GLANDERS BACILLUS 185 



early and fatal cases, the agglutinating reaction is not available, 

 since it takes some time for the agglutinins to form in the blood. 

 Under the chapter on immunity an account of the PfeifTer reaction 

 is given, also one on vaccination against cholera infection, by means 

 of killed cultures, under the chapter on vaccines. 



Vibrios Allied to the Cholera Vibrio. 



Several other vibrios have been discovered that resemble the 

 cholera vibrio. These are mostly found in potable waters, and 

 though in many respects identical with the cholera vibrio, they 

 differ in essential points, i.e., pathogenicity, and in their agglutina- 

 bility. with specific sera. The most important of these organisms 

 are: Vibrio Metchnikovii; Vibrio proteus; Vibrio tyrogenum; and 

 Vibrio sclmylkilliensis. There are no important pathogenic mem- 

 bers of this group except the cholera vibrio. 



GLANDERS BACILLUS. 



Bacterium Mallei. 



Bacillus Mallei. 



Glanders Bacillus. 



Morphology and Stains. Slender rods 2 to 3^ in length, con- 

 taining no true spores, but shining chromatophilic bodies (Babes- 

 Ernst granules). In old culture, long club-like threads appear, 

 which exhibit true branching. This organism is not motile, and 

 has no flagella. It is stained with difficulty by ordinary methods, 

 and not at all by Gram's method. 



Vital Activities. It is a facultative aerobe, growing feebly in 

 the absence of air, and best at 37 C.,*in glycerine agar. Resists 

 drying but feebly. Its thermal death-point is 55 C., 10 minutes' 

 exposure. 



Chemical Activities. Produces a brown pigment on potato, also 

 mallein, and a little indol in old bouillon cultures. It forms no gas. 



