Johnson and Shiink (Jour. Bact., 31, 1936, 589). Short, thick rods, 0.4 to 0.8 by 1.0 to 2.5 microns, with rounded ends, occurring singly and in pairs. Occasional rods slightly curved, ends slightly pointed. Not encap- sulated. Motile. Johnson, Zworykin and Warren (Jour. Bact., 46, 1943, 167) made pictures with the electron microscope of a culture which they identified with this species; the organism showed a tuft of polar flagella. Gram-negative. Sea-water gelatin colonies : After 48 hours, colonies small (less than 0.5 mm in diam- eter), circular, entire, homogeneous, with slight liquefaction. Sea-water gelatin stab: Slight, infundi- buliform liquefaction, sometimes slightly beaded, tending to become crateriform in old cultures. Nutrient sea-water agar colonies: Small, circular, smooth, entire, slightly raised, homogeneous, iridescent. Old colonies be- come yellowish with margins slightly ser- rate. Sea-water agar slant: Growth abundant, grayish to jellowish, smooth, viscous, homogeneous, iridescent. Growth on autoclaved fish: Moderate, grayish to yellowish, smooth, glistening, luminescent, no odor of putrefaction. Sea water containing 0.2 per cent peptone : Moderate growth, mostly near the surface; very thin pellicle; sediment found in old tubes. Milk: No growth. Milk with 2.8 per cent sodium chloride : Slight growth and lumines- cence, but no action on the milk. Potato plugs resting on cotton saturated in sea water: Growth fairly abundant, spreading, slightly brownish, luminous. Blood serum: No growth. Indole not produced. Hydrogen sulfide is produced. Acid but no gas from glucose (Gorham, in Dahlgren, Jour. Franklin Inst., 180, 1915, 517 and insert following 714). Acid from glycerol, fructose, galactose, mannose, maltose, cellobiose, dextrin and salicin. No acid or gas from lactose, sucrose, arabi- nose, xylose, fucose, rhamnose, trehalose, raffinose, glycogen, inulin, adonitol, dulci- tol, inositol, sorbitol, erythritol, arabitol or alpha-methyl-glycoside. Starch hydrolysis is doubtful or verj' slight. Decarboxjlates glutamic acid to form 7-aminobutyric acid and CO2 ; decarboxjd- ates lysine (Pearson, Jour. Cell, and Comp. Physiol., 41, 1953, 65). Alanine, arginine, aspartic acid, glutamic acid and threonine are capable of serving as sole nitrogen sources for this organism (Pearson, Jour. Tenn. Acad. Sci., 27, 1952, 229). Nitrites produced from nitrates. Ammonia produced in peptone media. Aerobic, facultatively anaerobic. Temperature relations: Optimum, be- tween 25° and 28° C. Minimum, between 5° and 10° C. No growth at 37° C. Optimum temperature for luminescence, 28° C. Weak at 10° C., none at 5° nor at 37° C. Optimum pH for luminescence, between 7.4 and 7.8; less intense at 7.0 and 8.2. Fischer (Erg. d. Plankton Expedition d. Humboldt-Stiftung, 4, 1894) noted that this organism grows best in alkaline rnedia. Quality of luminescence: Orangish, main- tained for 5 to 8 weeks (Beijerinck); green- ish (Johnson and Shunk). Luminescence favored by the presence of glycerol in the medium. Salt tolerance: The osmotic tension of inorganic salt solutions used as media for this species must be equivalent to that produced in a 2.8 to 3.0 per cent sodium chloride solution to assure luminescence and good growth. Not pathogenic for white rats. Distinctive character: Luminescence on organic matter occurs only when there is a suflftcient proportion of inorganic salt pres- ent. Source: Isolated from sea water at Kiel and from herring. Habitat: Frequentlj^ found on dead fish, Crustacea and other salt-water animals and in coastal sea water. Phosphorescent bac- teria also occur on meat and even on sol- dier's wounds where they produce no known harmful effects. No food poisoning has been traced to meat on which these organisms have grown (Niven, Circular No. 2, Ameri- can Meat Inst. Foundation, 1951, 1-11).
