chromogenesis; nailhead growth in gelatin stab; branching rods and short filaments. Source : Seventy-four strains were isolated from soils in Great Britain and Australia. Habitat: Soil. 14. Nocardia globerula (Gray, 1928) Waksman and Henrici, 1948. {Mycobacterium globendum Gray, Proc. Roy. Soc. London, B, 102, 1928, 265; Proactinomijces globerulus Reed, in Manual, 5th ed., 1939, 838; Waks- man and Henrici, in Manual, 6th ed., 1948, 903.) glo.be'ru.la. L. noun globus a globe; M.L. dim. adj. globerulus globular. Original description supplemented by material taken from Bynoe (Thesis, McGill University, Montreal, 1931). Curved rods and filaments, 1 by 2 to 9 microns, with many coccoid cells, especially in old cultures. Rods and filaments are fre- quently irregularly swollen. Capsules may be present. Not acid-fast. Gram-positive. Gelatin: After 19 days, surface colonies irregularly round, 1 to 2 mm in diameter, conve.x, light buff, smooth, shining; edge entire. Deep colonies: Round, with entire edge. Gelatin stab: After 8 days, nailhead, ir- regularly round, convex, pinkish white, smooth, shining growth; line of stab erose. Agar: After 4 days surface colonies irregu- larly round, 3 to 5 mm in diameter, convex, white, smooth, shining; edge undulate, erose. After 7 daj^s, more convex and of a watery appearance. Deep colonies: After 4 days, lens-shaped. Agar slant: After 3 days, filiform, flat, watery; edge irregular. Dorset's egg medium: After 2 weeks, spreading, raised, moist, orange-colored growth. Loefller's medium: Growth as on Dorset's egg medium, but salmon-colored. Nutrient and peptone broth: Turbid with viscous suspension. Litmus milk: Alkaline. Glycerol potato: After 24 hours, filiform, moist, smooth, pale pink growth. Indole not produced. Indole agar: Blue crystals of indigotin formed. No acid from glucose, lactose, maltose, sucrose or glycerol. Phenol is utilized. Nitrites not produced from nitrates. Optimum temperature, between 25° and 28° C. Optimum pH, between 6.8 and 7.6. Distinctive characters: This organism re- sembles most closely Nocardia coralUna. It is distinguished by producing a more watery type of surface growth, more nearly entire deep colonies and more particularly by the production of indigotin from indole. Source: Isolated from soil in Great Britain. Habitat: Presumably soil. 15. Nocardia salmonicolor (den Dooren de Jong, 1927) Waksman and Henrici, 1948. {Mycobacterium salmonicolor den Dooren de Jong, Cent. f. Bakt., II Abt., 71, 1927, 216; Proactinomyces salmonicolor Jensen, Proc. Linn. Soc. New So. Wales, 57, 1932, 368; Waksman and Henrici, in Manual, 6th ed., 1948, 904; also see Erikson, Jour. Gen. Microbiol., S, 1949, 364.) sal.mo.ni'co.lor. L. noun salmo salmon; L. gen. noun salmonis of a salmon; M.L. adj. salmonicolor salmon-colored. On glucose-asparagine-agar after 18 to 24 hrs., long branching rods are formed, 1.0 to 1.3 microns in diameter, with small refrac- tive granules of aerial mycelium, sometimes stretching into quite long filaments; after 2 to 3 days small definite mycelia are pres- ent, and after 5 to 6 days these have largely divided into short rods and cocci; the col- onies have the same burr-like appearance as those of Nocardia corallina. Many cells at the edge of the colonies show, after 3 to 4 days, club- or pear-shaped swellings, up to 2.5 to 3.0 microns in diameter; after 5 to 6 days, many of these swollen cells are seen to germinate with the formation of two more slender sprouts. On some media a few short, undivided aerial hyphae appear which may actually form a thin white frosting over the pink growth. Acid-fastness is found among the earlier stages of growth in some of the strains on some media. Gelatin: At 20° to 22° C, scant, arbores- cent growth in stab; small, wrinkled orange, surface colony. No liquefaction.
