mycelium, 0.8 to 1.0 micron, forming nu- merous conidia; flaky growth produced on bottom; surface growth becomes covered with a white aerial mycelium; reverse side, brownish red. Synthetic solution: Cream-colored, punc- tiform growth with yellowish aerial myce- lium; no soluble pigment. Peptone solution: Whitish growth that flakes throughout liquid; yellowish pigment. TjTOsine medium: White growth with yellowish reverse; yellowish soluble pig- ment. Milk: Colorless growth becoming covered with whitish aerial mycelium; slow pep- tonization of milk which becomes rose- colored, finally changing to brownish red. Potato: Cream-colored to j-ellowish growth with whitish aerial mycelium; red- dish brown pigmentation of plug. Coagulated serum: Cream-colored growth with whitish aerial mycelium; rapid lique- faction of serum. Distinctive characters : Abundant growth upon neutral and acid media; whitish aerial mycelium; marked odor; soluble brownish red pigment. Relationships to other species : This spe- cies seems to form the transition type be- tween the Streptomyces albus group and the Streptomyces chrotnogenes group. Source: Isolated from manure. Habitat: Found abundantly in manure. 37. Streptomyces felleus Lindenbein, 1952. (Streptomyces felleus Brockmann and Henkel {nornen nudum), Chem. Ber., 84, 1951, 284; Lindenbein, Arch. f. Mikrobiol., 17, 1952, 374.) fel'le.us. L. adj. felleus of gall, like gall. Aerial mycelium: Hyphae long, straight, branching. Spores spherical. Gelatin: Colorless growth. No aerial my- celium. No soluble pigment. No liquefac- tion. Agar: Colorless diffuse growth with brownish yellow reverse. No aerial myce- lium. Soluble light brownish yellow pig- ment. Synthetic agar: Effused, smooth growth with yellow-brown reverse. Aerial mj^celium velvety gray -white. Soluble yellowish brown pigment. Ca-malate agar: Crumb-like, colorless to yellowish growth. Aerial mycelium pow- dery gray-white. Soluble 3'ellowish brown pigment. Glucose asparagine agar: Thin, colorless growth with j'ellowish reverse. Aerial my- celium powdery gray-white. Soluble brown- ish pigment. Starch agar: Lichenoid, colorless growth. Aerial mycelium powdery white. No solu- l)le pigment. Glucose agar: Effused, crumb-like, j-el- lowish brown growth. Aerial mycelium powdery graj'-white. Soluble light brown pigment. Glucose broth: Fine sediment with some flakes; later a colorless ring on surface. No aerial mycelium and no soluble pigment. Milk: Brownish to orange growth. Aerial mycelium velvety gray-white. Peptonized. Potato: Heavy, brownish yellow growth. Aerial mycelium powdery. Faint reddish pigment around growth. Starch is actively hydrolyzed. No growth on cellulose. Odor: Typical earthy. Antagonistic properties: Produces picro- mycin. Source: Isolated from soil. Habitat: Soil. 38. Streptomyces achromogenes Ok- ami and Umezawa, 1953. (Okami and Ume- zawa, in Umezawa, Takeuchi, Okami and Tazaki, Jap. Jour, of Med. Sci. and Biol., 6, 1953, 266.) a.chro.mo'ge.nes. Gr. adj. achromus colorless; Gr. v. gennaio to produce; M.L. adj . achromogenes producing no color. Aerial mj'celium: Fine branching aerial hj'phae, no spirals. Spores cylindrical. Gelatin: Yellowish brown, restricted growth. No aerial mycelium. Soluble, slightly brown pigment. Yevy weak lique- faction. Agar: Wrinkled, elevated, colorless to brownish growth. No aerial mycelium. No soluble pigment. Glucose asparagine agar: Yellowish brown, restricted growth with brown re- verse. Scant yellowish white aerial myce- lium. Slightly brown soluble pigment may be weakly produced.
