BACILLUS PROTEUS VULGARIS. 539 



twelve hours reached 38.8 C.; an erysipelatous-like 

 swelling of the forearm occurred, and the glands in 

 the axilla were swollen and painful. Neumann has 

 obtained the bacillus pyocyaneus in pure culture in 

 two cases of hsematemesis and melsena of the new-born 

 from the blood and other organs. Lartigau found it 

 in well-water, and in great abundance in the intestinal 

 discharges of a number of cases made ill by drinking 

 the water. 



We may, therefore, conclude from these facts that 

 the bacillus pyocyaneus, although ordinarily non-patho- 

 genic for man, may under certain conditions become a 

 dangerous source of infection. Children would seem 

 to be particularly susceptible to this infection. 



The differential diagnosis of the pyocyaneus from 

 other fluorescing bacteria is easy enough as long as it 

 retains its pigment-producing property. When an agar 

 culture is agitated with chloroform a blue coloration 

 demonstrates the presence of this bacillus. When the 

 pyocyanin is no longer formed, however, the diagnosis 

 is by no means easy, particularly when the pathogenic 

 properties are also gone. 



BACILLUS PROTEUS VULGAEIS. 



This bacillus, which is one of the most common and 

 widely distributed putrefactive bacteria, was discovered 

 by Hauser (1885) along with other species of proteus 

 in putrefying substances. These bacteria were formerly 

 included under the name a bacterium termo " by previous 

 observers, who applied this name to any minute motile 

 bacilli found in putrefying infusions. 



Morphology. Bacilli varying greatly in size; most 

 commonly occurring 0.6// broad and 1.2/* long, but 



