PROSTATE GLAND. 



153 



With these facts before us, there is no ne- 

 cessity to resort to the mechanical idea of 

 the gradual distension of the prostate gland 

 and vesiculae seminales to account for the 

 existence of a rudimentary uterus in those 

 cases of hermaphrodism where the subject is 

 unquestionably male, with an increase in the 

 development of the utriculus beyond its na- 

 tural condition. I would also venture to 

 suggest, that what Mr. Hunter has delineated 

 as the uterus, in the representation he has 

 given of the dissection " of Mr. Wright's free- 

 martin, which are more the parts of a bull 

 than those of a cow," is really a preter- 

 naturally large utriculus prostaticus. I have 

 given a side view of the interior of the utricu- 

 lus, in a case which I examined myself ; in 

 this instance it extended obliquely down- 

 wards and backwards, beneath the third lobe 

 of the prostate, for the distance of about half 

 an inch, and was slightly enlarged at its 

 fundus. (See Jig. 104.) 



The development of the prostate and vesicula 

 prostatica. There is no department of em- 

 bryological research of higher interest than 

 that relating to the development of the 

 genito-urinary system. A minute inquiry into 

 this subject, and a careful observation of the 

 phenomena attending it, can afford the only 

 means of obtaining a satisfactory clue to the 

 comprehension of that remarkable structure 

 just described. By no other means is it pos- 

 sible to ascertain the natural relation of the 

 utriculus prostaticus. 



I shall limit the inquiry here to the manner 

 in which the utriculus and prostate gland are 

 supposed to be formed. 



At an early period of foetal existence the 

 allantoid sac, which was continuous with the 

 urinary bladder, becomes shut off entirely 

 from that viscus, and the only remains of its 

 original communication is the obliterated ura- 

 chus. As the bladder at its inferior fundus 

 communicates with the intestine, thus forming 

 with it one common cavity, it may fairly be said 

 that the human subject really is at this period 

 possessed of a cloaca. In the mammiferous 

 class generally the urinary bladder very soon 

 separates from the intestine, and has a sepa- 

 rate opening externally in front of the anal 

 aperture. There are different opinions as to 

 how this is actually accomplished ; but there 

 is no necessity to discuss the question here. 

 In this separation of the bladder from the 

 rectum, the evidence of the existence of a 

 cloaca disappears, and a cavity, or space, or 

 canal is left common to the bladder and geni- 

 tal organs ; this is termed the sinus uro-geni- 

 talis, or the canalis uro-genitalis. This after* 

 wards, in the male, is represented by the neck 

 of the bladder and beginning of the urethra, 

 and communicates with the external organs. 

 In the monotremata the uro-genital canal is 

 persistent. The sinus uro-genitalis receives 

 the terminations of the excretory ducts of the 

 Woolfian bodies, the ureters, the vasa defe- 

 rentia in the male, and the fallopian tubes in 

 the female. In the female the vagina and 

 uterus are both developed by extension and 



division of this canal, the vagina having in 

 front of it the urethra ; and as development 

 advances, the last portion of the sinus uro-geni- 

 talis is represented by the vestibulum, and is 

 common to the urethra and the vagina. Ac- 

 cording to Valentin, in the male the vasa defe- 

 rentia at first open together in the mesial por- 

 tion of the uro-genital canal ; in the female the 

 same is observed in respect to the fallopian 

 tubes. Rathke states that at a later period 

 a small conical crimpling of the uro-genital 

 sinus occurs near the openings of the vasa 

 deferentia, and that from this the vesiculae 

 seminales are developed, which communicate 

 with the vasa deferentia, and, indirectly, with 

 the sinus, or with the urethra itself. A se- 

 paration takes place between the two vasa 

 deferentia, when each vas deferens, uniting 

 with a corresponding vesicule, opens sepa- 

 rately into the urethra. In the interval be- 

 tween the terminations of the vasa deferentia 

 we find the remains of the uro-genital sinus, 

 which eventually becomes the utriculus, or ve- 

 sicula prostatica, or sinus pocularis. 



Bischoff thinks that the prostate gland com- 

 mences by a simple thickening of the vasa 

 deferentia near their termination. It is most 

 probably further developed in the same man- 

 ner as the glandular system generally. He 

 agrees with Rathke in the opinion that there 

 exists a septum between the two sides at this 

 portion of the urethra, the vestiges of which 

 are represented by the veru montanum. 



To complete the analogy between the utri- 

 culus and the female uterus, the vasa ejacu- 

 latoria ought to terminate beneath, or rather 

 within the utriculus, as the fallopian tubes do 

 in the uterus ; and this is said really to hap- 

 pen occasionally. Morgagni mentions two 

 instances of this. I have found it myself, but 

 it is rare ; yet the fact of even its occurrence 

 now and then adds all we require to complete 

 the evidence in favour of the analogy between 

 these two apparently dissimilar structures. 

 Presuming all that has been stated to be true, 

 we need not tax our ingenuity further, in en- 

 deavouring to assign a use to this heretofore 

 obscure structure the sinus pocularis. 



The prostate, up to the period of the full 

 development of the organs of generation, is 

 of small size. In the early periods of foetal 

 existence it is composed of two lateral lobes, 

 which coalescing at the fourth or fifth 

 month, give rise to the isthmus and third 

 lobe.* It is rounder in the child, is situated 

 vertically, and is said to be occasionally just 

 reached by the peritonaeum. As we advance 

 in life it becomes firmer in texture and yel- 

 lowish in colour. Mercier says that in the 

 child the anterior part of the gland exceeds 

 the posterior in thickness; in other words, 

 that the prostatic ring encircling the urethra 

 is thicker above than below. 



Function of the prostrate gland. It is the 

 office of the prostate to secrete a bland and 



* I do not consider the isthmus and third lobe as 

 synonymous expressions, and would limit the former 

 term to that portion of the gland which connects 

 the lateral lobes beneath the urethra. 



