cus indicus Koch, Berichte ueber die Reise zur Erforschung der Cholera, 1887; Bergey et al.. Manual, 1st ed., 1923, 88; Breed and Breed, Jour. Bact., 11, 1926, 76.) in'di.ca. L. adj. indicus pertaining to In- dia. Small rods, 0.5 by 1.0 to 1.5 microns. Mo- tile by means of four peritrichous flagella. Gram-negative. Gelatin colonies: Resemble those of Ser- ratia viarcescens Bizio. Gelatin stab: Liquefaction occurs rather quickly. Brilliant orange-red pellicle on plain gelatin. Agar colonies: Pink, slightly serrate, spreading, with green iridescence. Agar slant: Lu.xuriant, dirty white layer. Pigment produced best in alkaline media. Broth: Turbid, white sediment. Litmus milk: Acid and coagulated. Diges- tion complete in 10 days. Potato : Lu.xuriant growth with or without pigment production. Indole not produced. Produces same products (except Ho) from glucose as does Serratia viarcescens (Peder- son and Breed, Jour. Bact., 16, 1928, 183). Growth with pigment production in dis- tilled water containing urea, potassium chloride and glucose. Acetylmethylcarbinol is produced (Breed). Nitrites produced from nitrates. Coagulated blood serum is liquefied. Odor of trimethylamine is produced. Sodium formate broth: Cultures do not produce visible gas (Breed). Aerobic, facultatively anaerobic. Optimum temperature, between 25° and 35° C. No growth at 37° C. Pathogenic for laboratory animals. Comment : A non-gelatin-liquefying strain of this species has been reported (see Breed, in Manual, 6th ed., 1948, 481). Relationship to other species : Cultures of this organism lo.se their ability to produce the orange-red pellicle on gelatin and then become practically indistinguishable from cultures of Serratia marcescens. This would indicate that this so-called species is a rough strain of the former species (Breed). See Reed (Jour. Bact., 34, 1937, 255) for a discussion of dissociation phenomena in this genus. Source: Isolated from the alimentary tract of a Java ape in India; also from a milk can from Ithaca, N. Y. Habitat: Presumably widely distributed. Not common. 3. Serratia plymuthica (Lehmann and Neumann, 1896) Bergey et al., 1923. (Roter Bacillus aus Plymouth, Fischer, Ztschr. f. Hyg., 2, 1887, 74; Bacterium -plymuthicum Lehmann and Neumann, Bakt. Diag., 1 Aufl., 2, 1896, 264; Bergey et al., Manual, 1st ed., 1923, 88.) ply.mu'thi.ca. M.L. adj. plymuihicus per- taining to Plymouth. Distinct rods, 0.6 by 1.5 to 2.0 microns, with rounded ends, occurring singly and in short chains. Motile by means of peritri- chous flagella. Gram-negative. Gelatin colonies: Like those of Serratia marcescens Bizio. Original culture mucoid. Gelatin stab: Crateriform liquefaction. Liquefaction as in Serratia marcescens. Agar colonies: Like mucoid variants of Serratia marcescens. Agar slant: Sometimes show metallic luster. Pigment as in Serratia marcescens. Broth: Growth like that of Serratia mar- cescens. Litmus milk: Acid and coagulated. Potato: Growth violet-pink, with or with out metallic luster. Strong fecal odor produced. Gas from glucose, lactose and sucrose, 70 to 80 per cent of it being CO2 , the remainder is H2 . Gas is also produced in asparagine solutions. Acetylmethylcarbinol is produced (Breed). Sodium formate broth: Cultures produce abundant gas (Breed). Coagulated blood serum is liquefied. Pigment is soluble in alcohol and ether and sometimes slightly so in water. Aerobic, facultatively anaerobic. Optimum temperature, 30° C. Source: Isolated from the water supply of Plymouth, England. Habitat: Found in water and in various foods.
