COMPARATIVE ANATOMY 63 



14. Renal Arteries. — These arise from the aorta and pass 

 directly to the kidneys. Each usually divides before entering 

 the kidney. 



15. Internal Spermatic Arteries (ovarian in the female). 

 These arise from the aorta posterior to the kidneys. In the 

 male each passes with the vas deferens to the testis and scrotum; 

 in the female the ovarian leads to the ovary and cranial end of 

 the uterus. 



16. Inferior Mesenteric Artery. — ^This vessel arises 

 from the aorta at about the level of the last lumbar vertebra 

 and supplies the colon and rectum. 



17. Ilio-lumbar Arteries. — These two arteries arise from 

 the aorta about two centimeters caudal to the inferior or mesen- 

 teric and pass to the iliopsoas muscles along the dorsal body 

 wall. 



18. External Iliac Arteries. — The aorta divides and 

 forms the two external iliacs which go to the legs. After leaving 

 the body cavity they are known as femoral arteries. 



19. Hypogastric Arteries. — These usually arise from a 

 continuation of the aorta, but may come from one of the external 

 iliacs. Their branches are very variable, but supply mainly 

 the urogenital organs, rectum, and certain pelvic muscles. 



20. Sacralis Artery. — This is the continuation of the aorta 

 into the sacral and tail regions. 



21. Profunda Femoris Artery.— Originating from the 

 femoral artery at the point where it leaves the abdominal cavity, 

 it divides into branches going to the tissues of the median surface 

 of the thigh and to the ventral wall of the abdomen. The 

 remainder of the femoral passes down the leg. 



22. Femoral Artery. — The femoral is the large artery of 

 the leg. Trace the main branches. 



Internal Anatomy of the Heart of the Cat 



Remove the auricular appendages and the dorsal wall of 

 each auricle, except where the veins enter. Insert the point of 

 the scissors into the pulmonary artery and continue the cut 

 through the right ventricle. Bisect the left ventricle into dorsal 

 and ventral halves. Remove any clotted blood that may be 

 present. It should now be possible to clearly see the internal 

 structures of the heart. 



