LUNGS. 87 
What products are found in the bronchi in a case of acute croupous 
pronchitis ? 
Masses of fibrin, pus and desquamated epithelium. Sometimes the 
stroma of the mucous membrane is infiltrated with fibrin and pus. 
What is the product of a chronic croupous bronchitis ? 
There is an exudation of a large amount of fibrin, which coagulates 
in the form of a cast of the bronchi affected. After a time these casts 
are expectorated. Microscopically the wall of the bronchus is little 
altered. 
What is a bronchiectasia ? 
It is a dilatation of a bronchus and may be fusiform, sacculated or 
cylindrical. 
What new growths are found in the bronchi ? 
The walls may become ossified. Lipomata have been found. Car- 
cinomata and sarcomata rarely occur here as primary growths; usually 
they are secondary. 
LUNGS. 
What are the two kinds of emphysema ? 
Interlobular and vesicular. 
What are the changes in an interlobular emphysema ? 
Some of the air spaces are ruptured, and the air escapes into the inter- 
stitial tissue of the lung. If the pulmonary pleura is ruptured, air 
escapes into the pleural cavity (pneumo-thoraz). 
What changes are observed in the lung tissue in a case of vesicular 
emphysema ? 
Both lungs are increased in size. There may be pleuritic adhesions. 
The muscular portion of the wall of the bronchi may be thickened or 
the entire wall thickened and infiltrated with cells. The cells lining 
the air spaces are increased in size and number. The walls of the air 
spaces may be thickened or the air spaces may be dilated, their walls 
thinned and perforated with small holes which, later, may become larger. 
What are the changes in atelectasis ? 
If due to congenital causes there is not much change from the 
appearance presented by foetal lung. If this part of the lung remains 
unaérated the affected area becomes hard and firm. If the atelectasis 
is due to a plugging of one or more bronchi with pus, etc., or to com- 
pression or stenosis, the walls of the air spaces collapse. If the 
