788 PATHOGENIC MICROORGANISMS 



variations in reaction, growing equally well upon neutral, slightly 

 acid, or slightly alkaline culture media. Glycerin or small quantities 

 of glucose added to media seem to render them more favorable for 

 the cultivation of this bacillus. 



Upon agar the colonies show little that is characteristic. They 

 appear after twenty-four hours at 37.5 C. as yellowish-white spots, 

 at first transparent, later more opaque. They are round, with an 

 even border, and microscopically appear finely granular. The older 

 the cultures are, the more yellow do they appear. 



On gelatin at room temperature, growth is slow, grayish-white, and 









FIG. 83. GLANDERS BACILLUS. From potato culture. (After Zettnow.) 



no liquefaction of the gelatin occurs. Growth upon this medium 

 is never abundant. 



In broth, there is, at first, diffuse clouding, later a heavy, tough, 

 slimy sediment is formed. At the same time the surface is covered 

 with a similarly slimy pellicle. The broth gradually assumes a dark 

 brown color. 



In milk, coagulation takes place slowly. In litmus milk, acidifica- 

 tion appears. 



The growth upon potato presents certain features which are diag- 

 nostically valuable. On potatoes which are not too acid growth 

 is abundant and within forty-eight hours covers the surface as a 

 yellowish, transparent, slimy layer. This gradually grows darker 



