NON-PATHOGENIC BACTERIA. 223 



gelatin; aerobic; does not form spores; grows rapidly at 

 l lie ordinary temperatures upon the common media. Gel- 

 atin cultures give off a powerful, foul odor of trimethyl- 

 amin. It produces a greenish, fluorescent pigment, best 

 seen in transparent media; on potato the growths form a 

 thin, gray to brown, slimy layer. 



There are several other fluorescing bacilli, mostly found 

 in water. 



Bacillus Indicus. Found by Koch in the stomach-con- 

 tents of an ape in India ; a fine short bacillus with rounded 

 ends; motile; does not form spores; facultative anaerobic; 

 liquefies gelatin; grows rapidly, best at 35 C. upon the 

 ordinary media ; produces a brick-red pigment. Very large 

 doses injected into rabbits caused death in three to twenty- 

 four hours. 



Bacillus prodigiosus. \Yiclely disseminated in the at- 

 mosphere of certain places ; a short bacillus with rounded 

 ends, in form often nearly like the micrococci ; facultative 

 anaerobic; not motile, as a rule; does not form spores; 

 liquefies gelatin rapidly; grows rapidly, best at 25 C. on 

 the ordinary culture-media; milk is coagulated; gas forms 

 in sugar-media : cultures on potatoes give off a foul odor 

 of trimethylamin. A brilliant red color, which only de- 

 velops in the presence of oxygen, appears in cultures. The 

 pigment appears as granules outside of the bacteria. 



Bacillus violaceus (of Berlin). Found in water; a slim 

 rod with rounded ends which may form threads; actively 

 motile; facultative anaerobic; liquefies gelatin rapidly; 

 forms endogenous spores placed near the centers of the ba- 

 cilli ; grows rapidly, and not at high temperatures, upon 

 ordinary media, forming a deep, violet-colored pigment. 

 There are several bacilli related to this one. 



Bacillus amylobacter (Clostridium butyricum, Bacillus 

 butyricus, Prazmowski). Found widely distributed in na- 



