806 THE VASCULAR SYSTEM. 
the gluteus maximus, whilst others pass through it, near its origin, to the overlying skin. 
The branches freely anastomose with branches of the sciatic, internal pudic, internal 
circumflex, deep circumflex iliac, and lateral sacral arteries. 
(4) The deep terminal branch, ac ‘companied by thes superior g eluteal nerve, runs forwards 
between the gluteus medius and minimus, and, after giving a nutrient branch to the ilium, 
immediately subdivides into upper and lower branches. The upper branch, running 
forwards along the origin of the gluteus minimus from the middle curved line of the 
ilium, passes beyond the anterior margins of the gluteus medius and minimus to anasto- 
mose, under cover of the tensor fascia femoris, with the ascending branch of the external 
circumflex artery. It also anastomoses with the circumflex iliac artery, and it supplies 
muscular branches to the adjacent muscles. The /ower branch passes more directly 
forwards, across the gluteus minimus, towards the trochanter major, along with the 
branch of the superior gluteal nerve which supplies the tensor fascize femoris. It supplies 
the glutei muscles, and anastomoses with the ascending branch of the external circumflex 
artery. 
Before leaving the pelvis the gluteal artery gives muscular branches to the pelvic 
diaphragm and the obturator internus, small neural branches to the roots of the sacral 
plexus, and nutrient branches to the hip-bone. 
BRANCHES OF THE ANTERIOR DIVISION OF THE INTERNAL ILIAC ARTERY 
The anterior division gives off both parietal and visceral branches, and is 
continued as the hypogastric artery, which for the greater part of its extent is 
obliterated. The parietal branches are the obturator, the pudic, and the sciatic. 
The visceral branches include the superior, middle and inferior vesical, and the 
middle hemorrhoidal arteries in the male. Similar visceral branches are also 
given off in the female, but the inferior vesical is replaced by the vaginal artery, 
and an additional branch, the uterine artery, 1s also given off. 
VISCERAL BRANCHES. 
1. The superior vesical artery (a. vesicalis superior) arises from the anterior 
division of the internal iliac. It divides into numerous branches which supply 
the upper part of the bladder, anastomosing with the other vesical arteries, and 1t 
also gives small branches to the urachus, and often to the lower part of the 
ureter. It may in addition give off the middle vesical artery, and not un- 
frequently the long slender artery to the vas deferens arises from one of its 
branches. 
2. Obliterated Hypogastric Artery.— Atrophy of that portion of the internal 
iliac artery, which extends from the side of the bladder to the umbilicus (a. umbili- 
ealis), has already been referred to. It is complete between the umbilicus and 
the true origin of the superior vesical artery, but between this origin and the 
apparent ending of the internal iliac in its two divisions the atrophy is ; incomplete, 
and the lumen of the vessel, though greatly diminished in size, remains, and is 
looked upon as the first part of the superior vesical artery. Strictly speaking, the 
first of these two parts only constitutes the “ obliterated hy pogastric ” (ligamentum 
umbilcale laterale). It is a fibrous cord which runs forwards and upwards 
towards the apex of the bladder, whence it ascends on the posterior surface of 
the anterior abdominal wall and on the outer side of the urachus to the umbilicus. 
As it passes along the wall of the pelvis it is under cover of the peritoneum, and it 
is ae by the vas deferens in the male,and by the round hgament in the female. 
The middle vesical artery is usually given off behind the superior vesical. 
It is erdistibuted to the posterior surface of the bladder as low down as the base ; 
and to the vesicule seminales. 
4. The inferior vesical artery (a. vesicalis inferior) is a very constant branch 
which runs inwards upon the upper surface of the levator ani to the base of the 
bladder. It also gives branches to the seminal vesicles, the vas deferens, the lower 
part of the ureter and the prostate, and it anastomoses with its fellow of the 
opposite side, with the other vesical arteries, and with the middle hemorrhoidal 
artery. 
