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ever, obviously only of secondary value, since in a plate in 

 which colonies of B. typhosus or B. Gaertner are numerous 

 those that are in more crowded position are always much 

 smaller, although not slower in coming up, than where the 

 colonies are more isolated. 



This last fact applies not only to Drigalski plates, or to the microbes at 

 present under consideration, but it applies to all kinds of microbes, and to all 

 kinds of cultures, viz., where isolated and sufficiently apart from one 

 another the colonies are much larger than in places where they are more 

 crowded. 



A more important difference is the fact that in the hanging 

 drop made with a small particle of a colony many of the 

 bacilli are seen to be arranged in longer or shorter chains, a 

 fact not observed in similar colonies (from Drigalski medium) 

 of B. typhosus or B. Gaertner. 



Sub-cultures made in the different media soon decide the 

 separate position of the microbe under consideration, for on 

 the gelatine surface it forms a slow-growing translucent 

 film ; in gelatine shake culture colonies do not appear in the 

 deeper parts, but are all crowded on and near the surface of 

 the gelatine, and it does not form gas in glucose gelatine ; in 

 litmus milk (at 37 C.) it forms strong alkalescence (blue) 

 after some days ; neutral red broth (at 37 C.) after some 

 days is turned orange, with slight fluorescence ; MacConkey 

 fluid (at 37 C.) remains unaltered ; it grows only very feebly 

 in phenol broth at 37 C. ; no agglutination is observed with 

 typhoid blood serum or with Gaertner blood serum even in 

 moderately high dilutions (e.g., 1 in 100) if a particle of a 

 recent gelatine culture is submitted to the test. 



As stated above, this microbe is of constant and of fairly 

 numerous occurrence in sewage and in faecal matter; its 

 colonies on Drigalski medium resemble by their colour and 

 general aspect those of B. typhosus, the bacilli are short 

 cylindrical, very motile and forming chains, and, as just 

 detailed, are in all media in sub-culture distinctly and easily 

 differentiated from B. typhosus and -from B. Gaertner. It is 

 further to be remembered that unlike the typhoid-like 

 colonies not capable of growing at 37 C., mentioned on a 



