THE URETHRA. 179 



In Front, the urethral opening. 



Posteriorly, a line connecting the orifices 3 of the ureters. 

 Laterally, two ridges of mucous membrane, which extend from the ure- 

 thral orifice back to the orifices of the ureters. 



What is the Uvula Vesicae ? ( 4 , Fig. 89.) A small elevation of mu- 

 cous membrane projecting from the floor of the bladder into the urethral orifice. 

 It is said to be lifted by the anterior fibres of the levator ani muscle. 



Describe the Structure of the Bladder. It has a partial peritoneal in- 

 vestment, and its walls are composed of 3 coats, a muscular, a cellular, and 

 a mucous. The 



Muscular Coat, consists of 5 sets of fibres, as follows, 

 External and Internal Longitudinal fibres. 

 Intermediate Circular fibres, forming a Sphincter Vesicce at the neck of 



the bladder. 



Transverse fibres, connecting the orifices of the ureters. 

 Muscles of the Ureters, connecting their orifices with the middle lobe of 



the prostate gland. 

 Cellular Coat, connects the other two coats together, and is closely attached 



to the mucous coat. 



Mucous Coat, is covered with epithelium intermediate in form between the 

 columnar and the squamous ; is loosely connected to the muscular coat, 

 except at the trigone vesicale and the uvula vesicas, where it is closely 

 adherent. 



What Nerves supply the Bladder ? Branches from the hypogastric 

 plexus supply its upper part, from the sacral plexus its base and neck. 



THE MALE URETHRA. 



What is the Urethra ? It is the urinary canal from the neck of the 

 bladder to the meatus urinarius ; in the male it is chiefly within the penis, and 

 from 8 to 9 inches in length. 



Enumerate its Divisions. The male urethra is divided into 3 parts, 

 the prostatic, membranous and spongy. 



Describe the Prostatic portion of the Urethra. 14 It is that part of 

 the canal which pierces the prostate gland, 12 is about i^ inch in length, of 

 spindle-shape, and is the widest and most dilatable part of the urethra. Its 

 floor presents the 



Veru Montanum, or Caput Gallinaginis,* an elevation of the mucous 

 membrane and its adjacent tissue, ^ inch long, and supposed to contain 

 muscular and erectile tissue. 



