54 



THORAX 



superior mediastinal part of the oesophagus, or it is separated 

 from it by a quantity of areolar tissue (Figs. 20, 22, 23). 



The anterior and posterior borders of the lung are in 

 marked contrast with each other. The anterior is compara- 

 tively short and thin, and it extends medially into the costo- 



Second costal cartilage Sternum Internal mammary vessels 



, ^mm*?/ 



Pectoralis major 

 Right pleural cavity 



Remains of thymus 



Right phrenic nerve 

 Superior vena cava 



Lymph glands 



- g x >* Trachea 

 *~&ff( Right vagus nerve 



y~, =p (Esophagus 



Intercostal vessels 



Cavity of left pleura - 



Left lung 

 (upper lobe) 



Lymph glands 



Arch of aorta 



Left phrenic nerve -- 



.v w^ 

 Left vagus nerve ^ 



Left recurrent nerve * 



Lymph glands 

 Thoracic duct 



Intercostal vessels - 



Cavity of left pleura 



Intercostal vessels - 

 Left lung (lower lobe) * 



Fourth thoracic 

 "vertebra 

 - Intercostal artery 



Cavity of right pleur 



FIG. 23. Transverse section of the Thorax of a Male Adult 

 along the plane B-B, Fig. 15. 



mediastinal sinus of the pleura, which lies posterior to the 

 sternum and the costal cartilages. It commences at the apex, 

 curves downwards, forwards and medially, posterior to the 

 sterno-clavicular articulation, to the lower border of the 

 manubrium sterni, and then it descends to the base. Im- 

 mediately below the highest point of the apex it is grooved 



