94 ACTINOMYCETES 



Potato: Growth fair, raised, wrinkled, cream-colored, later yellowish gray 

 to dull brownish. Aerial mycelium absent or trace of white. 



Gelatin: Liquefaction slow. No pigment produced. 



Milk: Peptonization complete in 3 to 4 weeks at 30°C, without any pre- 

 vious coagulation. The reaction becomes faintly acid (pH 6.0 or less). 



Starch: Hydrolysis. 



Cellulose: Decomposed readily by some strains. 



Nitrate: No reduction with sucrose as source of energy. 



Sucrose: Inversion. 



Antagonistic properties: Positive. 



Remarks: Aerial mycelium on certain media (glucose or glycerol-aspara- 

 gine agar) becomes moistened and exhibits dark, glistening patches. These 

 patches, when touched with a needle, prove to be a moist, smeary mass of 

 spores. This characteristic feature is not equally distinct in all strains. 



97. Streptomyces longisporoflavus (Krassilnikov) comb. nov. (Kras- 

 silnikov, N. A., Actinomycetales, Akad. Nauk. USSR, Moskau, 1941, 30.) 



Vegetative growth: Colonies yellow, lemon-yellow or dirty yellow, sel- 

 dom golden yellow. Pigment insoluble in medium. 



Aerial mycelium: Well-developed, velvety, whitish yellow to brownish 

 yellow. Sporophores produce long open spirals. Spores cylindrical or elon- 

 gated, 1.0-1.5 by 0.7/*; some with rounded ends and swollen in center. 

 ^Gelatin: Liquefaction medium, 10-15 days. 



Milk: Coagulation; peptonization slow. 

 . Starch: Hydrolysis weak. 



Cellulose: No growth. 



Nitrate: Reduction strong. 



Sucrose: No inversion. 

 , Antagonistic properties: Weakly antagonistic. 



Remarks : Some strains have a greenish tinge, depending on composition 

 of medium. 



98. Streptomyces candidus (Krassilnikov) comb. nov. (Not Strepto- 

 thrix Candida Petruschky.) (Krassilnikov, N. A., Actinomycetales, Akad. 

 Nauk. USSR, Moskau, 1941, 49.) 



Vegetative growth: Organism grows well on various media. 



Aerial mycelium: Sporophores long, straight or wavy, but never forming 

 spirals. Spores cylindrical, elongated, 1.5-2.0 by 0.7m; on maturing, some 

 become more rounded. 



Synthetic agar: Colonies well-developed, colorless, not pigmenting me- 

 dium. Aerial mycelium cottony white. 



