THE RABBIT 20$ 



ture and lighter in color than the veins. Find a large 

 curved blood vessel, aorta, coming from the heart and 

 curving back on the dorsal side. From what part of the 

 heart does it come? On top of the arch a short distance 

 from the heart find a large branch turning to the right of 

 the animal, the innominate artery. This soon divides, send- 

 ing one branch, the left carotid, to the left side of the neck 

 and head, and divides into the right subclavian, going to the 

 right side and shoulder; and also the right carotid, going 

 to the right side of the neck and head. Trace these as far 

 as you can without mutilating the specimen. Returning to 

 the aorta, the left subclavian artery leaves the arch beyond 

 the innominate artery and goes to the left shoulder. Trace 

 it as far as you can. Just beyond the left subclavian on 

 the aorta there arises the first pair of intercostal arteries. 

 Others arise between each pair of ribs. From the sub- 

 clavian arteries on either side, an artery is seen running 

 posteriorly under the ribs. These are the mammary ar- 

 teries, and they return to the mammary veins which were 

 seen on the outside of the muscular wall. 



(f) Trace the aorta, which is called the dorsal artery, 

 backward, lifting the left lung, to the posterior part of the 

 body. Just back of the diaphragm it gives off the coelic 

 artery, which further divides, giving one branch to the liver 

 and one to the stomach. Further back it again divides, fur- 

 nishing the renal arteries to the kidneys, the femoral ar- 

 teries to the hind legs, and the lumbar arteries, which go 

 dorsally to furnish blood to the strong muscles of the back. 

 Trace these arteries as far as you can conveniently, and 

 make a diagram representing the arterial circulation as you 

 have it exposed from the left side of the animal's heart. 



