136 GENERAL BIOLOGY. 



examination of the reproductive organs, 

 etc.) 



9. The posterior mesenteric artery, unpaired, to 

 the rectum. 



10. The sacral artery from the dorsal side of the 



dorsal aorta, unpaired, to the tail. 



11. The iliac arteries, the two branches into which 



the dorsal aorta divides at its posterior 

 end. Each of these gives off: 



(a) The ilio-lumbar artery to the body-wall, 



and divides into : 



(b) The internal iliac artery, to the pelvis. 



(c) The external iliac artery, which gives off 



an artery to the bladder and becomes 

 the femoral artery to the hind leg. 

 II. The Pulmonary Artery. 



(These are best seen when taking out the 



heart and lungs. IY. C.). 

 From the ventral side of the right ventricle 

 a vessel passes anteriorly, and, curving 

 around the dorsal side of the heart, divides 

 into right and left branches to the right 

 and left lungs. 

 Diagrams ! 



C. The heart. Find its parts again ; then liga- 

 ture the posterior vena cava near the 

 heart and take out the heart. 

 To remove the heart cut through all the veins and 

 arteries (leaving the ends attached to the heart 



