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BACILLUS NEAPOLITANUS. Emmerich. 



(1884). 

 EMMERICH'S BACILLUS. 



Origin Found first in the blood, organs and intestinal 

 contents of cholera cadavers in Naples. Has since been 

 shown to be normally present in feces ; it occurs in air and 

 in putrid fluids. Is closely related to the B. coli comraunis. 



Form. Small, short rods with rounded ends ; usually 

 single, rarely in long threads. 



Motility. Has no motion. Brownian movement 

 marked. 



Sporulation. Not observed. When desiccated re- 

 tains it vitality for some time. 



Anilin Dyes. Stains readily, but not by Gram's 

 method. 



Growth. Is rather rapid, even at ordinary temper- 

 ature. 



Plates. On gelatin plates the deep colonies are small, round or whet- 

 stone shaped, yellowish-brown, finely granular and may show concentric 

 rings. The surface colonies spread freely as a thin plaque with irregular or 

 wavy border. A delicate marking or venation can be seen in young colonies. 

 No liquefaction. 



Stick Cultures. Are characterized by a pronounced surface growth on 

 the gelatin. It spreads rapidly over the surface as dry, grayish white, irreg- 

 ularly bordered mass. Abundant growth along the stich. In old cultures the 

 gelatin frequently becomes cloudy due to acid production and bundles of 

 crystals appear. 



Streak Cultures. On agar forms a moist, white, spreading growth. On 

 potatoes it develops as a yellowish- brown sticky mass. 



Oxygen requirements. Is a facultative anaerobe. 



Temperature. Grows readily at ordinary tempera- 

 ture and at 37 C. 



Behavior to Gelatin. Does not liquefy. 



Aerogenesis. Not observed. 



Pathogenesis. Fatal results in guinea-pigs, rabbits, 

 etc., may follow the injection of large quantities of the 

 pure culture. It is a toxicogenic organism. 



