THE RESPIRATORY ORGANS 



The two rounded or oval nostrils, present at 

 the base of the beak, lead into short and rather 

 narrow nasal cavities. Each cavity is separated 

 from its fellow by a septum, partly bony and 

 partly cartilaginous, and contains three carti- 

 laginous representatives of the turbinated bones 

 or conchse of mammals. 



Associated with the nose is a small, flattened 

 nasal gland lying on the frontal bone close to 

 the medial angle of the eye. The duct of the 

 gland runs for some distance on the lateral 

 wall of the nasal cavity before opening into 

 the interior. 



In the floor of the pharynx is a com- 

 paratively narrow, elongated opening which 

 leads into the cranial larynx (F g. 11). The 

 opening is not provided with any cartilaginous 

 representative of the mammalian epiglottis, 



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