Temperature relations: Optimum, 37° C. Some strains grow at 22° C. Optimum pH, between 6.0 and 8.0. Growth occurs in broth at pH 5.5. Slowly plasmolyzed in 5 per cent NaCl solution. Non-pathogenic (Lewkowicz's strains). Two strains (Prevot's) were pathogenic for rabbits. Distinctive characters : Differs from Veil- lonella parvula in that it does not ferment sugars, does not produce hydrogen sulfide nor indole, is not hemolytic, does not pro- duce nitrites from nitrates and does not develop fetid odors. Source: Isolated from the mouth of a healthy infant (Lewkowicz). Twenty-four strains were isolated from human saliva (Hall and Howitt). Of the fifteen strains isolated by Prevot, one was from alveolar pyorrhoea, one from a case of pulmonary gangrene, five from tonsils, one from an ap- pendix, two from cases of measles, three from cases of scarlet fever and two from normal guinea pigs and rabbits. Habitat: Prevalent in the salivas of man and other animals. 2a. Veillonella alcalescens var. gingivalis Prevot, 1933. (Kleiner Micrococcus, Ozaki, Cent. f. Bakt., I Abt., Orig., 62, 1912, 83; Micrococcus gingivalis Bergey et al., Man- ual, 1st ed., 1923, 69; Prevot, Ann. Sci. Nat., Ser. Bot., 15, 1933, 133.) gin.gi.va'lis. L. noun gingiva a gum; M.L. adj . gingivalis pertaining to a gum. Differs from Veillonella alcalescens by its ability to grow at 22° C. and by the fact that glucose, although favoring growth, is not fermented. Source: Isolated from the oral cavity. Two strains were isolated from the intes- tines (Prevot). 2b. Veillo7iella alcalescens var. mimitis- sima Prevot, 1933. {Micrococcus minutis- siinus Oliver and Wherry, Jour. Inf. Dis., 28, 1931, 342; Pr6vot, Ann. Sci. Nat., S^r. Bot., 15, 1933, 134.) mi.nu.tis'si.ma. L. sup. adj. minutissi- mus smallest. Differs from Veillonella alcalescens only in that the usual carbohydrates favor growth and that the gas produced is not absorbed by sodium hydroxide and is not inflammable. Non-pathogenic for rabbits, guinea pigs or white mice (Oliver and Wherry). Source: Two strains were isolated from a mixed infection in aphthous ulcers of the gingival and buccal mucosa of a case of post-poliomyelitic paralysis. 2c. Veillonella alcalescens var. syzygios Prevot, 1933. (Syzygiococcus scarlatinae Herzberg, Cent. f. Bakt., I Abt., Ref., 90, 1928, 575; Micrococcus syzygios scarlatinae Herzberg, Cent. f. Bakt., I Abt., Orig., Ill, 1929, 373; Micrococcxis syzygios Bergey et al., Manual, 3rd ed., 1930, 92; Prevot, Ann. Sci. Nat., Ser. Bot., 15, 1933, 134.) sy.zy'gi.os. Gr. adj. syzygios yoked to- gether. Differs from Veillonella alcalescens only by its ability to grow under an atmospheric pressure of 4 cm of mercury with the pro- duction of hydrogen sulfide in small amounts by some strains and the production of nitrites from nitrates. Source: Isolated by Herzberg in 30 per cent of normal mouths and in 100 per cent of salivas from scarlet fever patients. 3. Veillonella discoides (Prevot, 1933) Pelczar, comb. nov. (Neisseria discoides Pre- vot, Ann. Sci. Nat., Ser. Bot., 15, 1933, 106.) dis.co.i'des. Gr. adj. discoides disc- shaped. Spheres, 0.6 to 0.7 micron in diameter, occurring in pairs or tetrads. Gram-nega- tive. Gelatin: No liquefaction. Agar deep colonies: Lenticular, up to 1 mm in diameter. Grows in a narrow disc about 1 cm below the surface. Gas pro- duced. Broth: Turbid; fine, granular precipitate. Slight rancid odor and inflammable, ex- plosive gas produced. Peptone water: Gas produced. Milk: No action. Indole not produced. Hydrogen sulfide not produced. Coagulated proteins: No digestion. Carbohydrates not attacked.
