80 ACTINOMYCETES 



straight, branching. Spirals formed according to original report (none in 

 our own observation) . Spores spherical . 



Synthetic agar: Growth cream-colored, with trace of brown. Aerial myce- 

 lium heavy cream-colored. 



Nutrient agar: Growth folded, brown. Aerial mycelium white around 

 edge. Faint soluble brown pigment. 



Glucose agar: Growth cream-colored to brownish. Aerial mycelium abun- 

 dant, cream-colored. Soluble pigment faint brownish. 



Potato: Growth folded, brownish. Aerial mycelium cream-colored. Sol- 

 uble pigment faint. 



Gelatin: Surface ring cream-colored. Aerial mycelium thin, white. No sol- 

 uble pigment. Liquefaction slow. 



Milk: Surface ring colorless to brownish. No aerial mycelium. No coagu- 

 lation. Peptonization. 



Starch: Growth cream-colored to brown. Aerial mycelium abundant, 

 cream-colored to straw-colored. No soluble pigment. Hydrolysis good. 



Cellulose: Growth good. 



Nutrient broth: Surface film colorless. Aerial mycelium heavy, cream- 

 colored. No soluble pigment. 



Nitrate: Reduction positive. 



Sucrose: Inversion. 



Paraffin, fats: Growth good. 



Odor : Strong, characteristic of soil. 



Antagonistic properties: Some strains give positive effects, others are 

 negative. 



72. Streptomyces roseoflavus Arai (Arai, T., J. Antibiotics [Japan], 

 4, 1951, 215-221.) 



Vegetative growth: Colonies large, flat; vegetative mycelium limited to 

 medium. 



Aerial mycelium: White to rose-colored, producing numerous spirals. 

 Spores oval to oblong, 0.8-1.0 by 1.0-1.8 ju. 



Synthetic agar: Growth penetrating deep into medium, colorless to yel- 

 lowish ; aerial mycelium powdery, white to yellow-rose. 



Nutrient agar: Growth much-folded, white-gray to golden yellow; aerial 

 mycelium, limited to center of colonies, white to rose-colored. 



Glucose agar: Growth colorless to yellowish white; aerial mycelium rose- 

 colored. 



Potato: Growth yellow mass. No aerial mycelium; no soluble pigment. 



Gelatin : Liquefaction strong. Colonies at bottom of liquefied zone orange- 

 brown. No soluble pigment. 



