folded, pale-yellow, surface colony. No liquefaction. Glucose-asparagine-agar: Fair growth, narrow, raised, granular, very pale j-ellow, glistening; condensation water clear, with small granules. At 30° C. there is only scant growth consisting of small, irregular, white granules growing deeply down into the agar. Glucose-nutrient-agar: Good growth, re- stricted, with undulate edges, surface with high transverse folds, cream-colored; the consistency^ is firm and cartilaginous after 2 days, later looser and more brittle. Growth at 28° to 30° C. rather scant; smooth, soft, glistening, cream-colored smear. Sabouraud's agar: Excellent growth, spreading, at first flat and smooth, pale straw-yellow, perfectly hard and cartilagi- nous, later raised and strongly folded, of a loose, curd-like consistency, bright lemon- yellow. Growth at 28° to 30° C. only fair, restricted, folded, cream-colored, soon be- coming soft and smeary. Broth: Good growth; voluminous, flaky, whitish sediment; broth clear. Potato: Scant growth; restricted, soft, cream-colored smear. Milk: At 28° to 30° C., small cream- colored granules along the tube; the milk undergoes no visible changes within 4 weeks. No proteolytic action. Indole not produced. Sucrose is inverted. Starch is hydrolyzed. Cellulose not decomposed. Nitrites produced from nitrates. No growth in oxygen-free atmosphere. Nitrogen is utilized as sodium nitrate, ammonium phosphate and asparagine, al- though these are inferior to peptone as sources of nitrogen. Source: Isolated from fermented beets. Habitat: Found in fermented vegetable materials. 21. Nocardia albicans (Krassilnikov, 1941) Waksman, 1953. {Proactinomyces albi- cans Krassilnikov, Guide to the Actino- mycetes, Izd. Akad. Nauk, U.S.S.R., Moskau, 1941, 71; Waksman, in Waksman and Lechevalier, Actinomycetes and Their Antibiotics, Baltimore, 1953, 146.) al'bi.cans. L. part. adj. albicans white- making. On solid media the hj'phae break up into rod-shaped cells 0.6 to 0.7 by 12 to 25, some- times up to 50, microns. Cells straight or slightly curved and branching. No aerial mycelium observed except surface layer of sporophores, which produce a velvety ap- pearance. Multiplication is by fission, seldom by budding. Gram-positive. Gelatin: No liquefaction. Agar colonies: Smooth, shiny; good growth. Broth: Poor growth; faintly turbid; settles on bottom and leaves a surface ring. No true mycelium produced. Cells rod- shaped, 5 to 10, seldom 15 to 20, microns. Milk: No change. Sucrose inverted. Starch hydrolyzed. No growth on cellulose. Utilizes glycerol well but not paraffin. Nitrites not produced from nitrates. Nitrate utilized as a source of nitrogen. Source: Isolated from soil. Habitat: Soil. 22. Nocardia flava (Krassilnikov, 1938) Waksman and Henrici, 1948. (Proactino- myces flavus Krassilnikov, Bull. Acad. Sci. U.S.S.R., No. 1, 1938, 139; Waksman and Henrici, in Manual, 6th ed., 1948, 908.) fla'va. L. adj. flavus yellow. Cells at first filamentous, 0.7 to 0.8 mi- cron in diameter; after 2 to 3 days, cells broken into long rods and then into cocci 0.7 micron in diameter. No spores, although some strains form chlamydospores. Cell multiplication is by fission, cross-wall for- mation and rarely by budding. Not acid- fast. Gram -positive. Gelatin: No liquefaction. Agar colonies : Pigment bright yellow or gold-colored on synthetic media, dirty yellow on meat peptone media. Pigment not soluble in medium. Surface of colony somewhat shiny or rough and folded, of a dough-like consistency. Synthetic agar colonies: Bright yellow or gold. Meat peptone media: Dirty j-ellow pig- mentation. Milk: No peptonization or coagulation.
