myces 161, Waksman, Soil Sci., 8, 1919, 112; Actinomyces erythreus (sic) Waksman, in Manual, 1st ed., 1923, 370; Streptomyces erythreus (sic) Waksman and Henrici, in Manual, 6th ed., 1948, 938.) e.ryth'rae.us. Gr. adj. erythraeus red. Vegetative growth: Growth spreading, with irregular margin, developing deep into the medium. Color at first white, later turn- ing yellowish, agar around growth has a white, milky surface. Aerial mycelium: Fine, branching; nu- merous open spirals formed as side branches of the main hyphae. Gelatin stab: Abundant, dense, gray growth with pinkish tinge, chiefly on surface of liquefied medium. Agar: Cream-colored growth. Synthetic agar: Spreading growth with irregular margin, developing deep into the medium; color at first white, later turning yellowish; agar around growth has a white, milky surface. Aerial mycelium thick, solid, white. Starch agar: Cream-colored, circular colonies, with faint greenish tinge. Glucose agar: Abundant, spreading, cream-colored growth, later turning brown chiefly on surface; center raised, lobate margin. Glucose broth: Abundant, cream-colored surface growth. Litmus milk: Yellowish surface zone; co- agulated; peptonized, becoming alkaline. Potato: Wrinkled, cream-colored growth, becoming yellowish. Starch is hydrolyzed. Soluble purple pigment formed. Nitrites produced from nitrates. Aerobic. Optimum temperature, 25° C. Antagonistic properties: Marked. Pro- duces erythromycin. Distinctive character: Similar to Strep- tomyces erythrochromogenes except that no brown soluble pigment is formed. Source: Isolated from Californian and Hawaiian soils. Habitat: Soil. 33. Streptomyces flavogriseus (Duche, 1934) Waksman, 1953. (Actinomyces flavo- griseus Duch6, Encyclop^die Mycologique, Paris, 6, 1934, 341; Waksman, in Waksman and Lechevalier, Actinomycetes and Their Antibiotics, Baltimore, 1953, 55.) fla.vo.gri'se.us. L. adj. flamis yellow; M.L. adj. griseus gray ; M.L. iidj. flavogriseus yellowish gray. Aerial mvcelium: Long, straight hj'phae producing a few curling tips. Spores spher- ical. Gelatin: Plocculent growth throughout medium. No soluble pigment. Slow liquefac- tion. Agar: Thin, cream-colored growth. Aerial mycelium thin, white. No soluble pigment. Synthetic agar: Limited, yellowish growth with reverse turning black. Aerial mycelium thin, gray to mouse-gray. Glucose peptone agar: Yellow surface growth with reverse tending to turn dark. Aerial mycelium abundant, mouse-gray to drab. No soluble pigment. Starch agar: Very limited growth. Similar to that on sj'nthetic agar. Broth: Cream-colored surface growth in clumps. Aerial mycelium gray. Milk: Cream-colored ring. No aerial mycelium. Very rapid peptonization. Potato: Abundant, lichenoid growth. Abundant aerial mycelium, mouse-gray to drab with white edge. No soluble pigment. Starch is hydrolyzed. Source: Isolated from volcanic soils in Martinique. Habitat: Presumabl}' soil. 34. Streptomyces diastaticus (Krain- sky, 1914) Waksman and Henrici, 1948. (Actinomyces diastaticus Krainsky, Cent. f. Bakt., II Abt., 4i, 1914, 662; also see Waks- man and Curtis, Soil Sci., i, 1916, 116; Waks- man and Henrici, in Manual, 6th ed., 1948, 939.) di.a.sta'ti.cus. Gr. adj. diastaticus sep- arative; M.L. n. diastasum the enzyme di- astase, hence M.L. adj. diastaticus diastatic, starch-digesting. Aerial mycelium: Filaments may show fine, long, narrow spirals. Conidia ellip- soidal, 1.0 to 1.2 by 1.1 to 1.5 microns. Gelatin stab: Liquefaction with small, cream-colored flakes in liquid.
