SPECIES OF STREPTOMYCES 95 



Nutrient agar: Growth good, lichnoid or smooth ; aerial mycelium whitish. 



Gelatin : Liquefaction slow. 



Milk: Coagulation and peptonization weak. 



Starch: Hydrolysis rapid. 



Cellulose: Growth good. 



Nitrate: Reduction positive. 



Sucrose: Inversion. 



Antagonistic properties: Weak. 



99. Streptomyces alboflavus (Waksman and Curtis) Waksman and 

 Henrici. (Waksman, S. A., and Curtis, R. E., Soil Sci., 1, 1916, 99-134.) 



Aerial mycelium: Straight, branching, with very little tendency to form 

 spirals; very few oval-shaped spores formed. 



Synthetic agar: Growth glossy, spreading, colorless, becoming yellowish. 

 Aerial mycelium white, powdery, with yellow tinge. 



Nutrient agar: Growth restricted, cream-colored; no soluble pigment. 



Glucose agar : Growth restricted, much-folded, cream-colored with sulfur- 

 yellow surface; no soluble pigment. 



Potato: Growth wrinkled, moist, cream-colored. 



Gelatin: Surface growth abundant, colorless. Liquefaction slow, occur- 

 ring in 35 days. 



Milk: Surface ring pinkish. No coagulation. Peptonization, becoming 

 alkaline. 



Starch: Growth thin, spreading, yellowish. Hydrolysis. 



Glucose broth: Colonies on surface cylindrical, white; later flaky mass 

 in bottom of tube. 



Nitrate: Reduction to nitrite. 



Temperature: Optimum 37 °C. 



Antagonistic properties: Positive. 



Remarks: The pigment formed is not soluble. 



100. Streptomyces flocculus (Duch6) Waksman and Henrici. (Duche\ 

 J., Les actinomyces du groupe albus, P. Lechevalier, Paris, 1934.) 



Vegetative growth: Velvety surface with cottony or floccose edge. 



Synthetic agar: Growth cream-colored, later covered with white aerial 

 mycelium; no soluble pigment. 



Nutrient agar: Growth cream-colored, later covered with white aerial 

 mycelium; no soluble pigment. 



Potato: Growth punctiform, covered with white aerial mycelium; pig- 

 ment faint, yellowish. 



Gelatin: Growth limited. Liquefaction slow. 



