3. Produces pink pigment. 4. Produces olive-green pigment. Cytophaga rubra. 5. Cytophaga tcnuissima. B. Weak or no growth on cellulose. Starch utilized. 1. Utilizes chitin. 6. Cytophaga johnsonii. 2. Utilization of chitin not tested. a. Produces yellow to orange pigment on starch. 7. Cytophaga deprimata. aa. Produces cream to pale-yellow pigment on starch. 8. Cytophaga alhogilva. II. From seawater. Obligately halophilic, not growing in media without at least 0.5 per cent sodium chloride. A. Produces a diffusible black to brown pigment. 9. Cytophaga krzemieniewskae. B. Do not produce a diffusible black to brown pigment. 1. Growth not inhibited by presence of 0.5 per cent peptone or 0.2 per cent glucose. 10. Cytophaga diffluens. 2. Growth inhibited by presence of 0.5 per cent peptone or 0.2 per cent glucose. 11. Cytophaga sensitiva. 1. Cytophaga hutchinsonii Winograd- sky, 1929. (Winogradsky, Ann. Inst. Past., 43, 1929, 578; Cytophaga strain 8, Jensen, Proc. Linn. Soc. N. S. Wales, 65, 1940, 547; not Cytophaga hutchinsonii Imsenecki and Solntzeva, Bull. Acad. Sci. U.S.S.R., Ser. Biol., No. 6, 1936, 1129.) hut. chin. so'ni.i. M.L. gen. noun hutchin- sonii of Hutchinson; named for H. B. Hut- chinson. Description from Stanier (Bact. Rev., 6, 1942, 191). Flexible, singly-occurring rods, 0.3 to 0.5 micron wide and 2.0 to 10.0 microns long, averaging 6.0 microns in length. Thread-like or coccoid involution forms may occur in old cultures. Gram-negative. Produces bright yellow^, glistening, mu- cilaginous patches on filter paper-silica gel or -agar plates after 3 to 5 days. The filter paper in these regions is eventually dis- solved, and the colony becomes translucent. Produces bright yellow, glistening, slimy, raised colonies on mineral glucose-agar plates. Little movement is evident, and the colonies usually remain compact. Cellulose, cellobiose and glucose are uti- lized. Xylose, arabinose, mannose, galac- tose, fructose and mannitol are not utilized. Ammonia, nitrate, aspartic acid, aspara- gine, peptone and yeast extract can serve as nitrogen sources. Catalase-positive. Aerobic. Optimum temperature, 30° C. Source: Isolated from soil. Habitat: Soil. 2. Cytophaga lutea Winogradsky, 1929. (Ann. Inst. Past., J^3, 1929, 599.) lu'te.a. L. adj. luteus yellow. Dimensions of the cells approximately those of Cytophaga aurantiaca (see below) but rather larger and thinner and without marked central swelling. Gram-negative. Produces a brilliant yellow pigment simi- lar to that of Cytophaga hutchinsonii. This species differs only in size from Cy- tophaga hutchinsonii and is probabl.y a va- riety of it. Source: Isolated from soil. Habitat: Soil. Decomposes cellulose. 3. Cytophaga aurantiaca Winograd- sky, 1929. (Winogradsky, Ann. Inst. Past., 43, 1929, 597; probably Mycococcus cyto- phagus Bokor, Arch. Microbiol., 1, 1930, 34.) au.ran.ti'a.ca. L. part. adj. aurans, au- rantis gilded; M.L. adj. aurantiacus orange- colored.
