THE ABDOMINAL AORTA 669 



The ovarian arteries (aa. ovaricae) (Fig. 474) in the female correspond to the 

 spermatic arteries in the male. They supply the ovaries, and are shorter than the 

 spermatic. The origin and course of the first part of each artery are the same as 

 the spermatic in the male, but on^arriving at the margin of the pelvis the ovarian 

 artery passes inward, between the two layers of the broad ligament of the uterus, 

 to be distributed to the ovary. Small branches go to the Fallopian tube, the ureter, 

 and the broad ligament; and one passes on to the side of the uterus and anasto- 

 moses with the uterine arterv. Other offsets are continued along the round 

 ligament through the inguinal canal, to the integument of the labium and groin. 



At an early period of fetal life, when the testes or ovaries lie at the side of the 

 vertebral column below the kidneys, the spermatic or ovarian arteries are short ; 

 but as these organs descend from the abdomen into the scrotum or pelvis, the 

 arteries gradually become lengthened. 



The inferior phrenic arteries (aa. phrenicae inferiores) (Fig. 467) are two small 

 vessels which present much variety in their origin. They may arise separately 

 from the front of the aorta, immediately above the coeliac axis, or by a common 

 trunk, which may spring either from the aorta or from the coeliac axis. Some- 

 times one is derived from the aorta, and the other from one of the renal arteries. 

 In only one out of thirty-six cases examined did these arteries arise as two separate 

 vessels from the aorta. They diverge from one another across the crura of the 

 Diaphragm, and then pass obliquely upward and outward upon the under surface 

 of the Diaphragm. The left phrenic passes behind the oesophagus and runs for- 

 ward on the left side of the cesophageal opening. The right phrenic passes behind 

 the inferior vena cava, and ascends along the right side of the aperture for trans- 

 mitting that vein. Near the back part of the central tendon each vessel divides 

 into two branches. The internal branch runs forward to the front of the thorax, 

 supplying the Diaphragm, and anastomosing with its fellow of the opposite side, 

 and with the musculophrenic and comes nervi phrenici branches of the internal 

 mammary. The external branch passes toward the side of the thorax and anasto- 

 moses with the intercostal arteries and with the musculophrenic. The internal 

 branch of the right phrenic gives off a few vessels to the inferior vena cava, and 

 the left one some branches to the oesophagus. Each vessel also sends glandular 

 branches (rami suprarenales superior) to the suprarenal glands of its own side. 

 The spleen and the liver also receive a few branches from the left and right vessels 

 respectively. 



The lumbar arteries (aa. lumbales) are in series with the intercostals. They 

 are usually four in number on either side, and arise from the back part of the aorta 

 opposite the bodies of the upper four lumbar vertebrae. A fifth pair, small in 

 size, is occasionally present; it arises from the middle sacral artery. They run 

 outward and backward on the bodies of the lumbar vertebrae, behind the sympa- 

 thetic cord, to the intervals between the adjacent transverse processes, and are 

 then continued into the abdominal wall. The arteries of the right side pass behind 

 the inferior vena cava, and the upper two on each side run behind the corresponding 

 cms of the Diaphragm. The arteries of both sides pass beneath the tendinous 

 arches which give origin to the Psoas magnus, and are then continued behind this 

 muscle and the lumbar plexus. They now cross the Quadratus lumborum, the 

 upper three arteries running behind, the last usually in front of the muscle. At 

 the outer border of the Quadratus lumborum they pierce the posterior aponeurosis 

 of the Transversalis abdominis and are carried forward between this muscle 

 and the Internal oblique. They anastomose with the lower intercostals, the sub- 

 costal, the iliolumbar, the deep circumflex iliac, and the deep epigastric arteries. 



Branches. In the interval between the adjacent transverse processes each 

 lumbar artery gives off a dorsal branch (ramus dorsalis), which is continued back- 

 ward between the transverse processes and is distributed to the muscles and skin 



