THE CLASSIFICATION OF BACTERIA 233 



Habitat. Water, sewage. Moore (U. S. Dept. of Ag. Bureau of Animal 

 Industry, Bull. 10, 1896, 45) .holds B. zea Burrill (bacterial disease of 

 corn) to be identical with B. cloaca. The corn bacillus as described by 

 Moore 5s characterized as follows : Bacilli 1 .3-2 /x. ; occur singly, usually in 

 short chains and clumps. 



Agar slant. Growth grayish, viscid. 



Gelatin stab. Gelatin slowly liquefied along needle track ; on the surface the 

 growth is grayish, beneath which the gelatin is softened; liquefaction 

 occurs slowly ; liquefied gelatin clear, with a viscid, grayish sediment ; 

 reaction alkaline. 



Potato. Growth dull, grayish, not viscid. 



Bouillon. Turbid in 24 hours. 



Milk. Coagulated in 18 days. 



Glucose bouillon. Gas and acid. 



Saccharose bouillon. Gas. 



Lactose bouillon. Gas developed more slowly. 



Pathogenesis. Non-pathogenic to mice, guinea pigs, and rabbits. 



71. B. fermentationis 



B.fastidus-liquefaciens Tavel : Ueber Aetiol. der Strumitis, Basel, 1892. 

 Gelatin stab. Liquefaction along the line of stab, with a bad odor. 

 Glucose bouillon. Gas. 

 Milk. Not coagulated. 

 Bouillon. Turbid, with a membrane. 



72. B. formosus Ravenel 



l.C, 12. 



Morphology. Bacilli slender; ends rounded, 7-1 1 times their breadth. 



Motility slight. 

 Gelatin colonies. The deep colonies are round, entire, yellowish, and slightly 



granular ; the surface colonies are round, entire, yellowish ; centres gray, 



edges granular ; later a concentric structure. 

 Agar slant. Growth white, moist, glistening, limited ; edges notched. 

 Gelatin stab. Growth crateriform, becoming stratiform. 

 Potato. Growth moist, white, spreading to creamy. 

 Bouillon. Turbid, with a sediment. 

 Litmus milk. Alkaline, becoming decolorized in 10 days. Indol negative. 



Grow at 37 ; optimum 20 . 

 Habitat. Water. 



