200 



TEE CAT. 



[chap. VII. 



are called anricles, and the other two, ventricles— onQ of each on 

 each side. The auricle and ventricle of the right side are com- 

 pletely divided off from those of the left side. The auricles open 

 into the ventricles hy valvular apertui'es, and valves guard the 

 openings of the great vessels. 



Such heing a summary of its main characters, its various parts 

 need examination in detail. 



The heart of the cat lies on the ventral side of the body, within 



LV 



TCI 



Fig. 102.— Cat's Heart cut open. 



A. The left sitle, 



B. The right side. 



a. Style passing up through inferior vena cava 



to right auricle. 

 AO. Aorta. 

 h. Stj'le passing down from the vena az^-gos 



through superior vena < ava into riglit auricle. 



c. St>'le passing down from the superior vena 



cava into the right auricle. 

 CA. Conus arteriosus. 

 cl. Left carotid. 

 cr. Tliglit carotid. 



d. Stylo ]iassing from conns arteriosus into left 



brancli of pulmonary artery. 

 tf. stylo passing up from left ventricle into 



aoi-ta. 

 FO. Place where the foramen ovale existed in 



the fcetus. 



(J, li, i. Styles passing tlu-ougli pulmonaiy vein 



into left auricle. 

 lA. Left auiicle. 

 LV. Left ventricle. 

 MV. Mitral valve. 

 n. Innominate artery. 

 I'AL. Left lirancli of pulmonary artery. 

 FAR. Right liranch of pulmonaiy aitery. 

 RA. Riglit .auricle. 

 RV. Right ventricle. 

 si. Left sul)-cla\ian artery. 

 HLV. Semi-lunar valve. 

 sr. Right sul)-elavian artery. 

 TL. Tubercle of Lower. 

 VCI. Inferior vena cava. 

 T'Cb". Suijcrior vena cava. 



the thorax, upon the inner surface of the sternum and between the 

 two lungs. It is almost globular in shape, but slightly narrows 

 towards its posterior end or apex, which touches the anterior 

 surface of the diaphragm. 



At its opposite end, or base, the lioart is connected with several 

 groat blood-vessels, but elsewhere its surface is free. 



The pericardium is a bag of dense fibrous tissue witli an epithelial 

 lining, and contains— like the peritoneum — a serous fluid. This 



