918 
at their extremities. The first of these ap- 
sey nae is due to the accidental position of 
é section under the microscope, so that the 
short trunk with its terminal twigs appears to 
be placed within the area of a vein projecting 
into it like a blossom on its stalk; the second 
results from the contraction of the coats of the 
artery, the effects of the longitudinal contrac- 
tion giving rise to the curve and to the enlarge- 
ment near its extremity, and the transverse 
contraction, by producing the expulsion of 
some part of the injection, to the conical form 
of the extremity itself. “ These remarkable 
arteries,” writes Miiller,* “ have a great re- 
semblance to the tendrils of the vine, only that 
the arteries are much shorter in proportion to 
their thickness; from this resemblance I have 
named them arterie helicine or tendril-like 
arteries. We may also compare their ends to 
the top of a crook. By close examination 
with the microscope they may be seen pro- 
jecting into the venous cells, not, however, bare, 
ut covered with a fine membrane that under 
the object-glass looks horny.” 
If the description which I have here given 
of erectile tissue be the true one, it is clear 
that the arterie helicine have no existence, and 
that that appearance of the small vessels, to 
which Miiller has given this name, is a neces- 
sary consequence of the natural distribution of 
the ordinary vessels of the organ. I may be 
permitted to remind my junior reader that it 
was through the medium of the arteriz heli- 
cine that Miiller supposed the venous canals 
of erectile tissue to be filled during erection, 
while, for the purposes of nutrition and main- 
taining the ordinary circulation of the organ, 
the arteries pour their blood into capillaries, 
and these into veins. Excepting during the 
moment of discharging their blood, this phy- 
siologist conceived that the small curved ter- 
minal twigs were impermeable, and that it was 
only under the influence of the erectile nervous 
function attending erection that the impetus 
of the arterial blood was sufficient to open the 
concealed apertures at their extremities. 
The lymphatic vessels of the penis are found 
chiefly on its dorsum, taking the course of the 
dorsal vein. At the root of the organ they 
curve outwards to the groin, and communicate 
with the upper group of inguinal glands. I 
have frequently seen a small lymphatic gland 
on the dorsum penis near its root. 
The nerves of the penis are derived from the 
internal pudic and from the hypogastric plexus; 
those from the former source are the anterior 
superficial perineal nerve, the nerve of the bulb, 
and the dorsalis penis nerve. 
The anterior superficial perineal is a branch 
of the perineal division of the internal ae 
It enters the perineum at the posterior border 
of the deep perineal fascia, and passing on- 
wards in the groove between the erector penis 
and accelerator urine, gives branches to the 
scrotum, and is finally distributed to the inte- 
gument of the under part of the penis as far as 
the prepuce. 
- * Archiv, 1835, 
PENIS. 
The nerve of the bulb is also a branch of the 
ineal division of the internal pudic, and 
ikewise enters the perineum through the 
sterior border of the deep perineal fascia. 
tween the superficial and deep fascia, and 
behind the transversus perinei muscle, the 
nerve passes obliquely forwards to the bulb, 
where it gives off pl long and slender 
branches, which run forwards on the fibrous 
tunic of the corpus spongiosum, and then 
enters the bulb in company with the artery, 
to be distributed to the vascular parenchyma 
of that body and to the urethra as far as the 
glans penis. 
The perineal division of the internal pudie 
nerve also gives branches to the acceleratores, 
erectores, and ischio-bulbosi muscles. 
The dorsal nerve of the penis is the superior 
or deep division of the internal pudic. This 
nerve accompanies the internal pudic artery to 
the anterior part of the arch of the pubis, 
where it pierces the deep perineal fascia and 
 aeeaig onwards to the dorsum penis. In the 
atter situation it lies externally and somewhat 
superficially to the dorsal artery, and enters the — 
base of the glans penis by several branches, to 
be distributed to the papille of that body. — 
Near the root of the penis the dorsal nerve 
gives off a large branch, which passes obliquely 
along the side of the corpus cavernosum, 
divides into numerous long and slender branches, 
which are distributed to the integument of the — 
apeee and lateral aspect of the penis, to the 
fibrous covering and substance of the corpus 
cavernosum, and to the prepuce. The ne 
dorsales communicate with each other, on 
dorsum penis, by anastomosing filaments. 
The nerves derived from the hypogastric 
plexus are slender ramuscules, which accom- 
pany the arteries of the corpus cavernosum and 
ulb into the interior of the penis, and are dis- 
tributed to its internal structure. ; 
Developement.—The first indication of th 
developement of a penis is eived towards — 
the end of the fifth week after concep ion, & 
which time it exists in the form of a sligl 
prominence, situated immediately in front ¢ 
the common urino-sexual aperture. By th 
seventh or eighth week this prominence assumt 
the lengthened character of the future orga 
and is grooved along its under side, the groo 
being an extension of the common urino-sexu 
cleft. The glans penis makes its appearan 
during the ninth week, and the urinary groo 
is continued beneath it. During the tenth 
eleventh weeks the urinary groove becot 
separated from the anus by the 
transverse septum, and the borders of the gro 
begin to lengthen and coalesce on the me¢ 
line,dn order to form the urethra. This proe 
commences from behind, and proceeds” 
wards towards the glans, attaining its com 
tion at about the fifteenth or sixteenth ¥ 
When it remains imperfect from arrest of dé 
lopement, it constitutes that form of deficien 
which is termed Hypospadias. The prep’ 
is developed at the same time with the clos t 
of the urethra. & 
( Erasmus Wilse 
aed 
