CIRCULATION OF THE BLOOD. 



sides of the thorax and secured. The neck should be well stretched 

 and secured in the head-holder. A simple way of doing this is to 

 pass a short thick glass rod or wire nail through the mouth, behind 

 the teeth, and tie about the jaws and to the board behind the head. 



FIG. 31. Extrinsic Cardiac Nerves of Rabbit. C, Carotid artery; V, vagus nerve; 

 D, depressor nerve ; Sy, sympathetic nerve ; S.L, superior laryngeal nerve. 



Open the trachea by a transverse incision. Introduce and tie in 

 the tracheal cannula. Connect this with some form of artificial 

 respiratory apparatus and start artificial respiration at about the 

 same rate that the rabbit was breathing before. 



Make a median incision through the skin of the thorax down to 

 the sternum and as far down a&.its lower end. With heavy scissors 



