FAMILY VI. BACTEROIDACEAE 



445 



Source: Two strains were isolated from 

 human feces. 



Habitat: Probably the intestinal canals of 

 mammals. 



4. Sphaerophorus siccus (Eggerth and 

 Gagnon, 1933) Prevot, 1938. [Bacteroides 

 siccus Eggerth and Gagnon, Jour. Bact., 25, 

 1933, 410; Prevot, Ann. Inst. Past., 60, 1938, 

 299.) 



sic'cus. L. adj. siccus dry. 



Short, thick rods about 1.0 micron long; 

 in glucose broth the cells are coccoid and 

 often grow in short chains. N on -motile. 

 Gram-negative. 



Gelatin: No liquefaction. 



Blood agar colonies: Elevated, dry, diffi- 

 cult to emulsify, 1.0 to 1.5 mm in diameter. 



Broth: Growth occurs as a powdery sedi- 

 ment with a clear supernatant fluid. 



Indole not produced. 



Hj'drogen sulfide is produced. 



Milk: Unchanged. 



Acid but no gas from fructose. No acid or 

 gas from glucose, glycerol, mannitol, sor- 

 bitol, arabinose, salicin, trehalose, amygda- 

 lin, cellobiose, glycogen, rhamnose, xylose 

 or lactose. 



Nitrites not produced from nitrates. 



Anaerobic. 



Non-pathogenic for white mice or rabbits. 



Distinctive characters: Gas is produced 

 in small amounts from peptone. Phenol red 

 and brom cresol purple are decolorized in 

 meat infusion broth. 



Source: Two strains were isolated from 

 human feces. 



Habitat : Probably the intestinal canals of 

 mammals. 



5. Sphaerophorus necroticus (Nati- 

 velle, 1936) Prevot, 1938. {Bacillus necroticus 

 Nativelle, 1936, see Weinberg et al., Les 

 Microbes Ana6robies, 1937, 693; Pr6vot, 

 Ann. Inst. Past., 60, 1938, 298.) 



ne.cro'ti.cus. Gr. noun necrus a dead 

 body; M.L. adj. necroticus necrotic. 



Short, thin, irregular rods, with a few 

 long forms, some showing bipolar staining 

 in young cultures. In 10 to 18 hours, central, 

 deep-staining, ovoid swellings appear in the 

 rods; these are not spores. After 24 hours to 

 several days, the rods disappear, and only 



amorphous elements remain. Non-motile. 

 Gram-negative. 



Gelatin: No liquefaction. 



Agar: Deep colonies small, lenticular. Gas 

 is produced. 



Glucose broth: Diffuse growth which 

 settles as a heavy, sticky deposit. Gas and 

 fetid odor. 



Milk: No acid, coagulation or peptoniza- 

 tion. 



Coagulated egg white not liquefied. 



Indole is produced. 



Acid from glucose, fructose, lactose, su- 

 crose, galactose and maltose. No acid from 

 mannitol, dextrin, inulin, amygdalin, sali- 

 cin, arabinose or glycerol. 



Anaerobic. 



Optimum temperature, 37° C. 



Pathogenicity: Slightly pathogenic in 

 pure culture. Pathogenicity more marked if 

 mixed with Escherichia coli. 



Source: One strain was isolated from a 

 case of gangrenous appendicitis. 



Habitat: Presumably found in necrotic 

 tissues of man. 



6. Sphaerophorus necrogenes (Wein- 

 berg et al., 1937) Prevot, 1938. (Bacillus, 

 Kawamura, Jour. Jap. Soc. Vet. Sci., 5, 

 1926, 22; Bacillus necrogenes Weinberg et al., 

 Les Microbes Ana^robies, 1937, 681; Prevot, 

 Ann. Inst. Past., 60, 1938, 298.) 



ne.cro'ge.nes. Gr. adj. necrus dead; Gr. 

 V. gennaio to produce; M.L. adj. necrogenes 

 necrosis-producing. 



Rods and very long filaments (50 to 100 

 microns) with swellings. Non-motile. Gram- 

 negative. 



Gas is produced. 



Serum and ascitic fluid may or may not 

 favor growth. 



Gelatin: No liquefaction. Good growth; 

 gas. 



Serum agar colonies: Small, whitish, ap- 

 pearing in 2 or 3 days; slight gas. 



Glucose agar colonies: Small, whitish; less 

 growth than on serum agar. 



Agar stab: Small, punctiform colonies; 

 gas. 



Glucose bouillon: Turbid; gas; sediment 

 and then clarification. 



Liver broth: Abundant growth; gas; gray- 



