332 BACTERIOLOGY. 



ganism when cultivated for a time on artificial media 

 rapidly loses its pathogenic properties. If, therefore, 

 failure to reproduce the disease after inoculation 

 with old cultures should occur, it is in all probability 

 due to a loss of virulence of the organism. 



FIG. 63. 



f , 



Bacterium pneumonice in blood of rabbit. Stained by method of Gram. 

 Decolorization not complete. 



This organism was discovered by Sternberg in 1880. 

 It was subsequently described by A. Friinkel as the 

 etiological factor in the production of acute fibrinous 

 pneumonia. 



It is not uncommonly present in the saliva of healthy 

 individuals, having been found by Sternberg in the oral 

 cavities of about 20 per cent, of healthy persons examined 

 by him, and certain authors are of the opinion that it 

 occurs in the oral or nasal cavities of all individuals 

 at various times during life. It is constantly to be 

 detected in the rusty sputum of patients suffering from 

 acute fibrinous pneumonia. Its presence has been de- 

 tected in the middle ear, in the pericardial sac, in the 

 pleura, and in the serous cavities of the brain; and 



