Milk agar streak plate: Usually scant, if any, hydrolysis of the casein. Potato: Usually no visible growth. Vari- ations : Growth scant to abundant, yellowish to brownish. GummJ^ Indole not produced. Acid but no gas (with ammonium salts as source of nitrogen) from glucose; acid usually produced from arabinose, xylose and sucrose. Starch is hydrolyzed. Crystalline dextrins produced from starch by some strains. Acetylmethylcarbinol not produced. pH of glucose broth cultures is usually less than 5.5. Citrates usually not utilized. Methylene blue usuall}^ reduced; reox- idized in few days. Nitrites may or may not be produced from nitrates. Usually no gas produced in nitrate broth under anaerobic conditions. Urease usually not produced. Thiamine and biotin are essential for growth. Lecithinase not produced. Aerobic, usually facultatively anaerobic. Usually there is growth in glucose broth under anaerobic conditions, pH 4.8 to 6.0. Temperature relations: Optimum, about 30° C. Maximum, usually between 40° and 45° C; with some strains, between 50° and 55° C. Source: Isolated from tap water. Habitat: Widely distributed in soil, water and dust; also found as a laboratory con- taminant. 17. Bacillus laterosporus Laubach, 1916. (Jour. Bact., 1, 1916, 511.) la.te.ros'po.rus. L. noun latus, lateris the side or flank; Gr. noun sjpora seed;M.L. noun spora a spore; M.L. adj. laterosporus with lateral spore. Rods, 0.5 to 0.8 by 2.0 to 5.0 microns, sometimes slightly smaller or larger in width, with ends poorly rounded or pointed. Motile. Gram- variable. Spores, 1.0 to 1.3 by 1.2 to 1.5 microns, ellipsoidal, central, formed at one side of the rod. Spore wall thick and easily stained. Remnants of sporangium adhering to ma- ture spore thicker on one side of the spore than on the other. Sporangia definitely bulged and spindle- shaped. Gelatin stab: Slow liquefaction. - Gelq,tin agar streak plate: Visible zone of hydrolysis. Agar colonies: Thin, translucent, spread- ing, irregular. Variations: Small, round, rough, opaque. Agar slants: Growth thin, flat, spreading, translucent. Variations: Growth abundant or restricted. Opaque. Glucose agar slants: Growth heavier than on agar, dense and wrinkled. Soybean agar slants: Growth variable.
Broth: Turbidity uniform to granular.
NaCl broth: Usually there is growth in 2 per cent NaCl; no growth in 5 per cent. ' Milk: Usually curdled, peptonized. Milk agar streak plate: Usually there is a wide zone of hydrolysis of the casein. Potato: Growth scant to abundant, spreading, gray, pink or brown. Indole usually produced. n/ Acid but no gas (with ammonium salts as source of nitrogen) from glucose and mannitol; acid usually produced from su- qrose. No acid from arabinose or xylose. J Starch not hydrolyzed. Acetylmethylcarbinol not produced. pH of glucose broth cultures is 6.0 to 7.4. Citrates not utilized. J Nitrites produced from nitrates. Usually a few bubbles are produced in nitrate broth under anaerobic conditions. Urease not produced, s/ Aerobic, facultatively anaerobic. Growth in glucose broth under anaerobic condi- tions, pH 4.8 to 5.8. ^ Temperature relations: Optimum, be- tween 28° and 37° C. No growth at 45° C. Source: Isolated from water. Habitat: Widely distributed in soil, water and dust. 18. Bacillus pulvifaciens Katznelson, 1950. (Jour. Bact., 59, 1950, 153.) pul.vi.fa'ci.ens. L. noun pulvus dust; L. V. facio to make; M.L. part. adj. pulvi- faciens dust-producing. Rods, 0.3 to 0.6 by 1.5 to 3.0 microns,
