86 ESSENTIALS OF BACTERIOLOGY. 



FIG. 46. Properties. Very motile; gases arise 



with butyric smell. In solutions of sugars, 

 lactates and cellulose-containing plants, 

 and vegetables, it gives rise to decomposi- 

 tions in which butyric acid is often formed. 

 Casein is also dissolved. 



Like granulose, a watery solution of 

 iodine will color blue some portions of the 

 bacillus ; therefore it has been called amy- 

 lobacter. 



Qrowih. It is strongly anaerobic, and 

 has not yet been satisfactorily cultivated. 



Bacillus Lactis Cyanogenus. Bacterium 

 Bacillus Amyiobacter. Syncyanum. (Huppe.) 



Origin. Found in blue milk. 



Form. Small narrow rods about three times longer than they 

 are broad ; usually found in pairs. The ends are rounded. 



Properties. They are very motile ; do not liquefy gelatine ; 

 form spores usually in one end. A bluish-gray pigment is formed 

 outside of the cell, around the medium. The less alkaline the 

 media the deeper the color. It does not act upon the milk other- 

 wise than to color it blue. 



Growth. Grows rapidly, requiring oxygen. Colonies on plate. 

 Depressed centre surrounded by ring of porcelain-like bluish 

 growth. Dark brown appearance under microscope. 



Stab Culture. Grows mainly on surface ; a nail-like growth. 

 The surrounding gelatine becomes colored brown. 

 Potato. The surface covered with a dirty blue scum. 

 Attenuation. After prolonged artificial cultivation loses the 

 power to produce pigment. 



Staining. By ordinary methods. 



Bacillus Lactis Erythrogenes. Bacillus of Eed Milk. (Huppe 

 and Grotenfeldt.) 



Origin. Found in red milk, and in the faeces of a child. 

 Form. Short rods, often in long filaments, without spores. 

 Properties. Does not possess self-movement. Forms a nause- 

 ating odor ; liquefies gelatine. Produces a yellow pigment which 

 can be seen in the dark, and a red pigment in alkaline media, 



