2. Require serum or ascitic fluid for growth. a. Gelatin not liquefied, b. Acid from glucose. 15. Sphaerophorus abscedens. bb. No acid from glucose. 16. Sphaerophorus caviae. aa. Gelatin liquefied slowly. 17. Sphaerophorus glycohjticus. II. Motile. ^xh-genxs Sphaerocillus Pr6vot {loc. cit.). 18. Sphaerophorus bullosus. 1. Sphaerophorus necrophorus (Fliigge, 1886) Pr^vot, 1938. (Bacillus der Kalber- diphtherie, Loeffler, Mitteil. kaiserl. Gesund- heitsamte, B, 1884, 493; Bacillus diphtheriae vitulorum Fliigge, Die Mikroorganismen, 2 Aufl., 1886, 265; Bacillus necrophorus Fliigge, ibid., 273; Streptothrix cuniculi Schmorl, Deutsch. Ztschr. f. Tiermed., 17, 1891, 376; Bacillus funduliformis Hall6, Inaug. Diss., Paris, 1898; Bacillus theto- ides Rist, These de Paris, 1898; Actinomyces necrophorus Lehmann and Neumann, Bakt. Diag., 2 Aufl., 2, 1899, 434; Cohnistreptothrix cuniculi Chalmers and Christopherson, Ann. Trop. Med., 10, 1916, 273; Bactero- ides funduliformis Bergey et al.. Manual, 3rd ed., 1930, 373; Pr6vot, Ann. Inst. Past., 60, 1938, 298; Spherophorus funduliformis Pre- vot, loc. cit.; Bacterium funduliforme Dack, Jour. Inf. Dis., 62, 1938, 169; Necrobacter- ium necrophorus (sic) Jonsen and Thj0tta, Acta Path, et Microbiol. Scand., 25, 1948, 698.) ne.cro'pho.rus. Gr. adj. necrus dead; Gr. adj. phorus bearing; M.L. adj. necrophorus necrosis-producing. Rods, 0.5 to 1.5 by 1.5 to 3.0 microns in pathological processes. Extremely pleo- morphic, especially in cultures, showing filamentous forms up to 80 to 100 microns in length and even branching forms, as re- ported by some authors. Schmorl (Deutsch. Ztschr. f. Tiermed., 17, 1891, 376) states that the short forms are motile, whereas Lahelle {Necrobacterium, Oslo, 1947, 166) and other recent investigators report this species to be non-motile and non-flagellated. Gram- negative. Foul odor produced in all media. Gelatin: No liquefaction. Agar colonies: Small, circular, opaque. dirty white; yellowish center under low power lens; floccose margin. Agar stab : Yellowish colonies along needle track; gas bubbles are produced. Blood agar: Hemolysis of human and rabbit erythrocytes; weak hemolysis of ox erythrocytes; no hemolysis of horse, sheep or goat erythrocytes. Broth: Turbid, flocculent growth; gas and a cheese-like odor are produced. Litmus milk: Coagulation then digestion of the coagulum; neutral reaction after 1 week. Coagulated egg white: No digestion. Indole is produced. Hydrogen sulfide is produced. Acid and gas from glucose, fructose and maltose. No acid or gas from lactose, su- crose, mannitol or glycerol. Nitrites not produced from nitrates. Ammonia not produced. Anaerobic. Temperature relations: Optimum, be- tween 30° and 40° C. No growth at 21° or at 45° C. Sparse growth at 22° and at 44° C. Optimum pH, between 7.5 and 7.8. Hemotoxin is produced. Pathogenicity: Some strains are patho- genic for rabbits, guinea pigs and mice but not for white rats. Comments: Dack, Dragstedt, Johnson and McCullough (Jour. Inf. Dis., 62, 1938, 169) made a comparative study of Sphaero- phorus funduliformis and Sphaerophorus necrophorus with respect to their growth re- quirements, their colonial morphologies, their cell morphologies on different media, their biochemical reactions, their patho- genicities for rabbits and their abilities to ulcerate the colons of experimental animals. Their study indicated that no distinction exists between these two organisms. Al-
