to a sac of large dimensions, which rested against the
rectum. In such a case as this, the sac, occupying a lower position than
the base of the bladder, must first become the recipient of the urine,
and retain this fluid even after the bladder has been evacuated, either
voluntarily or by means of instruments. If, in such a state of the
parts, retention of urine called for puncturation, it is evident that
this operation would be performed with greater effect by opening the
depending sac through the bowel, than by entering the summit of the
bladder above the pubes.

[Illustration]
Plate 63,--Figure 3, 4.

FIG. 4, Plate 63.--The vesical orifice is obstructed by two portions, 3,
4, of the prostate, projecting upwards, one from each of its lateral
lobes, 6, 6. The bladder is thickened and fasciculated, and from its
summit projects a double sac, 1, 2, which is invested by the
peritonaeum.

FIG. 5, Plate 63.--The prostatic canal is constricted and bent upwards
by the third lobe. The bladder is thickened, and its base is dilated in
the form of a sac, which is dependent, and upon which rests a calculus.
An instrument enters the bladder by perforating the third lobe, but does
not come into contact with the calculus, owing to the low position
occupied by this body.

[Illustration]
Plate 63,--Figure 5.

FIG. 6, Plate 63.--Two sacs appear projecting on either side of the base
of the bladder. The right one, 5, contains a calculus, 6; the left one,
of larger dimensions, is empty. The rectum lay in contact with the base
of the bladder between the two sacs.

[Illustration]
Plate 63,--Figure 6.

FIG. 7, Plate 63.--Four calculi are contained in the bladder. This organ
is divided by two septa, 2, 4, into three compartments, each of which,
1, 3, 5, gives lodgment to a calculus; and another, 6, of these bodies
lies impacted in the prostatic canal, and becomes a complete bar to the
passage of a catheter. Supposing lithotomy to be performed in an
instance of this kind, it is probable that, after the extraction of the
calculi, 6, 5, the two upper ones, 3, 1, would, owing to their being
embedded in the walls of the bladder, escape the forceps.

[Illustration]
Plate 63,--Figure 7.

FIG. 8, Plate 63.-Two large polypi, and many smaller ones, appear
growing from the mucous membrane of the prostatic urethra and vesical
orifice, and obstructing these parts. In examining this case during life
by the sound, the two large