54 ACTINOMYCETES 



Fats: Hydrolysis and utilization rapid. 



Paraffin: Growth good, with spiral-forming sporophores and spherical 

 spores. 



Antagonistic properties: Strongly antagonistic. 



Remarks: This species represents a widely distributed group of organ- 

 isms, including such forms as Actinomyces parvus of Krainsky and others. 



29. Streptomyces griseolus (Waksman) Waksman and Henrici. 

 (Waksman S. A., Soil Sci., 8, 1919, 121.) 



Aerial mycelium: No spirals observed. Conidia spherical or oval-shaped. 



Synthetic agar: Growth colorless, thin, spreading, chiefly in the medium; 

 surface growth limited almost entirely to the aerial mycelium. Aerial 

 mycelium at first gray, later becoming pallid, neutral-gray. 



Nutrient agar: Growth brownish, with smooth surface. 



Glucose agar: Growth spreading, both on the surface and into the me- 

 dium; center raised, cream-colored, turning dark. 



Potato: Growth cream-colored, becoming black, spreading. 



Gelatin: Liquefaction, with yellowish, flaky pellicle and sediment. 



Milk: Growth abundant, pink pellicle; coagulation; peptonization, be- 

 coming alkaline. 



Starch: Growth grayish brown with dark ring. Hydrolysis. 



Glucose broth: Ring thick, brown. 



Nitrate: Reduction to nitrite. 



Temperature: Optimum 25°C. 



Antagonistic properties: Considerable activity against various bacteria; 

 some of the strains show negative activity. 



Remarks: Faint brownish soluble pigment formed. 



30. Streptomyces fasciculus (Krassilnikov) comb. nov. (Krassilnikov, 

 N. A., Actinomycetales, Akad. Nauk. USSR, Moskau, 1941, 51). 



Vegetative growth: Growth good, lichnoid colorless, covered with dark 

 gray, powdery or velvety aerial mycelium. 



Aerial mycelium : Sporophores straight, short, arranged in broom-shaped 

 bodies or fascicles. Spores oblong, 1.0-1.5 by 0.7 /x- 



Synthetic agar: See Vegetative growth. 



Nutrient agar: Aerial mycelium poorly developed, gray. 



Potato: Growth heavy, folded, with well-developed, dark gray aerial 

 mycelium. Soluble pigment brown. Sporophores and spores same as on 

 synthetic agar. 



Gelatin: Liquefaction medium. 



Milk: Coagulation and peptonization ready. 



Starch : Hydrolysis rapid. 



