Bacillus Rubidus. 



B. RUBEE BEROLINENSIS. 



Origin. — Water supply of Berlin. 

 Form. — Long, narrow rod; forms threads. 

 Motility. — Actively motile. 

 Sporulation. — No spores observed. 

 Anilin dyes. — Stain readily. 

 Growth. — Fairly rapid. 



Gelatin plates. — Small, yellow, finely granular colonies, with irreg- 

 ular border. It liquefies gelatin. 



Stab culture. — Gelatin slowly liquefies along line of inoculation. 

 A yellowish, mass of bacteria settles to the bottom, and a thin folded 

 scum forms on the surface. 



Streak culture. — On agar, it forms a thin, irregularly bordered, 

 slightly folded, yellowish growth. On potato, the most characteristic 

 growth forms; it spreads, and has a bright brick-red color. On blood- 

 serum, liquefaction takes place and a red pigment forms. 



Oxygen requirements. — It is aerobic. 

 Temperature. — It does not grow at the temperature of 

 the body. 



Behavior to gelatin. — Liquefies. 

 Pathogenesis. — No effect observed. 



An interesting red pigment-producing bacillus, allied 

 to the B. prodigiosus and to the Kiel bacillus, has been 

 found on freshly packed oil sardines, and also in the sup- 

 purating felons on the fingers of the packers. In the lat- 

 ter case it was associated with an anaerobe. 



About ten additional species or varieties of bacilli 



are known, that are characterized by the production of a 



red pigment. Moreover, a red pigment can be produced by 



various micrococci, sarcines, spirilla and yeasts. 



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