CONNECTIONS OF BLADDER. 507 



The ureter (fig. 174, fi) crosses the common or the external iliac artery, 

 and forms an arch below the level of the obliterated hypogastric vessel ; it 

 enters the bladder near the lower part, and somewhat on the side, at the 

 distance of one inch arid a half or two inches from the prostate gland. 



The PROSTATE GLAND (fig. 174, 6) surrounds the neck of the bladder. 

 It is placed about an inch below the level of the symphysis pubis, and is 

 supported by the rectum. Its shape is conical with the base turned back- 

 wards, and its size equals nearly that of a large chestnut. In the present 

 position of the pelvis, a line from the apex through the middle of the gland 

 would be directed obliquely downwards and backwards towards the end of 

 the sacrum ; but in the erect state of the body, upwards and backwards 

 from the triangular ligament. 



The upper surface is about an inch below the symphysis pubis, and is 

 connected to it by the anterior true ligaments of the bladder. On this 

 surface are branches of the dorsal vein of the penis. 



The under surface has the greatest extent, and is contiguous to the 

 rectum ; this is the part that is felt by the finger introduced into the bowel 

 through the anus. 



The apex touches the posterior layer of the triangular ligament ; and 

 the base surrounds the neck of the bladder, and the vesicular seminales 

 with the vasa deferentia. 



The prostate is enveloped by a sheath obtained from the recto-vesical 

 fascia (p. 502), and a plexus of veins (prostatic) surrounds it. Through 

 the gland the urethra takes its course to the penis ; and the ejaculatory 

 ducts pierce it obliquely to open into the urethra (fig. 180,/). The size 

 of the prostate alters much, and in old men it may acquire a considerable 

 magnitude. 



The VESICULJE SEMIXALES (fig. 174, g} are two small sacculated bodies, 

 each about two inches long, between the under part of the bladder and 

 the rectum. Each is pyramidal in form, and has the larger end turned 

 backwards towards the ureter, whilst the smaller is surrounded by the 

 prostate. Along the inner side is the vas deferens. At the prostate gland 

 the vesiculiB approach one another, only the vasa deferentia intervening ; 

 but further backwards they diverge, and inclose with the pouch of the 

 peritoneum the triangular space at the under aspect of the bladder. The 

 vesiculiB are contained in a membranous sheath, which is derived from 

 the recto-vesical fascia, and is lined by involuntary muscular fibres. 



The VAS DEFEUENS or the excretory duct of the testis (fig. 174,/) in 

 its course to the urethra enters the abdomen by the internal abdominal 

 ring; and crossing the obliterated hypogastric artery, is directed inwards 

 along the side and under part of the bladder to the base of the prostate, 

 where it forms the common ejaculatory duct by joining with the duct 

 from the vesicula seminalis. The position of this tube to the external 

 iliac artery has been noticed ; on the bladder it passes internal to the 

 ureter and the vesicula of the same side. By the side of the vesicula the 

 duct is much enlarged, and is sacculated. 



The URETHRA is the excretory passage for the urine and semen (fig. 

 174), and reaches from the bladder to the end of the penis. In length it 

 measures about eight inches, and it presents one or two curves according 

 to the state of the penis. At first the canal is directed forwards through 

 the triangular ligament of the perinaeum to the body of the penis, forming 

 a large curve with the concavity to the pubes. Thence to its termination 

 the urethra is applied to the penis ; and whilst this body remains pendent 



