FAMILY III. STREPTOMYCETACEAE 747 



9. Growth cream-colored to yellowish to red; aerial mycelium white to gray, 

 a^ Growth becoming red; aerial mycelium white. 



32. Sirepiomyces erythraeus . 



a^. Growth yellow; aerial mycelium mouse-gray to drab. 



33. Stre-ptomyces fiavogriseus . 



10. Soluble pigment on potato plug brown to brownish red to reddish purple, 

 a^ Growth on potato greenish-colored; spirals formed. 



34. Streptomyces diastaticus. 

 a^. Growth on potato gray; no spirals formed. 



35. Streptomyces canescens. 

 a'. Growth on potato yellowish-colored. 



b'. Greenish tinge produced. 



36. Streptomyces fimicarius. 

 h^. Pigment reddish brown. 



37. Streptomyces felleus. 



b'. Soluble brown pigment on synthetic agar. 



38. Streptomyces achromogenes . 



a^. Growth on potato pink to reddish purple; spirals produced. 



39. Streptomyces noursei. 

 B. Soluble pigment on organic media brown. 



1. Pigment deep brown (chromogenic types). 



a^ Aerial mycelium thin, rose-colored, 

 bi. Spirals produced. 



40. Streptomyces roseochromogenes . 

 b^. No spirals formed. 



41. Streptomyces cinnamonensis . 

 a?. Aerial mycelium gray to brown to reddish. 



bi. Growth on organic media greenish to black. 



42. Streptomyces olivochromogenes. 

 h^. Growth dark brown. 



43. Streptomyces resistomycificus . 



a^. Aerial mycelium cottony, dark brown; rapid liquefaction of 

 gelatin. 



44. Streptomyces diastatochromogenes. 

 &*. Colonies yellow; aerial mycelium white to gray. 



45. Streptomyces flavochromogenes . 



a^. Growth white to gray; aerial mycelium white to gray. 



46. Streptomyces hikiniensis. 



a^ Growth white, fluffy; sporulating hyphae straight. 



47. Streptomyces mirahilis. 



aJ. Growth cream-colored to brown; aerial mycelium gray; sporo- 

 phores in clusters. 



48. Streptomyces antihioticus . 



a^. Aerial mycelium white, turning light pink on certain media; 

 sporophores straight, no spirals. 



49. Streptomyces griseocarneus. 



a^ Aerial mycelium greenish yellow, turning gray; sporophores 

 produced in tufts or whorls. 



50. Streptomyces viridoflavus . 



2. Growth on synthetic agar dark brown. 



a^ Aerial mycelium dark gray; spores globose. 



51. Streptomyces globosus. 



