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MANUAL OF DETERMINATIVE BACTERIOLOGY 



like structure. This behavior has been ascribed to a change in the mode of cell divi- 

 sion which at first appears to take place in three perpendicular planes, and later 

 presumably changes to a division in only two directions. Cells when free are motile 

 by means of polar fiagella. In pure culture also this type rarely, if ever, produces 

 large aggregates with the development here mentioned as characteristic for the 

 genus (Bavendamm, Die farblosen und roten Schwefelbakterien, Pflanzenforschung, 

 Heft 2, 1924, 76). This, along with the other similarities, makes it doubtful whether 

 future studies will result in the retention of the genera Lnmprocystis and Thiocystis 

 side by side. Produce bacteriochlorophyll and carotenoid pigments, coloring the 

 cell masses purplish-pink to red. Capable of photosynthesis in the presence of hy- 

 drogen sulfide, storing elementary sulfur as globules inside the cells. 



The type species is Lamprocystis roseopersicina (Kiitzing) Schroeter. 



1. Lamprocystis roseopersicina (Kiitz- 

 ing) Schroeter. {Microloa rosea Kiitz- 

 ing, Linnaea, 8, 1S33, 371; Cryptococcus 

 roseus Kiitzing, Pliycologia generalis, 

 Leipzig, 1843, 149; Protococcus roseo- 

 persicinus Kiitzing, Species Algarum, 

 Leipzig, 1849, 196; Palmella persicina 

 Cohn, Leonhard's Jarhb. f. Mineralog., 

 1864, 606; Pleurococcus roseo-persicinus 

 Rabenhorst, Flora Eur. Algarum, 

 Leipzig, 3, 1868, 28; Bacterium rubesccns 

 Lankester, Quart. Rev. Micro. Sci., 

 IS, 1873, 408; not Bacterium rubescens 

 Chester, Ann. Rept. Del. Col. Agr. Exp. 

 Sta., 9, 1897, 115; Clathrocystis rose.o- 

 persicina Cohn, Beitr. Biol. Pfl., 1, Heft 

 3, 1875, 157; Cohnia roseo-persicina Win- 

 ter, in Rabenhorst, Kryptogamen Flora, 

 2 Aufl., 1, 1884, 48; Schroeter, in Cohn, 

 Kryptogamen-Flora von Schlesien, 3, 1, 

 1886, 151; Planosarcina roseo-persicina 

 Migula, in Engler and Prantl, Die na- 

 tiirlichen Pflanzenfam., 1, la, 1895, 20; 

 Lankastcron rubesccns Ellis, Sulphur 

 Bacteria, London and New York, 1932, 



135.) From Latin roseus, rose-colored 

 and persicum, peach; M.L., peach-col- 

 ored . 



In all probability, Thioderma ruhrum 

 Miyoshi (Jour. Coll. Sci., Imp. Univ. 

 Tokyo, Japan, 10, 1897, 170) is identical 

 with this species. 



Cells: Spherical to ovoid, 2 to 2.5 mi- 

 crons in diameter, up to 5 microns long 

 before cell division. Motile. Polar 

 flagellate. 



Winogradsky {loc. cit.) reports that the 

 cells frequently contain pseudovacuoles. 



Habitat: Mud and stagnant water con- 

 taining hydrogen sulfide and exposed to 

 light; sulfur springs. 



Illustrations: Warming, Videnskab. . 

 Meddel. naturhistor. Foren., Kjoben- 

 havn, 1876, PI. VIII, fig. 3 g; Zopf, Z. 

 Morphol. d. Spaltpflanzen, Leipzig, 1882, 

 PI. V, fig. 8, 13; Winogradsky, Schwefel- 

 bacterien, Leipzig, 1888, PI. II, fig. 9-15; 

 Bavendamm, Die farblosen und roten 

 Schwefelbakterien, Jena, 1924, PI. II, 

 fig. 3. 



Genus VIII. Amoebobacter Winogradsky. 



(Winogradsky, Schwefelbacterien, Leipzig, 1888, 71; Amoebomonas Orla-Jensen, 

 Cent. f. Bakt., II Abt., 22, 1909, 334.) From amoeba, one of the protozoa character- 

 ized by a constantly changing shape, and Greek baktron, rod. 



Purple sulfur bacteria, usually occurring in aggregates composed of many in- 

 dividuals without a characteristic common capsule. Slime formation can, neverthe- 

 less, be observed with very small colonies. With growth of the individual cells, the 

 capsule bursts and the cell mass slowly moves out while the bacteria remain united. 

 The colonies change their shape during growth and in response to environmental 

 influences; the individual cells appear motile and cause the movements of the entire 



