FAMILY XIII. BACILLACEAE 



645 



fermented. Sucrose, salicin, dulcitol and 

 inositol not attacked. 



Nitrites not produced from nitrates. 



Coagulated albumin: No liquefaction. 



Blood agar: No hemolysis. 



Blood serum: No liquefaction. 



Brain medium (Hibler) : No blackening or 

 digestion even in the presence of an iron 

 strip. 



Anaerobic. 



Optimum temperature not determined. 

 Grows well both at 37° C. and at room tem- 

 perature. 



Not pathogenic for white mice, guinea 

 pigs or rabbits. 



Distinctive character: Submerged colo- 

 nies extremely gummatous. 



Source: Isolated once from gaseous gan- 

 grene and twice from normal human feces 

 (adult and infant). 



Habitat: Decomposing organic matter, 

 so far as known. 



Indole not produced (Duffett, Jour. Bact., 

 29, 1935, 576). 



Acid and gas from glucose, galactose, 

 fructose, maltose, lactose, sucrose, inulin, 

 salicin and starch. Glycerol and mannitol 

 not fermented. Records wM-y in regard to 

 action on lactose, inulin and salicin. 



Coagulated albumin: No liquefaction. 



Blood serum: No liquefaction. 



Brain medium: No blackening or diges- 

 tion. 



Meat medium: Reddened; no blackening 

 or digestion. 



Anaerobic. 



Optimum temperature, not recorded. 

 Grows well at 37° C. 



A weak exotoxin is produced. 



Pathogenicity for guinea pig variable 

 and commonly lost in cultivation. 



Source: Isolated from war wounds, appen- 

 dicitis and once from black-leg of sheep. 



Habitat: Presumably widely distributed. 



7. Clostridium fallax (Weinberg and 

 Seguin, 1915) Bergey et al., 1923. (Bacille A, 

 Weinberg and Seguin, Compt. rend. Soc. 

 Biol., Paris, 78, 1915, 277; Bacillus fallax 

 Weinberg and Seguin, ibid., 686; Bergey et 

 al., Manual, 1st ed., 1923, 325; Clostridium 

 pseudo-fallax Prevot and Loth, Ann. Inst. 

 Past., 67, 1941, 244.) 



fal'lax. L. adj. fallax deceptive, false. 



Rods, 0.6 by 1.2 to 5.0 microns, occurring 

 singly or rarely in pairs. Spores, rarely ob- 

 served, are ovoid, eccentric to subterminal 

 and swell the cells. Encapsulated in body 

 fluids. Motile by means of peritrichous fla- 

 gella. Gram-positive. 



Gelatin: No liquefaction. 



Glucose agar surface colonies (anaerobic) : 

 Circular, flat; transparent, crenated margin. 



Glucose agar deep colonies: Lenticular, 

 bean-shaped, irregular, smooth. 



Agar slant (anaerobic) : Grayish film. 



Broth: Poor growth; slight, diffuse tur- 

 bidity. 



Glucose broth: Abundant turbidity and 

 gas. Clearing by sedimentation. 



Litmus milk: Acid; slowly coagulated. 

 Litmus reduced. Clot channeled by gas but 

 not digested. 



8. Clostridium difficile (Hall and 

 O'Toole, 1935) Prevot, 1938. {Bacillus diffi- 

 cilis Hall and O'Toole, Amer. Jour. Dis. 

 Child., 49, 1935, 390; Clostridium difficilis 

 (sic) Prevot, Ann. Inst. Past., 61, 1938, 84.) 



dif.fi'ci.le. L. adj. difficilis difficult. 



Heavily bodied rods. Spores elongated 

 and subterminal, slightly swelling the cells. 

 Actively motile. Gram-positive. 



Gelatin: No liquefaction. 



Agar deep colonies: Minute, flat, opaque 

 discs, becoming lobate. 



Egg yolk agar surface colonies: Irregular, 

 flattened, dry, roughened, somewhat gran- 

 ular, with little or no color. No precipitate 

 in the agar nor luster on the colony. 



Milk: Poor growth. Gas produced in 

 traces, but milk unchanged. 



Acid and gas from glucose, fructose, man- 

 nitol, salicin and xylose. Traces of gas but 

 no acid from galactose, maltose, sucrose, 

 lactose, raffinose, inulin and glycerol. 



Nitrites produced from nitrates (Reed, 

 Jour. Bact., 44, 1942, 425). 



Coagulated albumin: No liquefaction. 



Blood agar surface colonies (anaerobic) : 

 Irregular, flat; no hemolysis. 



Blood serum: No liquefaction. 



