366 



THE HEART. 



Fig. 318. SEMIDIAGRAMMATIC REPRESENTATION OP THE CHEST, TO SHOW THE POSITION OF THE HEART 



AND GREAT VESSELS, AS SEEN BEHIND THE STERNUM AND COSTAL CARTILAGES. (A. Thomson, modified 



from Luschka.) 



The lungs have shrunk from the front of the chest. The heart is slightly higher than during life, 

 and the aorta more to the right. a, right clavicle ; b, scalenus anticus muscle ; c, sterno-mastoid 

 muscle divided ; d, pectoral muscles divided ; + , nerves of brachial plexus above the subclavian 

 artery ; e, trachea below the isthmus of the thyroid body ; /, /, upper surface of diaphragm ; 

 g, g, lungs : g', on the left side, apex of the lung appearing in the neck ; h, right, ti, left lobe of the 

 liver ; i, stomach ; k, k, transverse colon ; I, to X, first to tenth ribs near their cartilages ; 1, placed 

 on the lower part of the manubrium of the sternum, and over the arch of the aorta (indicated by 

 outlines) ; 2', placed in the second left intercostal space, on the trunk of the pulmonary artery ; 3, 

 appendix of the right auricle ; 3', on the atrium, behind the third space ; 3", its lower part at the 

 junction of the sixth costal cartilage with the sternum ; 4, left auricular appendix ; 5, 5, right 

 ventricle ; 6, left ventricle ; 6', apex of the heart : the white line outside the heart is intended to 

 indicate the external pericardium, as if the anterior half were removed by a transverse incision ; 

 7, 7, vena cava superior ; 8, 8, internal jugular veins ; 9, 9, subclavian veins, joining the jugular ; 

 9-7, 9-7, innominate veins ; the position of the first part of the innominate, left carotid and left 

 subclavian arteries is indicated behind and below the left innominate vein ; 9', 9', outer parts of the 

 subclavian vessels. It is to be observed that in this figure the attachment of the sixth costal cartilage 

 to the sternum is represented a little too high. 



