BLADDER, NORMAL ANATOMY. 383 



affecting the sac itself; hence a process of this rangement, although we are convinced that the 

 sort may enlarge indefinitely, and has been orifice is furnished with a sphincter such as we 

 known in some cases to have formed a part of shall presently describe. Moreover, we believe 

 the contents of an inguinal hernia. Pouches of that the prostatic secretion is more or less ex- 

 this nature, for there may be several in the pressed at each evacuation of the urine, inas- 

 same individual, sometimes contain calculi, the much as the longitudinal, the principal detrusor 

 latter having probably been the cause of the fibres of the bladder, are fixed into, expand 

 former, inasmuch as the muscular coat having upon, and must compress this gland, especially 

 been excited by the irritation of the stone to at the commencement of the process, although 

 increased action, has forcibly pressed the latter they obviously can have no effect on the vesi- 

 into one of the cells of the mucous membrane, culoe seminales, vasa deferentia, or their contents, 

 which has then become enlarged and protruded, The existence of a true muscular sphincter 

 so as to contain the calculus impacted in it. is denied by Sabatier, Anat. torn. ii. p. 403; 

 The consequence of this occurrence to the indi- Marjolin, torn. ii. p. 473; also by Bichat, 

 vidual, however, is often a fortunate remission Anat. desc. torn. v. p. 147; byBoyer, Anat. 

 of suffering, because the stone being now fixed torn. iv. p. 490; by Cloquet, Anat. torn. ii. p. 

 in a cell, ceases to excite pain or irritation : it is 1050; by Portal, Anat. torn. v. p. 401; the 

 by occurrences of this nature that the boasted latter, however, describes the urethral orifice as 

 and sometimes fortunate efficacy of certain surrounded by oblique muscular fasciculi, 

 lithontriptic medicines as cures for stone is to Winslow also, Anat. torn. ii. p. 210, denies a 

 be explained. true sphincter, but ascribes the office of such 

 The exact arrangement of the muscular fibres to the muscular fasciculi which pass from the 

 at the neck of the bladder has not been very pubis to the bladder. Wilson (Lectures on the 

 accurately explained ; some describe them as Urinary and Genital Organs, p. 57,) denies 

 arranged circularly so as to constitute a true the existence of any regular sphincter, but 

 sphincter : this opinion is maintained by John thinks, from the distribution of some fibres 

 Bell, System of Anatomy, vol. iv. p. 159 ; also at the beginning of the urethra, and which pass 

 by Palfin, Anat. torn. i. p. 163; by Meckel, round it semicircularly from the forepart and 

 Anat. vol. iii. p. 564 ; by Bayle and others, meet the descending fibres behind, that the 

 Sir Charles Bell also describes a sphincter contraction of these, assisted by those of the 

 vesicae to exist, but places it in a different situa- urethra nearer the penis (compressores urethrae), 

 tion from that usually assigned. His description may be considered as sufficient to prevent the 

 of this muscle is as follows : " to exhibit it, cut urine passing from the bladder into the urethra, 

 off all the appendages to the bladder except Several of the foregoing writers who deny a 

 the prostate gland, make an incision into the muscular sphincter to the bladder, consider, 

 fundus and invert it, dissect off the inner mem- nevertheless, that its orifice is closed by a pe- 

 brane from around the orifice of the urethra; culiar tissue which resists the ordinary tendency 

 a set of fibres will be discovered on the lower of the muscular coat to expel its contents, but 

 half of the orifice running in a semicircular which is capable of yielding to the increased 

 form round the urethra ; these make a band of force which is exerted in the ordinary evacua- 

 about half an inch in breadth, particularly tion. Thus Bichat describes, as placed between 

 strong on the lower part of the opening, and the mucous lining and the external cellular 

 having mounted a little above the orifice on tissue, a dense white fibrous substance, con- 

 each side, they disperse a portion of their fibres tinuous with the muscular fibres which are in- 

 in the substance of the bladder; a smaller and serted into it, a small process of this prolonged 

 weaker set will be seen to complete their course posteriorly to the uvula, and another anteriorly 

 surrounding the orifice on the upper part, to to the verumontanum. This substance is 

 these sphincter fibres' a bridle is joined which not muscular, and presents a passive organic 

 comes from the union of the muscles of the resistance. Cloquet, Boyer, and Marjolin con- 

 ureters ; this is the most posterior part of all cur in the same account ; it is difficult, how- 

 the muscles which embrace the urethra, it re- ever, to reconcile with such a condition of parts 

 sembles the sphincters of the other hollow vis- the phenomena which not unfrequently occur 

 cera; forexample,thatof thepyloricorificeof the in disease, such as paralysis and incontinence 

 stomach." ; The great ad vantage of the sphincter of urine in cases of injury of the spine, or of the 

 as thus described must be, as Sir C.Bell says, nervous system; or again, retention of urine 

 to prevent the fluids from the seminal vessels from irritation in this situation caused either by 

 and from the ducts of the prostate gland, falling local inflammation, or through sympathy with 

 b;ick into the bladder, as also to protect the ori- some adjacent diseased organ, or by some pe- 

 h'ces of these ducts from exposure to the urine culiar acrimony in the urine. A muscular struc- 

 when the bladder is closed, and that without ture is more reconcilable with these, and with 

 this arrangement it would be inconceivable how many other pathological facts, than an elastic, 

 the contents of the vesiculae seminales could be or fibrous, or resisting tissue, such as this part is 

 discharged forwards, or how the urine could be stated to be furnished with. The result of our 

 retained while the seminal discharge was being examination convinces us that the organization 

 made. We must remark, that after frequent of this part is very peculiar, and that the neck 

 examinations of this region, we cannot satisfy of the bladder is closed by a power more than 

 ourselves of the existence of this particular ar- thatof a mere elastic tissue. Elasticity no doubt 



resides in this structure, and we admit to a con- 



Treaiise on Diseases of the Urethra, &e. p. 14. siderable extent, as it does in almost every ani- 



