80 ESSAY ON TIIE DESCRIPTIVE ANATOMY OF THE 
The ureters are externally covered by a cellulo-muscular coat, 
consisting of a cellular tissue with muscular fibres arranged 
partly longitudinally and partly circularly, the latter being 
most internally situated. The ureters are internally lined by 
mucous membrane, continuous anteriorly with the renal pelvis, 
and posteriorly with the vesical lining. 
The membrane is loosely attached to the outer coat, and thrown 
into longitudinal effaceable folds. 
Bladder. 
The bladder is a dilatable musculo-membranous viscus, 
destined for the temporary retention of urine. It is situated 
during vacuity entirely within the pelvis, but when distended, 
even moderately, its fundus encroaches on the proper abdominal 
space. 
The bladder is held in situation by the peritoneum coming 
off from the rectum and sides of the pelvis, so as to form a 
serous fold, which also encloses the vasa deferentia and vesiculae 
seminales. Besides this, the bladder is supplied with true 
ligaments, as well as bounded posteriorly through the interven¬ 
tion of the urethra. 
The shape of the bladder is pyriform, approaching, however, 
to a sphere when empty or partially distended. 
It presents for consideration a projecting anterior portion 
or fundus, a middle part or body, and a posterior one, or 
neck. The fundus is globular and regular, having fixed at its 
anterior part the two obliterated umbilical arteries, and the 
remains of the urachus. The body has no precise limits, but 
may be considered as that portion on which the bulbous portions 
of the vasa deferentia rest. It is circular, but if the bladder be 
much distended, it bends somewhat backwards and upwards. 
The cervix vesicse is the most constricted part of the organ, and 
marks the limit between the bladder and urethra. 
The bladder is related by its fundus to the iliac flexures of 
the colon, inferiorly to the pubic and ischial bones, superiorly to 
the ureters, vasa deferentia, vesiculae seminales, and middle 
part of the rectum. 
The bladder has three coats. The peritoneal investment is 
merely a partial one, as it is reflected from the body on to the 
sides of the pelvis. It covers the superior surface almost 
completely, but its extent gradually declines laterally and in¬ 
feriorly. The attachments contracted by the peritoneum are 
termed false ones. Thus we have the two umbilical arteries, one 
on each side, enclosed by peritoneum, forming the two lateral false 
ligaments. Then the vestige of the urachus is similarly enve- 
