STKUCTURE OF PROSTATE. 521 



boundary, so as to detach the crus of the penis from the bone, and the 

 end of the rectum from the parts around. When the viscera are removed, 

 the rectum is to be separated from the other organs ; but the bladder, the 

 penis, and the urethra are to remain united. 



After the bladder has been distended with air, the areolar tissue is to 

 be removed from the muscular fibres. The prostate gland and the vesiculse 

 seminales are to be then cleaned ; and the duct of the latter, with the vas 

 deferens, is to be followed to the gland. 



If any of the integument has been left on the penis and the urethra it is 

 to be taken away. 



THE PROSTATE GLAND AND SEMINAL VESICLES. 



PROSTATE GLAND (fig. 178). This is a firm muscular body, with glands 

 in it secreting a special fluid, which surrounds the neck of the bladder 

 and the beginning of the urethra. Its connections with parts around 

 have been enumerated (p. 507). 



The prostate is conical in form like a chestnut, with the base or larger 

 end directed backwards. Its dimensions in different directions are the 

 following : Transversely at the base it measures about an inch and a half; 

 from apex to base an inch and a quarter; and in depth about three-quarters 

 of an inch or an inch : so that an incision directed obliquely outwards and 

 backwards laterally, from the apex to the base, will be the longest that 

 can be practised in the half of this body. Its weight is about an ounce, 

 but in this respect it varies greatly. 



The upper surface of the prostate is narrow and rounded. The under 

 surface, which is larger and flatter, is marked by a median hollow which 

 indicates the division into lateral lobes. 



The posterior part, or the base, is thick, and in its centre is a notch 

 which receives the common seminal ducts. The forepart or apex is 

 pierced by the urethra. 



Three lobes are described in the prostate, viz., a middle and two lateral, 

 though there is no fissure in the firm mass. The lateral parts or lobes 

 (fig. 178, ft, c) are similar on both sides, and are separated only by the 

 hollow on the under surface ; they form the chief part of the prostate, 

 and are prolonged back, on each side, beyond the notch in the base. The 

 middle lobe (rf) will be brought into view by detaching the vesiculae semi- 

 nales and the vasa deferentia from the bladder ; it is the piece of the gland 

 between the neck of the bladder and the seminal ducts, which extends 

 across between the lateral lobes. Oftentimes the middle lobe is enlarged 

 in old people, and projects upwards into the bladder, so as to interfere 

 with the flow of the urine from that viscus, or the passage of a catheter 

 into it. 



The urethra and the two common seminal ducts are contained in the 

 substance of the prostate (fig. 180). The former is transmitted through 

 the gland from base to apex ; and the latter perforate it obliquely to ter- 

 minate in the urethral canal. 



Structure. On a section the gland appears reddish gray in color, is 

 very firm to the feel, and is scarcely lacerable. It is made up of a mass 

 of unstriated muscular and fibrous tissues, with interspersed glandular 

 structure ; and the whole is enveloped by a fibrous coat. 



Fibrous covering. This forms a thin investment for the gland, and 

 sends offsets into the interior. It is quite distinct from the denser sheath 



