312 



INTEENAL ANATOMY OF HORSE. 



opening between the left auricle and ventricle by the mitral 

 valve, which has two flaps only. The auricular portion can be 

 told from the ventricular by an external constriction. From 



Fia, 102. — Diagram of the Circulatiox of the Blood. 



LA and RA, Left and right auricles; f, ventricles; L, lungs; Li, liver; J, intes- 

 tines ; A.vc, anterior or superior vena cava ; P. vc, posterior or inferior veua cava ; A.a, 

 aortic arch ; ^.ao, P.ao, anterior and posterior aorta; J7fl, hepatic artery; ifu, hepatic 

 vein; Pv, portal vein ; Pu.A, pulmonary artery; Pti.V, pulmonary veins; Pc, posterior 

 capillaries; Td, thoracic duct. 



these chambers arise the blood-vessels. In the right auricle 

 {RA) we find three tubes — (i) the supmor vena cava {Av£); 

 (ii) the ivferior vena cava (P.vc) ; (iii) numerous small veins 



