aa. Colonies j^ellow. No liquefaction of gelatin. Causes a wilt and canker of to- matoes. 21. Corynebacterium michiganense . 2. Nitrites produced from nitrates. Slow or no liquefaction of gelatin. a. Colonies yellow. b. Slow liquefaction of gelatin. Attacks members of the grass family. 22. Corynebacterium rathayi. bb. No liquefaction of gelatin. Attacks members of the grass family. 23. Corynebacterium agropyri. aa. Colonies orange. Parasitic on sweet peas, etc. 24. Corynebacterium fascians. B. Motile, usually by means of a single flagellum. 1. Non-chromogenic on beef extract agar media. a. Colonies white on beef extract agar media. 25. Corynebacterium hypertrophicans . aa. Colonies colorless and almost transparent on beef extract agar media. Sal- mon- to flesh-colored on potato glucose agar. 26. Corynebacteriiim poinsettiae. 2. Yellow colonies on beef extract agar. a. Nitrites produced from nitrates. 27. Corynebacterium tritici. aa. Nitrites not produced from nitrates. 28. Corynebacterium flaccumfaciens . 2. ANAEROBIC TO AEROTOLERANT. I. Acid but no gas produced in glucose-agar shake media. A. Gelatin liquefied. 29. Corynebacterium acnes. B. Gelatin not liquefied. 1. Carbohydrates generally not attacked; slight acid from glucose. Pathogenic. 30. Corynebacterium parvum. 2. Carbohydrates attacked. Not pathogenic. 31. Corynebacterium granulosum. II. Acid and gas produced in glucose-agar shake media. A. Gelatin liquefied. 32. Corynebacterium avidum. B. Gelatin not liquefied. 33. Corynebacterium diphiheroides. 1. Corynebacterium diphtheriae Common name: Diphtheria bacillus; (Fliigge, 1886) Lehmann and Neumann, Klebs-Loeffler bacillus. 1896. (Die Klebs'schen Stabchen, Loffler, Rods, varying greatly in dimensions, 0.3 Mitteil. a. d. kaiserl. Gesundheitsamte, 2, to 0.8 by 1.0 to 8.0 microns, occurring singly. 1884, 421; Bacillus diphtheriae Flugge, Die The rods are straight or .slightly curved, Mikroorganismen, 2 Aufl., 1886, 225; Leh- frequently swollen at one or both ends. The mann and Neumann, Bakt. Diag., 1 Aufl., rods do not, as a rule, stain uniformly with 2, 1896, 350; Corynebacterium ulcerans Gil- methylene blue but show alternate bands bert and Stewart, Jour, of Lab. and Clin. of stained and unstained material and in Med., 12, 1927, 756.) addition one or more metachromatic gran- diph.the'ri.ae. Gr. noun diphthera leather, ules which are best shown by special stains, skin; M.L. fem.n. diphtheria diphtheria; Non-motile. Gram-positive but not in- M.L. gen. noun diphtheriae of diphtheria. tensely so in older cultures.
