362 



ORDER IV. EUBACTERIALES 



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. 



