to 2.0 microns, with rounded ends. Oc- casionally coccobacillary. Granulations de- monstrable with methylene blue stain. An- gular and pallisade arrangements of cell masses are typical. Non-motile. Gram- positive. Gelatin stab: No liquefaction. Milk agar: Surface colonies are smooth, convex, entire, pearl-gray and finely amor- phous; 0.5 to 1.5 mm in diameter after 3 days at 32° C. Agar slant: Pearl-gray to pale greenish yellow pigment. Grows as a thin butyrous film, occasionally firmly adherent. Litmus milk weakly acid; occasionally acid coagulation. Indole not produced. Hydrogen sulfide not produced. Acid but no gas from glucose, fructose, mannose, galactose, maltose and lactose. No acid from melibiose, glycerol or dulcitol. Starch hydrolyzed. Non-lipolytic. Ammonia not produced from peptone or arginine. Catalase-positive. Survives 72° C. for 30 minutes in skim milk. Comment: Doetsch and Rakosky (Proc. 50th Gen. Meeting Soc. Amer. Bact., Balti- more, 1950, 38) report a gelatin-liquefying variety of this species. Source: Isolated from pasteurized milk. non-fat dry milk solids, cheese and dairy utensils. 2. Microbacterium flavuin Orla-Jensen, 1919. (The Lactic Acid Bacteria, 1919, 181.) fla'vum. L. adj. flavus yellow. Rods, 0.7 to 0.9 by 1.0 to 3.0 microns, with rounded ends. Non-motile. Granulations demonstrable with methylene blue stain. Gram-positive. Gelatin stab: No liquefaction. Milk agar: Surface colonies are smooth, convex, entire, cream to canary -yellow; 2 to 3 mm in diameter after 3 days at 32° C. Agar-slant: Cream to canary-yellow pig- ment. Growth moderate to heavy, butyrous but occasionally adherent. Litmus milk: No change or slight reduc- tion. Indole not produced. Hydrogen sulfide not produced. Acid but no gas from glucose, fructose or mannose. No acid from maltose, lactose or dextrin. Starch not hydroh'zed. Non-lipolytic. Ammonia not produced from peptone or arginine. Catalase-positive. Survives 72° C. for 15 minutes in skim milk. Source: Isolated from cheese and butter. Under conditions used by several workers in recent extensive investigations, occur- rence reported as rare. Genus V. Cellulomonas Bergey et al., 1923, emend. Clark, 1952.* (Bergey et al.. Manual, 1st ed., 1923, 154; Clark, Internat. Bull. Bact. Nomen. and Taxon., 2, 1952, 50.) Cel.lu.lo.mo'nas. M.L. noun cellulosa cellulose; Gr. noun inonas a unit, monad; INI. L. fem.n. Cellulomonas cellulose monad. Small, pleomorphic rods, straight to angular or slightly curved with occasional beaded, clubbed, branched or coccoid cells, the number of such cells depending on the age and con- dition of the subculture. Motile bj' means of one or a few peritrichous flagella; some species are non-motile. If only a single flagellum is present, it is usually polar. Gram-variable. Growth on ordinary culture media often not vigorous; otherwise, growth on solid media usually soft and smooth and, in broth, turbid. Yellow, non-water-soluble pigmentation common; other pigments also occur. Gelatin slowly hydrolyzed. Catalase-positive. Acid but no gas from carbohydrates; cellulose commonly attacked. Typically of soil or plant origin. The type species is Cellulomonas biazotea (Kellerman et al.) Bergey et al.
- Completely revised by Dr. Francis E. Clark, Agricultural Research Service, Soil Re-
search Branch, U. S. Dept. Agr., Beltsville, Maryland, January, 1954,
