THE RESPIRATORY SYSTEM. 



171 



FIG. 81. PHOTOGRAPH OF A LUNG CORROSION OF A PUMA IN MORPHO- 

 LOGIC MUSEUM OF PRINCETON UNIVERSITY. The specimen was 

 prepared by Mr. Sylvester. The trachea with all its ramifications 

 was injected with white paraffin, and the pulmonary artery^with red 

 paraffin, after which the lung substance was eaten away with acid. 



tr, Trachea; br, bronchus; b, bronchia; c, bronchiole. The pulmonary 

 artery and its branches are much darker than the air tubes. 



