This is the commonest Bacteroides species found in the feces of adults. Differs from Bacteroides incommunis in that it does not ferment am3'gdalin and cellobiose but does ferment glj^cogen and starch. Liquefies gelatin. Source: Thirty-eight strains were iso- lated from human feces. Habitat: Probablj' the intestinal canals of mammals. 21. Bacteroides distasonis Eggerth and Gagnon, 1933. (Eggerth and Gagnon, Jour. Bact., 25, 1933, 403; Ristella distasonis Prevot, Ann. Inst. Past., 60, 1938, 291.) dis.ta.so'nis. M.L. gen.noun distasonis of Distaso; named for A. Distaso, a Rouma- nian bacteriologist. Rods, 0.5 to 0.8 b}^ 1.5 to 2.5 microns, with rounded ends, occurring singly; some strains show a few bacilli 5.0 to 8.0 microns long. Non-motile. Stain solidly. Gram-negative. Gelatin: No liquefaction by 16 strains; liquefaction by the remaining four strains in 35 to 50 days. Blood agar colonies: Soft, gra3-ish, ele- vated, 1.0 to 1.5 mm in diameter. Two strains are markedly hemolytic. Broth: Growth is diffuse. Milk: Acidified. All but 4 strains coagu- late milk. Indole not produced. Hydrogen sulfide is produced. Acid but no gas from amygdalin, cello- biose, dextrin, fructose, galactose, glucose, inulin, lactose, maltose, mannose, melezi- tose, raffinose, rhamnose, salicin, sucrose, trehalose and xylose. Fifteen strains fer- ment esculin. Fifteen strains slowly ferment starch. No acid or gas from arabinose, glj'co- gen, glycerol, mannitol or sorbitol. Nitrites not produced from nitrates. Peptone: No gas. Anaerobic. Non-pathogenic for white mice or rabbits. Distinctive characters: Usually fails to liquefy gelatin. Fails to ferment arabinose. Source : Twenty strains were isolated from human feces. Habitat: Probably the intestinal canals of mammals. 22. Bacteroides capillosus (Tissier, 1908) Kelly, comb. nov. (Bacillus capillosus Tissier, Ann. Inst. Past., 22, 1908, 189; Ristella capillosa Prevot, Ann. Inst. Past., 60, 1938, 292.) ca.pil.lo'sus. L. adj. capi7Zosws very hairy. Long, thick rods, 1 by 4 to 5 microns, occurring singly or in chains; curved and filamentous forms are present, and they may become tangled. Non-motile. Gram-nega- tive. Gelatin: No liquefaction. Agar: Deep colonies fine, granular, ir- regular, fimbriate. No gas produced. Broth: Slight turbidity. Milk: Growth but no change. Coagulated egg white not digested. Indole not produced. Hydrogen sulfide not produced. Slight acid from glucose. No acid from lactose or sucrose. Anaerobic. Optimum temperature, 37° C. Not pathogenic. Source: Isolated twice from the intestines of infants. Habitat: Found in the intestinal tract of man. 23. Bacteroides cylindroides (Rocchi, 1908) Kelly, comb. nov. (Bacterium cylin- droides Rocchi, Lo stato actuale delle nostre cognizioni sui germi anaerobi Gamberine e Parmezziani, Bologna, 1908; Ristella cylin- droides Prevot, Ann. Inst. Past., 60, 1938, 292.) cy.lin.dro.i'des. Gr. noun cylindrus a cjdinder; Gr. noun idus form, shape; M.L. adj. cylindroides cylinder-shaped. Large, filamentous rods, 6 to 8 microns long, with granular, swollen areas. Non- motile. Gram-negative. Gelatin: No liquefaction. Glucose agar: Deep colonies small, round. Glucose broth: Turbid with light deposit. Milk: Unchanged. Albumin not digested. Acid from glucose and sucrose. No acid from lactose, galactose, mannitol or dulci- tol. Anaerobic. Grows only at 18° C. Not pathogenic.
