62 



ZOOLOGY. 



Smaller Circulation. 



Pulmonary Artery. 



Eight Auricle. 

 Heart. 1 



Venae Cavae. 



Eight Ventricle. ' 



Pulmonary Veins. 

 Left Auricle. 



Left Ventricle. 



Greater Circulation. 

 Fig. 47. Mammals and Birds. 



Smaller Circulation. 



Vense Cavae. 



Fig. 48. Eeptiles. 



Heart. 



Aorta. 



' Single Ventricle. 

 Greater Circulation. 



