136 ELEMENTARY PHYSIOLOGY 



the right side to the left by means of the vessels of the lungs. 

 The other is the systemic circulation, or the circulation generally 

 through the whole system, commencing at the left ventricle, and 

 terminating at the right auricle. 





Fig. 128. Diagram illustrating the Circulation. 



i. right auricle ; 2, left auricle ; 3, right ventricle ; 4, left ventricle ; 5, vena cava superior ; 

 6, vena cava inferior ; 7, pulmonary arteries ; 8, lungs ; 9, pulmonary veins ; io ; aorta ; 

 ii, alimentary canal ; 12, liver ; 13, hepatic arteiy ; 14, portal vein ; 15, hepatic vein. 



The pulmonary circulation (Lat. pulmo, a lung) is not nearly 

 so extensive as the systemic, and less force is therefore needed to 



