SPECIES OP STREPTOMYCES 115 



Synthetic glucose agar: Growth fairly rough, pale gray; aerial mycelium 

 scant, white. Soluble pigment yellowish to pink. 



Nutrient potato agar: Growth granular, gray; aerial mycelium abundant, 

 white to olive-buff. Soluble pigment light golden brown. 



Potato: Growth poor, wrinkled, grayish vinaceous; aerial mycelium white 

 to grayish vinaceous. Plug colored brown around and below growth. 



Gelatin: Growth limited, gray; aerial mycelium scant, white. Liquefac- 

 tion rapid. 



Milk: Surface growth good, covered with abundant white aerial myce- 

 lium. Coagulation; peptonization rapid. 



Starch: No hydrolysis. 



Glucose broth: Minute compact colonies at bottom and on surface. Aerial 

 mycelium scant, white. 



Nitrate: No reduction. 



Glycerol synthetic solution: No growth. 



Tyrosinase reaction : Negative. 



Temperature: Does not grow at 37.5°C. 



Habitat: Grass compost. 



133. Streptomyces sampsonii (Millard and Burr) comb. nov. (Millard, 

 W. A., and Burr, S., Ann. Appl. Biol., IS, 1926, 580.) 



Aerial mycelium: Long branching aerial hyphae. Spores cylindrical, 0.8- 

 1.0 by 0.5 ij. (spores oval to spherical, WG*). 



Synthetic sucrose agar: Growth good, wrinkled, pale gray to white. Aerial 

 mycelium very scant, white. Soluble pigment green to buff. 



Synthetic glucose agar: Growth good, wrinkled, white to gray. Aerial 

 mycelium scant, white. Soluble pigment yellow to brownish. 



Potato: Growth wrinkled, grayish. Aerial mycelium white. Soluble pig- 

 ment golden brown (none, WG) . 



Gelatin: Surface growth scant, gray. Aerial mycelium trace of whitish. 

 Liquefaction rapid. 



Milk: Surface growth good, whitish. No aerial mycelium. No coagulation; 

 no peptonization (peptonization rapid, WG.) 



Starch: No hydrolysis (rapid hydrolysis, WG). 



Glucose broth: Good surface and bottom growth, as well as many colonies 

 clinging to side of tube. Aerial mycelium white. 



Nitrate: Reduction. 



Glycerol synthetic solution: No growth. 



Tyrosinase reaction: Negative. 



Temperature: 28°C. 



Habitat: Potato scab. 



* WG = Observation made in our laboratory by Waksman and Gordon. 



