506 BLADDER. [CHAP. XXXIV . 



owing to the arrangement of the muscular fasciculi. The mucous 

 membrane is sometimes forced through the small spaces between 

 the fibres, and thus a number of sacculi are produced, a condition 

 termed sacculated bladder. 



At the lower part of the bladder is a perfectly smooth and pale 

 surface, of the form of an equilateral triangle, the apex of which 

 points towards the prostate. The ureters open one at each of 

 the posterior angles; and between them there is a prominent 

 line caused by the mucous membrane being somewhat raised in 

 this situation. This triangular portion of the floor of the bladder 

 is called the trig one (triangle), and the mucous membrane is 

 attached more firmly than in other parts to the muscular coat 

 beneath, whence its smooth character. The bladder is only par- 

 tially covered with peritoneum. It is connected in the male with 

 the rectum, and in the female with the uterus and upper part of 

 the vagina by much loose areolar tissue, which permits great 

 freedom of movement of these parts upon one another. 



The bladder is kept in its position by certain reflexions of peri- 

 toneum passing over bands of white fibrous tissue, or reflexions of 

 the vesical fascia (true ligaments), and by folds of peritoneum alone 

 (false ligaments). 



The anterior reflexions of the vesical fascia constitute the ante- 

 rior true ligaments of the bladder. These arise from the lower mar- 

 gin of the pubis on each side of the symphysis. They then pass 

 over the upper surface of the bladder. Many of these fibres are 

 attached to the muscular fibres, and this ligament may be said to 

 serve as the tendon of attachment of many of the fibres which 

 constitute the detrusor urinse muscle. 



The fundus of the bladder is connected with the umbilicus by 

 the suspensory ligament of the bladder, a reflexion of peritoneum 

 which encloses the obliterated hypogastric arteries and urachus. 



The muscular coat of the bladder is composed entirely of un- 

 striped fibre-cells, which are much interwoven, but may be des- 

 cribed as arranged in two layers, an external longitudinal, and an 

 internal transverse or circular. 



The latter are exceedingly numerous round the neck of the 

 bladder, whence they have received the name of Sphincter Vesicae. 



The longitudinal fibres are most abundant upon the anterior 

 and posterior surfaces of the bladder, and constitute the detrusor 

 urinoe muscle. 



The mucous membrane is of a pale colour, and is loosely con- 

 nected to the muscular tissue by the intervention of much loose 



