CLASSIFICATION OF THE ACTINOMYCETES 37 



A. Aerial mycelium white; no soluble pigment. 



Thermoactinomyces vulgaris 



B. Aerial mycelium grayish green. 



Thermoactinomyces monospora 



C. Aerial mycelium white; soluble wine-colored to rose pigment in certain 

 media Thermoactinomyces thalpophilus 



The Genus Actinomyces 



Although no antibiotics have so far been demonstrated for members of 

 the genus Actinomyces, this group is included to make the guide to the 

 actinomycetes complete. 



The genus Actinomyces comprises anaerobic or microaerophilic organisms; 

 mostly parasitic. Nonparasitic forms have been insufficiently studied. The 

 species are non-acid-fast, nonproteolytic, and nondiastatic. 



1. Colonies soft, smooth, uniform, not adherent to medium; no 

 aerial hyphae. .Actinomyces bovis 



2. Colonies tougher in texture and warted in appearance, adherent 

 to medium; scanty aerial growth of hyphae. 



Actinomyces israeli. 



