CHAPTER XI 

 Diseases of the Respiratory System 



ANATOMY AND PHYSIOLOGY 



The respiratory organs of birds are the nasal passages, the 

 pharynx, larynx, 

 trachea, lungs and 

 air sacs. The form 

 and general appear- 

 ance of the lungs 

 and trachea are 

 shown in Fig. 25. 



The respiratory 

 apparatus differs 

 somewhat in struc- 

 ture and function 

 from that of mam- 

 mals. As in mam- 

 mals the trachea 

 (windpipe) divides 

 into the primary 

 bronchi, one pass- 

 ing to each lung. 

 In birds these 

 bronchi do not di- 

 vide and subdivide ^^^ 25. — Photograph of the lungs of a do- 

 as in mammals, but mestic fowl. The air passages are injected 



each passes to the with gelatine. (Original.) 



147 



