white powdery aerial mycelium; later abundant, raised, pale pink, confluent growth, discolored plug; after 2 months, raised, buckled, pink colonies with white aerial mycelium floating on liquid at base. Source: Isolated from infected guinea pigs in Sumatra. Habitat: Unknown. 32. Nocardia actinomorpha (Gray and Thornton, 1928) Waksman and Henrici, 1948. {Mycobacterium actinomorphum Gray and Thornton, Cent. f. Bakt., II Abt., 73, 1928, 88; Proactinomyces actinomorphus Jensen, Proc. Linn. Soc. New So. Wales, 56, 1931, 363; Waksman and Henrici, in Manual, 6th ed., 1948, 912.) ac.ti.no.mor'pha. Gr. noun actis, actinis a ray; Gr. noun morphe shape; M.L. adj. actinomorphus ray-shaped. Original description supplemented by ma- terial taken from Jensen {op. cit., 1931, 363) and Bynoe (Thesis, McGill University, Montreal, 1931). Long branching filaments and rods, 0.5 to 0.8 by up to 10 microns. In older cultures rods 2 to 3 microns long generally predomi- nate. On some media, extensively branch- ing hyphae occur. Readily stained. Not acid-fast. Gram-positive. Gelatin colonies: After 12 daj^s, round, saucer-like, white, raised rim, edges burred. Deep colonies: Burrs. Liquefaction. Gelatin stab: After 8 to 14 days, saccate liquefaction, 5 to 8 mm. Agar colonies: After 11 days, round, 1 mm in diameter, convex, white, granular or resinous; long, arborescent processes from the edge. Deep colonies: Arborescent burrs; processes about equal to diameter of colony. Agar slant: Filiform, raised to convex, white, rugose, dull growth; edge undulate, with strong tufted projections below sur- face. Broth: Turbid or clear with white scum. Dorset's egg medium: After 2 weeks, raised, dry, smooth, salmon-buff growth. Loeffler's medium: After 2 days, smooth, moist, warty, salmon-colored growth. Litmus milk: Alkaline after 5 to 7 days. Glycerol potato: After 2 days, dry, wrinkled, pink to orange growth. No acid from glucose, lactose, sucrose or glycerol. Nitrites produced from nitrates. Phenol and naphthalene are utilized. Optimum temperature, between 25° and 30° C. Optimum pH, between 7.8 and 8.5. Distinctive characters: Differs from No- cardia coeliaca in saccate liquefaction of gelatin. Long rods and filaments. Source: A few strains have been isolated from soil in Great Britain and Australia. Habitat: Presumably soil. 33. Nocardia alba (Krassilnikov, 1938) Waksman, 1953. {Proactinomyces albus 'Kras- silnikov, Bull. Acad. Sci., U.S.S.R., No. 1, 1938, 139; Waksman, in Waksman and Lechevalier, Actinomycetes and Their Anti- biotics, Baltimore, 1953, 153.) al'ba. L. adj. albus white. Colonies white, never pigmented, of dough-like consistency; smooth or folded growth; shiny or pale. True substrate my- celium produced at first, then breaking up into short rods, 0.7 to 0.8 by 2.7 microns, later changing into a mass of coccus-like cells, 0.7 to 1.0 micron in diameter. Many cells are swollen, others form side buds. No aerial mycelium produced on nutrient media. Not acid-fast. Gram-positive. Gelatin: Liquefaction. Agar: Good growth. Synthetic agar: Inorganic sources of nitrogen are used, and sugar, starch or or- ganic acids serve as sources of carbon. Milk: Coagulated and peptonized. Sucrose inverted. Starch rapidly hydrolyzed. Cellulose: No growth. Nitrites not produced from nitrates. Comment: Krassilnikov {op. cit., 1941, 73) recognizes several subspecies. Source: Isolated from soil. Habitat: Soil. 34. Nocardia flavescens (Jensen, 1931) Waksman and Henrici, 1948. {Proactino- myces flavescens Jensen, Proc. Linn. Soc. New So. Wales, 56, 1931, 361; Waksman and Henrici, in Manual, 6th ed., 1948, 913.)
