FAMILY III. CHLOROBACTERIACEAE 



65 



sul.phur'i.ca. L. noun sulfw' (sometimes 

 sulphur) sulfur; IM.L. adj. sulphuricus sul- 

 furic. 



Cells spherical, about 0.5 to 0.7 micron 

 in diameter, usually containing sulfur glob- 

 ules. Non-motile. 



Color: Yellowish green. 



The reported occurrence of sulfur globules 

 in the cells of this very small species is sur- 

 prising; it is the only one among the sulfur 

 green bacteria in which these inclusions 



have been encountered. The published de- 

 scriptions are even more fragmentary than 

 those of other members of the group. 



Source : Reported only from sulfur springs 

 in Lubien Wielki, near Lwow, Poland. 



Habitat: Mud and stagnant water con- 

 taining rather high concentrations of hj^- 

 drogen sulfide and exposed to light; sulfur 

 springs. 



Illustration: Szafer, op. cit., 1910, PI. VI, 

 fig. 6. 



Genus IV. Chlorohaclerium Lauterborn, 1915. 



(Luuterborn, Verhandl, naturhist.-medizin. Vereins, Heidelberg, N.F., 13, 1915, 429; not 

 Chlorobacteriwn* Guillebeau, Landw. Jahrb. d. Schweiz, 4, 1890, 32.) 



Chlo.ro. bac.te'ri.um. Gr. adj. chlonis green; L. noun bacterium a small rod; M.L. neut.n. 

 Chlorobacterium a green rodlet. 



Sulfur green bacteria(?) which grow sj'mbiotically as an outside covering on cells of pro- 

 tozoa, such as amoeba and flagellates. Cells rod-shaped, often slightly curved, greenish. 

 Non-motile. 



The type species is Chlorobacterium symhioticum Lauterborn. 



1. Chlorobacterium symbioticum Lau- 

 terborn, 1915. (Verhandl. naturhist.-medi- 

 zin. Vereins, Heidelberg, X.F., IS, 1915, 

 429.) 



sym.bi.o'ti.cum. Gr. adj. stjnibioticus of 

 companionship, sj'mbiotic. 



Cells rod-shaped, about 0.5 by 2 to 5 

 microns, often slightly curved. Non-motile. 



Occur as a peripheral covering of certain 

 protozoa with which they may form a sym- 

 biotic unit. 



It is not certain that this is a sulfur green 



bacterium: the descriptions of localities 

 Avhere it was found fail to mention the pres- 

 ence of hydrogen sulfide in the environ- 

 ment; this should be a prerequisite for a 

 member of this group. 



Source : Reported from a number of pools 

 in Germany. 



Habitat: Stagnant water. 



Illustrations: Lauterborn, loc. cit., PL III, 

 fig. 34-36; Pascher, Die Siisswasserflora 

 Deutschlands, Osterreichs und der Schweiz, 

 Jena, 12, 1925, fig. 149. 



Genus V . Chlorochromatiuni Lauterborn, 1906. 

 (Allgem. botan. Ztschr., 19, 1906, 196.) 



Chlo.ro. chro.ma'ti.um. Gr. adj. chlorus green; Gr. noun chromatium color, paint; M.L. 

 neut.n. Chromatium a bacterial genus; M.L. neut.n. Chlorochromatium a green Chromatium. 



Sulfur green bacteria, ovoid to rod -shaped with rounded ends. Occur as barrel -shaped 

 aggregates consisting of a rather large, colorless, polar flagellate bacterium as the center 

 which is surrounded by green bacteria, arranged in 4 to 6 rows, ordinaril}' from 2 to 4 cells 

 high. The entire conglomerate behaves like a unit, is motile, and multiplies by the more or 

 less simultaneous fission of its components. 



The green constituents contain a chlorophyllous pigment which is not identical with the 

 common green plant chlorophylls or with bacteriochlorophjdl. Capable of photosj-nthesis 

 in the presence of hydrogen sulfide but do not store sulfur globules in the cells. 



The type species is Chlorochromatium aggregatum Lauterborn. 



* It has been proposed that Chlorobacterium Guillebeau be rejected as a generic name in 

 bacteriology and placed in the list of nomina generica rejicienda (Internat. Bull. Bact. 

 Nomen. and Tax., 1, 1951, 43 and 2, 1952, 110). 



