5 2 



THORAX 



which lines the inner surface of the fibrous sac, is called the 

 parietal layer, and the invaginated portion, which envelops the 

 heart, is the visceral portion. The inner surface of the sac is 

 lined by a flat endothelium, and, during health, is smooth and 



Inferior thyreoid 



I 

 Right common carotid artery ,'\ 



Right internal jugular vein 

 Right subclavian artery * 

 Right subclavian vei 



Left internal mammarj' ve 

 Right internal mammary.. 



vein 



Cut edge of fibrou: 



pericardium 



Superior vena cava 



Cut edge of serous 



pericardium 



Aorta 



Division of pul- 

 monary artery 

 Right pulmonary artery 

 Superior vena cava 

 Upper right 

 pulmonary vein 



Lower right pul- 

 monary vein 



Cut edges of 

 serous pericardium 



Inferior vena ca 



veins 



Left common carotid artery 



Left internal jugular vein 

 Thoracic duct 

 Left subclavian artery 

 Left subclavian vein 



Left phrenic nerve 



- Left vagus 

 Left superior intercostal vein 



Left recurrent nerve 

 Ligamentum arteriosum 



Left pulmonary artery 

 Arrow in transverse sinu.s 

 Left bronchus 

 Upper left pulmonary vein 



Lower left pulmonary vein 



Fibrous pericardium 

 us pericardium 



FIG. 24. The Pericardium and Great Vessels of the Heart. The thoracic 

 organs were hardened in situ by formalin injection. The pericardium 

 having been opened by the removal of its anterior wall, the great vessels 

 were divided and the heart removed. 



glistening. The parietal and visceral layers are separated, 

 during health, merely by a thin layer of serous fluid, which 

 prevents friction between the two surfaces as they move over 

 each other during the contractions and expansions of the 

 heart. 



