Pleomorphic rods, 0.4 to 0.7 by 0.7 to 2.8 microns, occasional!}^ club-shaped, occur- ring singly and in an angular arrangement due to the snapping division of the cells. Non-motile. Gram-positive. Gelatin: No liquefaction. Nutrient-glucose agar colonies: White to cream, circular, smooth, entire, convex, translucent, 1 to 2 mm in diameter. Broth: Turbid in 36 to 48 hours; no pelli- cle; light sediment. Litmus milk: Slow reduction of litmus, but no other change. Acid but no gas from glucose, mannitol and glycerol. No growth in lactose or raffi- nose. Starch not hydro^^zed. No growth in Koser citrate medium. Nitrites not produced from nitrates. Growth in 3 per cent salt. Catalase-positive. Aerobic to slightly microaerophilic. Temperature relations: Optimum, be- tween 24° and 28° C. Minimum, 6° C. Max- imum, between 34° and 36° C. Source: Isolated from wet wood of Lom- bardy poplar {Populus nigra var. italica). Habitat: Pathogenic on Populus nigra var. italica and on P. tremuloides. 21. Corynebacterivim inichiganense (Erw. Smith, 1910) Jensen, 1934. {Bacterium michiganense (Erw. Smith, Science, 81, 1910, 794; Jensen, Proc. Linnean Soc. New So. Wales, 59, 1934, 47.) mi.chi.ga.nen'se. M.L. ad'], michiganensis pertaining to Michigan. Description taken from Bryan (Jour. Agr. Res., 41, 1930, 825). Rods 0.6 to 0.7 by 0.7 to 1.2 microns. Char- acteristic angular growth with branching and club-shaped cells (Jensen, op. cit., 1934, 47). Encapsulated. Non-motile. Gram-posi- tive. Beef agar colonies: Growth slow, mustard- yellow, smooth, glistening, butyrous. Chromogenesis: Develops yellowish brown, light ochre-yellow to sepia-brown colors on suitable media (Jensen, loc. cit.). Gelatin: Slow liquefaction. Broth: Turbidity slow and moderate. Milk: Slow coagulation. No peptoniza- tion. Indole not produced. Hydrogen sulfide not produced. Acid from glucose, sucrose, galactose, fructose, maltose, and slight acid from lac- tose, glycerol and mannitol. Starch: Very weak diastatic action. Nitrites not produced from nitrates. Utilizes peptone but not ammonia, nitrite, nitrate, tyrosine, asparagine or glutamic acid (Mushin, Austral. Jour. Exp. Biol, and Med., 16, 1938, 326). No growth in 3 per cent salt. Aerobic. Temperature relations: Optimum, be- tween 25° and 27° C. Minimum, 1° C. Max- imum, 33° C. Comments: A non -pathogenic variety of this species has been reported by Jensen (op. cit., 1934, 48); it grows more rapidly with more moist growth, has a higher max- imum temperature and has a stronger pro- teolytic activity than does the pathogenic strain. Source; Isolated from the bacterial canker of tomato. Habitat: Pathogenic on tomato. 22. Corynebacteriuni rathayi (Erw. Smith, 1913) Dowson, 1942. {Aplanobacter rathayi Erw. Smith, Science, 38, 1913, 926; also see Bact. in Rel. to Plant Dis., 3, 1914, 155; Dowson, Trans. Brit. Myc. Soc, 25, 1942, 313.) ra.thay'i. M.L. gen. noun rathayi of Ra- thay; named for E. Rathay, an Austrian plant pathologist who was the first to isolate this species. Rods 0.6 to 0.75 by 0.75 to 1.5 microns. Encapsulated. Non-motile. Not acid-fast. Gram-positive. Gelatin: Slow liquefaction after 7 weeks. Agar colonies: Small, j^ellow, slow-grow- ing. Milk: Growth slow. Yellow ring. Litmus milk: Alkaline and reduced. Potato plugs: Good, yellow, viscid growth. Acid but no gas from glucose, sucrose and lactose. Nitrites produced from nitrates. Cohn's solution: No growth. Heavy inoculum necessary in media.
