PEELIMINART EEMAEKS. 221 



The larynx is occasionally the seat of Laryngitis, Spasm of 

 the Larynx, Atrophy of its muscles, which latter is productive 

 of Eoaring. It is also liable to Ossification, Abscess, and to 

 Stricture of the organ. 



The mucous tissues of the trachea are subject to Inflamma- 

 tion both of an acute and chronic character, and to the formation 

 of Abscess within its structures. 



The bronchial tubes are subject to a disease called Bron- 

 chitis, both of an acute and chronic form ; also to Spasm of the 

 smaller tubes or air-cells, and to the formation of Abscess. 



The structures of the lungs are subject to Inflammation, to 

 the formation of Abscess, to Tubercle, to Broken AVind, and to 

 Thick Wind ; also to rupture of the blood-vessels, and to 

 melanotic deposits. 



The diaphragm is liable to Spasm, and to Eupture of its 

 tissues. 



The pleura is subject to acute inflammation, of a form 

 which is exceedingly prone to eflusion of serum and lymph. 



The ribs are liable to fracture, and to injuries of greater or 

 less severity. 



Many of the above-named diseases are essentially similar in 

 character, the difference in name arising merely from the dif- 

 ference in the locality in which they are manifested ; as, for 

 example. Laryngitis, Tracheitis, and Bronchitis, which are simply 

 inflammatory affections of the mucous membrane — a membrane 

 alike common to the larynx, the trachea, and the bronchial 

 tubes. It extends, in fact, from the commencement of the 

 nasal openings to the utmost limit of the bronchial tubes. 



Some of the diseases enumerated are far more common 

 than others affecting the same tissues. Catarrh is more com- 

 mon than Ozena ; Bronchitis more so than local inflammation 

 of the trachea, ending in Abscess. The latter is more likely 



