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MANUAL OF DETERMINATIVE BACTERIOLOGY 



hydrogen sulfide, and exposed to light; 

 sulfur springs. 



Illustrations: Perfiliev, loc. cit., PI. II, 

 fig. 2; Lauterborn, loc. cit., PI. Ill, fig. 

 29-31. 



3. Pelodictyon parallelum Perfiliev. 

 (Aphanothece parallela Szafer, Bull. 

 Acad. Sci., Cracovie, S^r. B, 3, 1910, 163; 

 Perfiliev, Jour. Microbiol. (Russian), 1, 

 1914, 198; Pediochloris parallela Geitler, 

 Die Siisswasserflora Deutschlands, Os- 

 terreichs und der Schweiz, Jena, 12, 1925, 

 457.) From Latin parallelus, beside 

 one another. 



Cells: Rather small, spherical to ovoid, 

 or even rod-shaped; about 0.5 to 1 micron 



by 1 to 3 microns, occurring in chains, 

 and forming flat, plate-like, two-dimen- 

 sional aggregates in which the chains are 

 arranged as parallel strands. 



Color yellowish-green. Xon-motile. 



Abnormal cell forms not specifically 

 mentioned, but likely to occur, and to 

 resemble those of other species. 



This species may well be a special 

 growth-form of Chlorobium limicola. 



Habitat: Mud and stagnant water con- 

 taining rather high concentrations of 

 hydrogen sulfide and exposed to light; 

 sulfur springs. 



Illustrations: Szafer, loc. cit., PI. VI, 

 fig. 7; Perfiliev, loc. cit., PI. II, fig. 2. 



Genus III. Clathrochloris Geitler. 



(Die Susswasserflora Deutschlands, Osterreichs und der Schweiz, Jena, 12, 1925, 

 457.) From Greek clathros, trellis and chloros, green. 



Green sulfur bacteria of small size, generally spherical, and arranged in chains 

 which are united into loose, trellis-shaped aggregates, somewhat similar to those of 

 Pelodictyon clathratifornie and Pelodictyon aggregatum. Cells usually contain sulfur 

 globules. Color yellowish-green. Non-motile. 



The type species is Clathrochloris snlphurica (Szafer) Geitler. 



1. Clathrochloris sulphurica (Szafer) 

 Geitler. {Aphanothece sulphurica Sza- 

 fer, Bull. Acad. Sci., Cracovie, S6r.B, 3, 

 1910, 162; Geitler, Die Siisswasserflora 

 Deutschlands, Osterreichs und der 

 Schweiz, Jena, 12, 1925, 457.) From 

 Latin, containing sulfur. 



Cells: Spherical, about 0.5 to 0.7 mi- 

 cron in diameter, usually containing 

 sulfur globules. Color yellowish-green. 

 Xon-motile. 



The reported occurrence of sulfur 

 globules in the cells of this very small 

 species is surprising; it is the only one 



among the green sulfur bacteria in which 

 these inclusions have been encountered. 

 The published descriptions are even more 

 fragmentary than those of other mem- 

 bers 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 

 hydrogen sulfide and exposed to light; 

 sulfur springs. 



Illustration: Szafer, loc. cit., PI. VI, 

 fig. 6. 



Genus IV. Chlorobacterixun Lauterborn. 



(Lauterborn, Verhandl. naturhist.-medizin. Vereins, Heidelberg, N.F., 13, 1915, 

 429; not Chlorobacterium Guillebeau, Landw. Landw. Jahrb. d. Schweiz, 4, 1890, 32; 

 Chroostipes Pascher, Die Siisswasserflora Deutschlands, Osterreichs und der Schweiz, 

 Jena, 12, 1925, 116.) From Greek chloros, green and Latin bacterium, a small rod. 



Green sulfur bacteria(?) which grow symbiotically as an outside covering on cells 

 of protozoa, such as amoeba and flagellates. Cells rod -shaped, often slightly curved, 

 greenish. Non-motile. 



The type species is Chlorobacterium symbiolicum Lauterborn. 



