THORAX 



in situ, it bears on its surface impressions and elevations 

 which are an exact counterpart of the inequalities of the 

 structures with which its surfaces are in contact at the 

 moment of fixation. 



In the natural condition each lung resembles half a cone, 

 and it presents for examination an apex, a base, a costal 

 surface, a medial surface. An anterior and a posterior border 

 separate the medial from the lateral surface ; and an inferior 

 or basal border separates the base from the medial and lateral 



Trachea 



Subclavian sulcu 

 Groove caused 

 by the first rib 



Subclavian sulcus 



Groove caused 

 by the first rib 



Lower lobe 



Cardiac notch 



jwer lobe 



FIG. 14. The Trachea, Bronchi, and Lungs of a Child, hardened 

 by formalin injection. 



surfaces. The apex rises into the root of the neck for one 

 and a half inches above the level of the anterior part of the 

 first rib, and it is crossed by the Subclavian artery, which 

 makes a groove upon the anterior border, a short distance 

 below the summit, although the artery is separated from the 

 lung by the membranous cervical diaphragm (Sibson's fascia), 

 and by the pleura. 



The base of each lung has a semilunar outline and is 

 adapted to the upper surface of the diaphragm. Consequently 

 it is deeply hollowed out, and, as the right cupola of the 



