The spermatic arteries [a.spermaticae], two small and very long vessels, arise from the fore part of the aorta, a little below the renal arteries. In the fetus they are short, as the testes, at an early period of development, are placed immediately beneath the kidneys; but the arteries become gradually lengthened as these organs are moved from the abdomen into the scrotum.
Each spermatic artery is first directed outwards and downwards, crossing the ureter, and resting on the psoas muscle ; after passing over the external iliac artery, it turns forwards to the internal abdominal ring, where it comes into contact with the vas deferens. With this and the other constituents of the spermatic cord, the artery courses along the inguinal canal and descends to the scrotum to be finally distributed to the testis, after reaching the back part of that gland and anastomosing there with the artery of the vas deferens. The spermatic arteries are covered by the peritoneum until they reach the internal ring. Near the testis they become tortuous.
In the female, the arteries corresponding to the spermatic arteries in the male, named the ovarian, are shorter than those vessels, and do not pass out of the abdominal cavity. Their origin, direction, and connexions in the first part of their course, conform to what obtains in the male ; but at the margin of the pelvis they incline inwards, and running tortuously between the layers of the broad ligaments of the uterus, are guided to the attached margin of the ovaries, which they supply with branches. Some small branches can also be traced along the round ligament into the inguinal canal, and others along the Fallopian tubes. One, continuing inwards towards the uterus, joins with the uterine artery.
The spermatic arteries occasionally'arise by a common trunk. Two spermatic arteries are not unfrequently met with on one side ; both of which usually arise from the aorta, though one may be a branch from the renal artery. A case has occurred of three arteries on one side, — two from the aorta and the third from the renal.
