URETHRA. 



12G7 



and extended half an inch back, and was so 

 tight that it scarcely admitted the finest probe. 

 My friend Curling also met with a case of 

 stricture, attended with retention of urine. 

 Being foiled in the introduction of the ca- 

 theter, he was compelled to puncture the 

 bladder in the direction of the canal beneath 

 the pubis. The disease had arisen from the 

 contusion to which the urethra had been sub- 

 jected in a protracted labour, which hail taken 

 place twenty-eight years before. Since that 

 time the woman had always experienced dif- 

 ficulty in making water, and had twice suffered 

 retention, but no catheter could ever be 

 passed. The aperture of the meatus was large, 

 and there was great induration around : a 

 small catheter was passed about an inch and 

 a half, but could not be made to enter the 

 bladder. The bladder was punctured, and be- 

 tween thirty and forty ounces of urine drawn 

 off. The stricture was afterwards dilated with 



bougies. 



COMPARATIVE ANATOMY. 



The comparative anatomy of the urethra 

 has been most carefully examined by Cuvier ; 

 and I have borrowed largely from his cele- 

 brated Lccons d' Anatomic Comparce, in my 

 description. 



Cuvier divides the "urethra into two por- 

 tions ; the first extends from the orifice of 

 the bladder to a short distance anterior to the 

 prostate, whilst the second is continued thence 

 to the orifice at the glans.1 



In the first portion of the canal in mam- 

 miferous animals generally, that is, in what is 

 termed in man the prostatic portion, we find 

 the verumontanum surrounded by prostatic 

 ducts and terminations of vasa ejaculatoria ; 

 whilst in many the sinus prostaticus is of an 

 enormous size : this is especially the case in 

 the elephant. 



In many animals we find temporary lon- 

 gitudinal folds of membrane : these are, 

 however, permanent in some, as in the mar- 

 mot : in this animal as many as twelve pass 

 off on each side, and, enclosing small spaces, 

 render the canal exceedingly irregular, and 

 thus retard the flow of urine and semen. 



With respect to the comparative length of 

 this part of the canal there is great variety. 

 Thus in man and the apes it is short, and 

 surrounded by the prostate. In the makis 

 it is long and slender; it is long in the 

 Chciraptea ; and of medium length in the 

 bears. In the hedgehog it is about one third 

 the entire length ; it is more than half in 

 the civet, cat, sarigitc, kangaroo, and phasco- 

 lome ; it scarcely reaches this length in the 

 giant kangaroo ; and is of less extent in the 

 dog. It is actually longer, and its diameter is 

 larger, in the marmot ; scarcely half the length 

 in the rat and guinea-pig ; somewhat less 

 than half in the hare ; short, and not a quar- 

 ter of the entire length in the squirrel; it 

 is not more than a third or fourth in the ele- 

 phant, Pachydermata, Solidungu/a, Ruminants, 

 the dolphin, and porpoise. It is usually re- 

 latively shorter in man and theses than in all 



other mammiferous animals ; and it is amongst 

 the Carnivora, in whom the penis is com- 

 paratively short, as the cat and civet, that it 

 appears to bear the largest proportion to the 

 other part of the canal. Cuvier denominates 

 this pelvic part of the canal the muscular por- 

 tion, because it is usually surrounded by a 

 muscular layer. Thus in man and the apes 

 this is especially remarkable on the sides of 

 the prostate, where the levator ani and leva- 

 tor prostate are situated. 



In the rest of the mammifera the muscular 

 layer is circular. In the Cheiroptera, mole, 

 hedgehog, and cat, it is remarkably thick ; in 

 the dog, civet, and sarigue it is thin ; it is 

 scarcely perceptible in the marmot, where there 

 is scarcely any thing more than a tendinous 

 covering. In the Rodents it is generally of 

 moderate thickness ; but in the Pachydermala 

 and Ruminants it is of great thickness. 



Cuvier suggests that the object of this mus- 

 cular layer is to expel the urine and seminal 

 secretion, by forcibly contracting the first por- 

 tion of the urethra ; and hence it is found so 

 fully developed in those animals whose penis 

 is long, as in the Ruminants, and in those in 

 whom that organ is short, as in the cat ; for in 

 the first it is requisite to force the fluid along 

 the lengthened penis, in the latter it becomes 

 necessary to expel it beyond the limits of the 

 penis. He says that this species of ejacula- 

 tion is requisite, when any obstacle exists in 

 the urethra, to the free discharge of semen, 

 as is the case in the porpoise and the dolphin, 

 where the membranous part of the urethra, 

 being wholly surrounded by the prostate, 

 forms an acute angle with the remainder 

 of the canal, and becomes considerably con- 

 tracted at that part. In these animals there 

 is a thick muscle, attached behind to the front 

 of the corpora cavernosa ; the fibres of which, 

 directed backwards, cover the prostate gland, 

 and pass as far as the under part of the neck 

 of the bladder. The office of this is neces- 

 sarily to overcome the difficulty in the expul- 

 sion of the contents of the urethra, arising 

 from the peculiarity just mentioned. 



In many animals, as in the Ruminants and 

 Pachydermata, the communication between 

 the former part of the urethra and the second 

 or spongy portion is by no means direct ; but 

 it takes place at the superior part of the 

 latter by a sort of opening at a short distance 

 from its commencement : this is the case also in 

 the wild boar. The spongy portion begins under 

 this condition in the form of a cul-de-sac of 

 varied diameter, a sort of bulb, into which 

 the semen is received after it has traversed 

 the muscular portion of the urethra, whilst 

 the secretion of Cowper's glands escapes into 

 its sides. In other cases, as in the squirrels 

 and marmots, this cul-de-sac receives only the 

 orifices of these glands, and continues in the 

 form of a short canal, which opens into the 

 urethra either at the middle of the penis, or 

 at a short distance beyond. The urethra in 

 this instance passes over it, and they are both 

 surrounded by the vascular tissue investing 

 the bulb. 



4 M 2 



