916 
so large that it extended forwards to the middle 
of the penis, and usu the place of the 
accelerator urine, which was absent. The 
ischio-bulhbosus muscle is separated from the 
transversus perinei by the folded border of the 
deep and superficial perineal fascie, and from 
the compressor urethre by the anterior layer 
of the deep perineal fascia. It covers in the 
internal pudic vessels and nerve. 
The action of the ischio-bulbosi muscles is 
to compress the bulb, and by their pressure to 
aid the posterior fasciculi of the acceleratores 
urine in producing turgescence of the corpus 
spongiosum. In the variety to which I have 
alluded above, the ischio-bulbosi must have 
performed the whole of the duty of the accele- 
ratores. 
The compressor vene dorsalis penis is a small 
muscle, first described by Dr. Houston,* of 
Dublin. According to that gentleman it is 
found very commonly among mammiferous 
animals, and also in the human subject when 
the muscular system is well developed. To 
its existence in the dog and cat I can bear 
witness, having repeatedly prepared it for 
Dr. Jones Quain, who was wont to demon- 
strate it in his lectures; I have been less suc- 
cessful in the human subject, and have never 
obtained a satisfactory view of a distinct pair 
of muscles in the situation indicated by Dr. 
Houston. “In man,” writes this author, “the 
compressores vene dorsalis are less distinct 
than in most of the mammalia. They arise 
from the rami of the pubis above the origin of 
the erectores penis and crura, and ascending in 
a direction forwards are inserted above the 
vena dorsalis by joining with each other in the 
mesian line. They form a thin stratum of 
muscular and tendinous fibres about an inch 
long and three quarters of an inch broad, and 
may perhaps be looked upon as portions of the 
erectores penis, which, instead of being inserted 
into the sides and lower part of the corpora 
cavernosa, mount over those bodies to exert 
their compressing influence on the vena dor- 
salis. They enclose between these and the 
penis, the veins, arteries, and nerves of this 
region. Their anterior fibres are distinguished 
from those of the erectores by the fibrous at- 
tachment of the crura to the pubis; their 
posterior margins are kept distinct from the 
* front part of the levatores ani, known under 
the name of Wilson’s muscles, by the pudic 
artery, which divides them in its course towards 
the dorsum of the penis.” 
“The best procedure to display these mus- 
cles is the following. Detach the bladder and 
levator ani with the hand from one side of the 
pelvis; then divide with the saw the pubis and 
ischium about one inch from the symphysis, 
and break off the bones at the sacro-iliac arti- 
culation; next dissect away carefully the re- 
maining portion of the pubis from the symphy- 
sis, periosteum, and crura penis, and then the 
compressores vene, bearing still their natural 
relations to the crura and other muscles, may 
be exposed with very little difficulty. The 
* Dublin Hospital Reports, vol. v. page 459. 
PENIS. 
insertion of the muscles being in a great mea- 
sure outside the pelvis, they may also be 
demonstrated without the section of the bones, 
by cutting on them in front of the pubis and 
looking carefully for their tendon at the side of 
the vena dorsalis: from the tendon the knife 
may be carried downwards and backwards in 
the course of the fibres, and nearly the whole 
of the muscle can be thereby exposed. It 
must, however, be remembered that it will be 
needless to search for them in a thin emaciated 
individual, where the other muscles of the 
perineum are so pale and soft that even they 
can scarcely be distinguished. The subject 
should be robust, and the muscles red, in order 
to demonstrate them.” 
Respecting the action of these muscles Dr. 
Houston observes: “The use of the musculi 
compressores vene is self-evident and cannot 
be mistaken ; the effect of their contraction will 
be to close the vein and mechanically obstruct 
the current of blood. A simple experiment 
will prove to demonstration that such will be 
the necessary result of their contraction. Let 
the muscles be stretched in the natural direction 
of their fibres, and any fluid forced into the — 
vein will not find a passage through the vessel 
beyond the spot where it is compressed by 
their tendon: a very gentle pull of the muscles 
will be sufficient to produce this effect. In 
cases where the vein runs through the tendon — 
the pressure will be most efficacious, but 
in those in which the tendon is arched over the 
vein its descent from the contraction of the — 
muscles will sufficiently compress the delicate 
tunics of the vessel to produce the required 
effect.” A 
The arteries of the re are derived from 
the internal pudic, itself a branch of the inter-— 
nal iliac artery. They are three in number on 
each side; the artery of the bulb, the artery of 
the corpus cavernosum, and the arteria dors 
penis. 
The arteria corporis bulbosi is given off from 
the internal pudic at a point corresponding 
with the level of the urethra, and passes trans 
versely inwards to the bulb, which it ente 
close to the lower part of the urethra. In it 
course inwards it lies along the upper borde 
of the transverse portion of the compress¢ 
urethra muscle, and crosses that muscle 0 
liquely from within outwards. It is situatet 
between the two layers of the deep perine 
fascia, and is surrounded by a sheath derive 
from the anterior layer of the fascia as it ente 
the bulb. Having entered the corpus spe 
osum, the artery runs forwards in the midst 
the venous canals of that body to the gla 
nis, in which it distributes its ultims 
ranches. In its course the arteria bulbe 
gives off numerous ramuscules, which ram 
in the walls of the venous canals. 
Lhe arteria corporis cavernosi is given © 
from the internal pudic, somewhat nearer 
the symphysis pubis than the preceding, 
opposite the point of junction of the er 
penis; it pierces the fibrous tunic of the ef 
penis on its inner side, to enter the stractu 
of the corpus cavernosum. In the latte 
. 
+ 
