crons; possess fusiform or spherical swell- ings. Non-motile. Gram-positive. Gas produced in culture media. Gelatin: Liquefaction. Deep agar colonies : Large (3 to 5 mm in diameter), flocculent, arborescent. Medium broken bj' gas. Rancid odor. Acidified. Glucose broth: Turbid. Flaky sediment. Abundant gas. Rancid odor. Acidified. iNIilk: Acidified; not coagulated. Gas is produced. Rancid odor. Coagulated proteins not attacked. Hj'drogen sulfide is produced. Acid from glucose, maltose, sucrose, sorbi- tol, mannitol and glycerol. Ammonia, alcohols, acetylmethylcarbinol and formic, butj^ric and lactic acids are produced. Nitrites not produced from nitrates. Neutral red and phenosafranin not re- duced. Anaerobic. Optimum temperature, 37° C. Killed at 60° C. Not pathogenic or only slightlj- so; causes minor abscesses in rabbits. Source: Isolated from the mouth of a breast-fed infant; also from pond mud. Habitat: Unknown. 2. Catenabacteriuni filaineiitosuin Prevot, 1938. (Jungano, Compt. rend. Soc. Biol., Paris, 66, 1909, 112 and 122; Prevot, Ann. Inst. Past., 60, 1938, 295.) fi.la.men.to'sum. L. nounfilum a thread; ALL. noun filamentum a filament; M.L. adj. fikimentosus full of filaments. Large rods with rounded ends. Pleo- morphic, occurring either as short and swol- len or long and curved forms. Bifurcation. Non-motile. Gram-positive. Slight amount of gas produced (on agita- tion) in culture media. Gelatin: No liquefaction. Deep agar colonies: Rather large, white, lenticular. Slight gas. Glucose broth: Turbid. Slight gas. Peptone broth: Slight turbidity. Milk: Coagulated. Coagulated proteins not attacked. Indole not produced. Acid from glucose, fructose, maltose, ga- lactose, lactose and sucrose. Ammonia, volatile amines, alcohol, ace- tylmethylcarbinol, acetic and lactic acids and traces of formic and propionic acids are produced. Nitrites not produced from nitrates. Neutral red reduced. Anaerobic. Optimum temperature, 37° C. Not pathogenic for guinea pigs or mice. Source: Isolated from the intestine of a rat; also from cases of acute appendicitis, lung abscess, putrid pleurisy and uterine suppuration. Habitat: Found in the intestine of the rat and in the natural cavities of man. Com- 3. Catenabacteriuni contortuin Pre- vot, 1947. (Ann. Inst. Past., 73, 1947, 414.) con.tor'tum. L. adj. confortus twisted. Rods, 0.5 to 0.7 by 3.0 to 4.0 microns, oc- curring in long, twisted chains of 30 to 50 or more elements. Non-motile. Gram-posi- tive. Gas but no odor produced in culture me- dia. Gelatin: No liquefaction. Deep agar colonies: Lenticular. Gas is produced. Peptone broth: Little or no growth. Glucose broth: Slowly turbid; growth occurs as a viscid, semifluid mass. Gas is produced. Milk: No coagulation. Coagulated proteins not attacked. Indole is produced. Acid and gas from glucose, fructose, malt- ose, galactose, sucrose, xylose and arabi- nose. Ammonia, formic, propionic and lactic acids, volatile amines, aldehydes, alcohols and acetylmethjdcarbinol are produced. Nitrites not produced from nitrates. Neutral red reduced. Anaerobic. Optimum temperature, 37° C. Neither toxin nor hemolysin is produced. One strain pathogenic for guinea pigs, causing death in 48 hours. Source: Isolated from two cases of putrid, gangrenous appendicitis. Habitat: Found in human intestines. Un-
