80 URINARY ORGANS. 



strictures and other obstructions of the urethra. These fasci- 

 culi, for the most part, arise about the neck of the bladder, and 

 ascending upwards, before, behind, and laterally, terminate at 

 the superior fundus in the base of the urachus. Within these, 

 which may be considered as the longitudinal fibres of the blad- 

 der, there are others forming a thinner lamina, whose course is 

 transverse, or oblique : they serve to connect the preceding. 

 As the muscular fibres are collected at the neck of the bladder, 

 and at the urachus, there is, of course, an increased thickness 

 at these points. 



The Cellular Coat consists in a close, dense, lamellated, and 

 filamentous tissue, very extensible and difficult to tear. It is 

 impervious to water, adheres closely to the muscular coat with- 

 out, and to the mucous within, so as to form a strong bond of 

 union between them. It is pervaded by many vessels and 

 nerves, which it conveys to the mucous coat. 



The Mucous Coat is also called the villous, but is much more 

 smooth than the corresponding one of the stomach. It is while, 

 with a slight tinge of red, and abounds with mucous follicles, 

 which, though small and scarcely discernible in a natural state, 

 are rendered very obvious by disease. It stretches with much 

 facility, but, like other mucous membranes, does not restore 

 itself readily, and is rather thrown, in the contracted state of 

 the bladder, into wrinkles or folds, having a diversified course, 

 and of a fugitive character, as they disappear again upon the 

 next distention. It is very vascular. 



The internal face of this coat presents, at its inferior part, 

 the following appearances: 



1. The Vesical Triangle (Trigonus Lieutaudi, Trigone Ve- 

 sicale) is placed immediately behind and below the neck of the 

 bladder, occupying the space between it and the orifices of the 

 ureters. It is an equilateral triangle of an inch in length, its 

 surface is smooth, is not affected materially in extent either by 

 the dilatation or the contraction of the bladder, and is elevated 

 go as to be sufficiently distinct and well defined. 



2, The anterior angle of the triangle looks into the orifice of 

 the urethra, and is generally so elevated that it has obtained 

 ihe name of Uvula Vesicle; it is, however, simply a projection 



