236 THE DOG-FISH 



surface of the stomach, and divides into two 

 main branches, one of which supplies the 

 proximal end of the stomach and the liver, 

 and the other the first part of the intestine 

 and the pancreas. 



iii. The mesenteric artery is a median vessel arising 

 from the aorta about an inch and a half behind 

 the cceliac arteryT It supplies the intestine 

 and rectum, and gives branches to the genital 

 organs. 



iv. The lieno-gastric artery is a median vessel 

 arising from the aorta immediately behind the 

 mesenteric artery. It supplies the loop of 

 the stomach between its proximal and distal 

 limbs, and also the spleen and part of the 

 pancreas. 



v. The posterior mesenteric artery is a small median 

 vessel arising from the aorta about an inch 

 and a half behind the lieno-gastric, and run- 

 ning backwards in the mesentery to the rectal 

 gland, which it supplies. 



vi. The parietal arteries are small paired vessels 

 arising at intervals along the whole length of 

 the aorta, and supplying the body-walls. 



vii. The renal arteries are small paired vessels 

 arising from the aorta along the greater part 

 of its length, and supplying the kidneys, which 

 they enter from the dorsal surface. 



Ths dissection of the renal arteries should he postponed 

 until after the dissection of the reproductive organs and 

 cloaca. 



To see the arteries, dissect one kidney away from the body- 

 wall and turn it inwards, so as to expose its dorsal surface. 



viii. The iliac arteries are a pair of small vessels 

 leaving the aorta near the hinder end of the 

 body-cavity, and running outwards in the body- 

 walls to the pelvic fins, which they supply, 



