DISSECTION OF THE VASCULAR SYSTEM. 53 



each side, going directly to the kidneys. The artery 

 on the left side is somewhat posterior to that on the 

 right. Each artery as it enters the hilus of the kidney 

 splits into two or more branches. 



7. Muscular Branches. Posterior to the renal arteries 

 several muscular branches may arise which are dis- 

 tributed to the muscles of the abdominal wall. 



8. The Spermatic Arteries. In the male they form 

 two small branches of the aorta arising some distance 

 posterior to the renals and going to the testes. They 

 pass to the inguinal canal, and reach the testes in the 

 spermatic cords. In the female they are known as the 

 ovarian arteries, and pass more directly outward to 

 reach these bodies, being distributed to them and to 

 the anterior portion of the oviducts. 



9. The Inferior Mesenteric Artery comes off from the 

 aorta some distance posterior to the spermatics, and is 

 distributed to the rectum and to the lower portion 

 of the large intestine. 



10. The Iliac Arteries. Below the inferior mesenteric 

 the aorta divides into three branches, the two external 

 iliacs and a median trunk ; this latter soon divides again 

 into three branches, the two internal iliacs and a 

 median sacral or caudal artery. 



11. The Internal Iliacs. Open the pelvis as directed 

 in the dissection of the reproductive organs. Each 

 internal iliac gives off just beyond its origin a small 

 branch, the superior vesical, which passes to the blad- 

 der ; each iliac then divides into two main branches, 

 the pudic and the sciatic. The pudic lies more to the 

 outer side ; followed out it breaks into two branches, 

 one of which, the internal pudic, is distributed to 

 the genital organs in the pelvis — in the female to 

 the vagina, vestibule, and uterus ; the other seems to 



