86 



ESSENTIALS OF BACTERIOLOGY 



Varieties. Asporogenic. By cultivation in gelatine, contain- 

 ing 1 to 1000 ac-carbolic, a variety develop that cannot produce 

 spores. Also involution farms, differing from the usual type. 



FIG. 44. 



FIG. 45. 



Stab Cultures of Anthrax in Gelatine. 



Staining. They readily take all the aniline dyes with the 

 ordinary methods. To bring out the cup-shaped concave ex- 

 tremities, a very weak watery solution of methylin blue is best. 



Spores are stained by the usual method. When several bacilli 

 are joined together, the place of their joining looks like a spore 

 because of the hollowed ends. The double staining will develop 

 the difference. 



Sections of tissue are stained according to the ordinary 

 methods, taking Gram's method very nicely. 



Pathoyeneste. When mice are inoculated with anthrax mate- 

 rial through a wound in the skin, they die in twenty-four hours 



