CHAPTER XVI 



HUMAN LUNG, RED CORPUSCLES OF 

 THE BLOOD, AND HUMAN TOOTH 



Human Lung. 



A VEEY tiny portion of the human lung 

 -*-^- is shown in Fig. 50. The section is 

 taken transversely through a small bronchus 

 which appears in the illustration as the largest 

 of the openings. Connected with it is a mucous 

 gland. Sections of an artery and a vein can 

 be seen near the bronchus. 



Four or five smaller openings, having a star- 

 like structure, are bronchioles (air tubes). Near 

 the bronchus, but lying on the side opposite 

 the mucous gland, are two curved, dark 

 objects. These are sections through two por- 

 tions of cartilage. 



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