170 



THE ACTIXOMYCKTES, V 



Glycerol malate agar: Growth light 

 pinkish-cinnamon. Aerial mycelium late, 

 white. 



Glucose-asparagine agar: Growth re- 

 stricted, much folded, cream-colored with 

 sulfur-yellow surface. No aerial mycelium. 

 No soluble pigment. 



Nutrient agar: Growth restricted, cream- 

 colored. No aerial mycelium. No soluble 

 pigment. 



Potato: Growth wrinkled, moist, cream- 

 colored. 



Gelatin: Surface growth abundant, color- 

 less. Aerial mycelium white or absent. No 

 soluble pigment. Slow liquefaction. 



Milk: Surface ring pinkish. No coagula- 

 tion; limited peptonization. 



Starch media: Growth thin, spreading, 

 yellowish. No aerial mycelium. Good hy- 

 drolysis of starch. 



Cellulose: Scant growth. 



Nitrate reduction: Positive. 



Production of H 2 S: Negative. 



Temperature: Optimum 37°C. 



Antagonistic properties: Positive. 



Remarks: Various cultures related to this 

 organism have been described under a 

 variety of different names. It is sufficient to 

 mention A. cremeus, A. griseoloalbus, A. 

 flavidovirens, and a variety of the latter, 

 fuscus, described by Gause et al. (1957). 

 Krassilnikov (1949) considered it as a 

 variety of A. flams. 



Type culture: IMRU 3008. 



11. Streptomyces albogriseolus Benedict et 

 al, 1954 (Benedict, R. G., Shotwell, 0. L., 

 Pridham, T. G., Lindenfelser, L. A., and 

 Haynes, W. C. Antibiotics & Chemotherapy 

 4: 653-656, 1954). 



Morphology: Sporophores monopodially 

 branched, producing short, compact spirals, 

 averaging 4 to 6 turns. Spores spherical or 

 oval, covered with numerous long, fine hairs 

 (PI. II n). 



Sucrose nil rate agar: Aerial mycelium 



white, becoming ash-gray, often with white 

 spots. 



Starch agar: Aerial mycelium white to 

 dark gray. Hydrolysis. 



Nutrient agar: Aerial mycelium white to 

 ash-gray. Melanin-negative. 



Potato: Growth cretaceous to dirty gray- 

 ish-white to faint pink. 



Carrot: Vegetative growth white to dirty 

 cream; no aerial mycelium. Slant not dark- 

 ened. 



Gelatin: Dirty white sediment. Positive 

 liquefaction. Not pigmented. 



Milk: Orange-colored ring; partially pep- 

 tonized at 14 days. 



Nitrate: Reduction to nitrite. 



Production of H 2 S: Negative. 



Temperature: Good growth at 25-41°C. 

 No growth at 50°C. 



Antagonistic properties: Produces a "neo- 

 mycin complex." 



Habitat: Soil. 



Type culture: IMRU 3698. 



12. Streptomyces alboniger Hesseltine et al., 

 1954 (Hesseltine, C. W., Porter, J. N., 

 Deduck, N., Hawk, M., Bohonos, N., and 

 Williams, J. H. Mycologia 46: 16-23, 1954). 



Morphology: Sporophores irregularly 

 branched, erect to flexuous; no spirals. Ver- 

 ticils produced. Spores catenulate, oval, 

 0.8 by 1.25 M . 



Sucrose nitrate agar: Growth poor, white. 

 Aerial mycelium white to pale olive-buff. 

 No soluble pigment. 



Glucose-asparagine agar: Growth black- 

 ish-gray. Aerial mycelium white. Soluble 

 pigment blackish-gray. 



Nutrient agar: Growth moist, smooth, 

 colorless to yellowish, to dark brown or 

 black. No aerial mycelium. No soluble 

 pigment. 



Starch agar: Growth good. Aerial my- 

 celium white to pale olive-buff. Soluble 

 pigment black. Good hydrolysis. 



Potato: Growth moist, yellow. Aerial 



