182 



ORDER I. PSEUDOMONADALES 



10. Pseudomonas pictorum Gray and 

 Thornton, 1928. (Cent. f. Bakt., II Abt., 73, 

 1928, 89.) 



pic.to'rum. Named for the Picts, a Scot- 

 tish tribe; M.L. neut.pl. gen. n. 'pictorum of 

 the Picts. 



Rods 0.5 to 0.8 by 1.5 to 5.0 microns. 

 Motile, usually with a single polar flagel- 

 lum. Gram-negative. 



Gelatin colonies: Circular, greenish 

 yellow, convex, smooth, glistening, entire. 



Gelatin stab: No liquefaction. 



Agar colonies: Circular, yellow, conve.x, 

 smooth, glistening, entire. 



Agar slant: Filiform, yellow, convex, 

 smooth, glistening, entire. 



Broth: Turbid. 



Nitrites produced from nitrates. 



Starch not hydrolyzed. 



Acid from glucose and maltose. 



Attacks phenol. 



Aerobic, facultative. 



Optimum temperature, 25°C. 



Source: One culture from soil. 



Habitat: Soil. 



11. Pseudomonas argiita McBeth, 1916. 

 (Soil Science, 1, 1916, 465.) 



ar.gu'ta. L. part. adj. argutus clear, 

 bright. 



Rods 0.3 by 0.8 micron. Motile with one 

 or two polar flagella. Gram-negative. 



Gelatin stab : Moderate, yellowish growth. 

 No liquefaction in 30 daj^s. 



Agar colonies: Circular, slightly convex, 

 soft, grayish white, granular, entire. 



Agar slant: Scant, grayish white growth. 



Potato agar slant: Moderate, yellowish, 

 glistening growth. 



Broth: Turbid. 



Ammonia cellulose agar: Enzymatic zone 

 2 to 3 mm in 30 days. 



Filter paper broth: Paper is reduced to 

 loose flocculent mass which disintegrates 

 very readily on slight agitation. More rapid 

 decomposition when the broth contains 

 ammonium sulfate, potassium nitrate, pep- 

 tone or casein as source of nitrogen. 



Litmus milk: Acid, not digested. 



Potato: No growth. 



Indole not produced. 



Nitrites produced from nitrates. 



Ammonia not produced. 



Acid from glucose, maltose, lactose and 

 starch. No acid from glycerol, mannitol or 

 sucrose. 



Aerobic, facultative. 



Optimum temperature, 20° C. 



Source: Isolated twice from California 

 soils. 



Habitat: Soil. 



12. Pseudomonas subcreta McBeth and 

 Scales, 1913. (Bur. Plant Industry, U. S. 

 Dept. Agr., Bull. 266, 1913, 37.) 



sub.cre'ta. L. pref. sub- somewhat; L. 

 creta chalk; M.L. adj. subcretus somewhat 

 chalky. 



Rods 0.3 by 1.4 microns. Motile with one 

 to five polar flagella. Gram-negative. 



Gelatin stab: Filiform growth, no lique- 

 faction. 



Cellulose agar: No surface growth. 

 Moderate, generally faint yellow growth 

 in medium, area of growth sunken. 



Agar slant: Glistening, smooth, moist, 

 vitreous to faint yellow growth. 



Starch agar: Enzymatic zone 2 to 4 mm. 



Broth: No growth. 



Litmus milk: No growth. 



Potato: Growth scant, concave due to 

 slight liquefaction, white to faint yellow. 

 Bleached around growth. 



Indole not produced. 



Trace of nitrites produced from nitrates. 



Ammonia not produced. 



Acid from glucose, lactose, maltose, 

 sucrose and starch. No acid from glycerol 

 or mannitol. 



Aerobic, facultative. 



Optimum temperature, 20° C. 



Habitat: Soil. 



13. Pseudomonas lacunogenes Gores- 

 line, 1933. (Jour. Bact., £6, 1933, 447.) 



la.cu.no'ge.nes. L. lacuna a hollow; L. 

 gicjno to produce; M.L. adj. lacunogenes pro- 

 ducing hollows. 



Short rods, 0.2 to 0.3 by 1.0 to 1.2 microns, 

 with pointed ends, occurring singly or in 

 pairs. Motile with a single polar flagellum 

 from 2 to 15 microns in length. Gram-nega- 

 tive. 



Plain gelatin stab: No growth. 



Nutrient gelatin stab: Growth brownish 

 yellow, half-way down stab, heavier at 

 surface. No liquefaction. 



