RESPIRATORY ORGANS. 



which is situated in the neck, directly over the oesopha- 

 gus, and communicates with the mouth by an opening, 

 which, you will recollect, we have already noticed. 



Emily. The chink of the glottis one of the seven 

 openings into the pharynx ; I recollect it. 



Dr. B. The air-tubes, and perhaps the air-cells, are 

 lined with mucous membrane similar to ihat which lines 

 the alimentary canal. In this engraving you have a di- 



agram of the lungs, and thebronchiae leading into them, 

 toether with the distribution and re-union of the vessels. 



