodies called the bulbo-urethral glands, are accessory organs connected with the male

-- sidrunis and reproductive system. The ducts of the bulbo-urethral Cler's duct in glands and those of the prostate, like the ejaculatory ducts, open into the urethra, which thus serves not only as a passage for urine, but also for the ed is lined generative products. The ex- sables in an ternal genitals are the penis and peritoneus

scrotum. Spermatic

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THE TESTIS. Head of

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The Appendix

vaginalis glands, the testes, are a pair of scd The of testis

somewhat oval, slightly flat- 1:s traced
tened bodies of a whitish colour, zrel of the

measuring about an inch and a sticus or
Margo half in length, one inch from cards in EO

before backwards, and rather tha vagi na of testis

less in thickness. Each testis testis,
is placed within the cavity of serior wal?
the scrotum in such a manner

te the test
ihat its long axis is directed
upwards, slightly forwards, and mbrane 15
laterally, and usually the left e lamina
gland occupies a lower leveltibe tunica
than the right. The testising the
(Fig. 1003) has two somewhat led the lam

flattened surfaces, one of which, Tion. Betre Fig. 1003.-Right TESTIS AND EPIDIDYMIS, EXPOSED BY THE

called the facies lateralis, or REMOVAL OF THE ANTERIOR WALL OF THE SCROTUM. lateral surface, looks backwards as well as laterally; the other, the facies medialisymis, the or medial surface, looks forwards as well as medially, and is usually the more serial called t the margo anterior, is the more convex and free; while the other, the margo posterior. * from the te flattened. The two surfaces are separated by two rounded borders, one of which imited above

The as the superio is less rounded, and by it the organ is suspended within the scrotum. epididymis and the lowest portion of the funiculus spermaticus, or spermatic cord, artace of the

a covering

the testis

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