218 MICROBIOLOGY 



still liquid and colonies developed within the medium. Later 

 M'Fadyean and Stockman found that very small isolated 

 greyish speck-like colonies would appear in the thin film of 

 medium on the surface. It was also found that it grew on the 

 surface of ordinary agar but quite slowly. It will grow also 

 in an atmosphere of pure oxygen. 



Agar. When agar is inoculated with the natural material 

 the growth is very slow often requiring ten days for its ap- 

 pearance. The isolated colonies are at first of a greyish color 

 and later they become brownish. M'Fadyean and Stockman 

 state that on agar the colonies first appear like very minute 

 dew drops on the surface and later they develop into a delicate 

 bottle-green tint and still later become a brownish tint. Dense 

 masses of the bacteria collect in the water of condensation. 

 Glycerine added to the agar does not increase the growth. In 

 agar tubes inoculated after the Liborius method the colonies 

 may appear under the surface. In plate cultures the growth 

 seems to be more uncertain. 



Gelatin. It does not grow on gelatin. 



Potato. Potatoes are not satisfactory for obtaining 

 original cultures but they are excellent for subcultures. On 

 this medium the organism gives at the beginning a honey- 

 yellow transparent looking viscous growth. It requires from 

 5 to 8 days for it to appear. With continued incubation the 

 growth slowly increases in thickness, becomes opaque, and 

 deepens in color, passing from the original yellow, through a. 

 ruddy tint, to a brown or chocolate one. M'Fadyean and 

 Stockman, called attention to the resemblance of the growth of 

 this organism on potato to that of glanders. It is differenti- 

 ated from it by its slow growth. They consider the growth on 

 potato the most distinctive of the cultural characteristics. 



Agar-gelatin-raw serum (Stribolt's medium). Bang 

 found that in this medium the organism was practically 

 anaerobic as determined by the deep inoculation (Liborius' 

 method). M'Fadyean and Stockman describe the growth as 

 follows: "When the Stribolt medium was sown with exudate 



