32 UNIVERSITY OF MISSOURI STUDIES 



it is in contact with the oesophagus and descending aorta. 

 A small part of the internal surface of each lung reaches the 

 heart external to the oesophagus and aorta (Plates VIII 

 and IX). Below the disc between the seventh and eighth 

 thoracic vertebrae, the aorta is separated from the heart by 

 the left half of the oesophagus. From above downward, 

 more and more of the posterior surface of the heart is cov- 

 ered by the inferior lobe of the left lung. 



Inferiorly, the right auricle and internal part of the 

 right ventricle rest upon the central tendon of the dia- 

 phragm, while the remainder of the right ventricle and 

 the left ventricle rest upon the internal muscular portion 

 of the left dome. These portions of the heart are in rela- 

 tion through the diaphragm with the left lobe of the liver. 

 They lie on a line which runs outward, forward 

 and slightly downward from the disc between the eighth 

 and ninth vertebrae to the anterior extremity of the 

 left fifth rib. From Plates XXVIII and XXXII it 

 appears that the heart is in relation with the fundus of 

 the stomach, but Plate XIII shows that the lower part of 

 the pericardial cavity is separated from the stomach by the 

 left lobe of the liver. The apparent intimate relation be- 

 tween the apex of the heart and the upper pole of the spleen 

 is of the same nature (Plates XIII, XXXI and XXXV). 



The position and relations of the heart in this cadaver 

 dififer somewhat from those given in many topographic 

 anatomies. Cunningham^ gives photographs of formalin 

 hardened bodies, with the heart exposed, which show the 

 heart to be about 2 cm. lower on the anterior wall, than in 

 these projections. Quain° gives practically the same posi- 



^Thane, G. D., Quain's Elements of anatomy. Angeiology, II. ii. 

 London, 1896. 



