Twelfth Annual Report of the Bureau of Science— 1913.] 



Fig. 1. Lung of guinea pig which died 

 of advanced plague infection, 

 after being exposed to air in 

 which plague bacilli were sus- 

 pended by means of spraying. 



Fig. 2. Lung of monkey which died of pneumonic-plague 

 infection from inhalation, showing progression of 

 lesions; lobular and lobar pneumonia. 



Fig. 3. Lung of dog with pneumonic plague. 

 PLATE II. 



