THORACIC CAVITY 



49 



and the sternum, and it bears the impressions of the costal 

 arches. 



The medial surface is separable into an anterior or 

 mediastinal portion and a posterior or vertebral portion. The 

 vertebral portion lies against the sides of the bodies of the 

 vertebrae (Figs. 5, 20, 21, 22). The mediastinal part is 



-CEsophageal area 



Tracheal and vagus 

 area 



Groove for azygos 

 vein 



FIG. ic 



Groove for right subclavian artery 



Groove for lower end of internal j 

 jugular vein"! 



Groove for ist ril 



Groove for superior ^_ 

 vena cava ~*~ 



Groove for ascending 

 aorta, thymus, ancl"*~ 

 areolar tissue 



Depression for 

 right atrium 



Groove for in- 

 ferior vena cava 



Pulmonary 

 ligament 



FIG. 19. The Medial Surface of a Right Lung hardened in situ. 



applied against the mediastinal partition and presents 

 markings which are the exact counterparts of the inequalities 

 of the corresponding surface of the mediastinum. Thus, 

 it is deeply hollowed out in adaptation to the pericardium, 

 upon which it fits (Figs. 5, 21). The pericardial con- 

 cavity occupies the greater part of the mediastinal surface, 

 and, owing to the greater projection of the heart to the 

 left side, it is much more extensive in the left lung than in 

 the right lung. 



VOL. II 4 



