Male Generative Organs. 



PROSTATE GLAND. 



THE Prostate Gland (itpo'iottjfu, to stand before) is a pale, firm, glandular body, 

 which surrounds the neck of the bladder and commencement of the urethra. It 

 is placed in the pelvic cavity, behind and below the symphysis pubis, posterior 

 to the deep perineal fascia, and upon the rectum, through which it may be distinctly 

 felt, especially when enlarged. In shape and size it resembles a horse-chestnut. 



Its base is directed backwards towards the neck of the bladder. 



The apex is directed forwards to the deep perineal fascia, which it touches. 



Its under surface is smooth, and rests on the rectum, to which it is connected 

 by a dense areolar fibrous tissue. 



Its upper surface is flattened, marked by a slight longitudinal furrow, and placed 

 about three-quarters of an inch below the pubic symphysis. 



It measures about an inch and a half in its transverse diameter at the base, an 

 inch in its antero-posterior diameter, and three-quarters of an inch in depth; 

 and its weight is about six drachms. It is held in its position by the anterior 

 ligaments of the bladder (pubo-prostatic) ; by the posterior layer of the deep 

 perineal fascia, which invests the commencement of the membranous portion of 

 the urethra and prostate gland ; and by the anterior portion of the Levator ani 

 muscle (levator prostatse), which passes down on each side from the symphysis pubis 

 and anterior ligament of the bladder to the sides of the prostate. 



The prostate consists of three lobes ; two lateral and a middle lobe. 



The two lateral lobes are of equal size, separated behind by a deep notch, and 

 marked by a slight furrow upon their upper and lower surface, which indicates 

 the bi-lobed condition of the organ in some animals. 



The third or middle lobe is a small, transverse band, occasionally a rounded or 

 triangular prominence, placed between the two lateral lobes at the under and 

 posterior part of the organ. It lies immediately beneath the neck of the bladder, 

 behind the commencement of the urethra, and above the ejaculatory ducts. Its 

 existence is not constant, but it is occasionally found at an early period of life, as 

 well as in adults, and in old age. In advanced life it often becomes considerably 

 enlarged, and projects into the bladder, so as to impede the evacuation of the urine. 



The prostate gland is perforated by the urethra and common seminal ducts. 

 The urethra usually lies about one-third nearer its upper than its lower surface ; 

 occasionally, the prostate surrounds only the lower three-fourths of this tube, and 

 it more rarely runs through the lower than the upper part of the gland. The 

 ejaculatory ducts pass forwards obliquely through a conical canal, situated in the 

 lower part of the prostate, and open into the prostatic portion of the urethra. 



Structure. The prostate is inclosed in a thin but firm fibrous capsule, distinct 

 from that derived from the posterior layer of the deep perineal fascia, and sepa- 

 rated from it by a plexus of veins. Its substance is of a pale, reddish-gray color, 

 very friable, but of great density. It consists of glandular substance and muscular 

 tissue. 



The glandular substance is composed of numerous follicular pouches, opening 

 into elongated canals, which join to form from twelve to twenty small excretory 

 ducts. The follicles are connected together by areolar tissue, supported by pro- 

 longations from the fibrous capsule, and inclosed in a delicate capillary plexus. 

 The epithelium lining the canals is columnar, whilst that in the terminal vesicles 

 is of the squamous variety. 



The muscular tissue of the prostate is arranged in the form of circular bands 



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