842 MANUAL OF DETERMINATIVE BACTERIOLOGY 



2. Aggregates in the form of three-dimensional masses. 



a. Cells distinctly rod-shaped, and arranged in a net-like structure. 

 Genus IV. Thiodiclrjon, p. 845. 

 aa. Cells not so arranged. 



b. Cells in a common capsule, individuals rather scattered and 

 loosely grouped. 



Genus V. Thiothece, p. 846. 

 bb. Cells in rather dense clumps. 



c. Aggregates embedded in conspicuous common slime capsule, 

 d. Aggregates small, compact, often several of them enclosed 

 together in a common capsule. 



Genus VI. Thiocystis, p. 846. 

 ckl. Aggregates large and solid, later break up into small 

 clusters. 



Genus VII. La/nprocijstis, p. 847. 

 cc. Connnou capsule lacking or very transient. 



d. Aggregates as a whole exhibit amoeboid movements. 

 Genus VIII. Amoehuhacter , p. 848. 

 dd. Aggregates devoid of amoeboid movements. 



Genus IX. Thiopolycoccus, p. 850. 

 II. Cells usually occurring singly. 



A. Cells clearly spiral -shaped. 



Genus X. ThiospirillHin, p. 850. 



B. Cells not spiral-shaped. 



1. Cells irregular, often swollen, distorted, or composed of long, crooked and 



bent rods to filaments. 



Genus XI. Rhahdomonas, p. 853. 



2. Cells regular, spherical to short rods or bean-shaped. 



a. Cells spherical, as a rule non-motile, and each one surrounded by a 

 rather wide cai)sule. 



Genus XII. lihodothece, p. 855. 

 aa. Cells ellipsoidal, ovoid, short rods or vibrios, actively motile. 



Genus XIII. Chromatium, p. 856. 



Genus I. Thiosarcina Winugradsky. 



(Winogradsky, Zur Morphologic und Physiologic der Bacterien, I. Schwefelbac- 

 terien, Leipzig, 188S, 104; Rhodosurcina Orla-Jensen, Cent. f. Bakt., II Abt., 22, 

 1909, 344; Rhodothiosarcina Ellis, Sulphur Bacteria, London and Xew York, 1932, 

 163.) From Greek (lieion, sulfur and Latin sarcina, bundle, packet. 



Individual cells spherical, forming regular cubical packets of sarcina-shape, re- 

 sulting from consecutive division in three perpendicular planes. Packets commonlj' 

 containing 8 to 64 cells. Motility infreciuent. Xon-spore-forming. Contain bac- 

 teriochlorophyll and carotenoid pigments, hence, pigmented purplish to red. Ca- 

 pable of carrying out a photosynthetic metabolism in the presence of hj'drogen sul- 

 fide, cells then store sulfur globules. Anaerobic. 



The type species is Thiosarcina rosea (Schroeter) Winogradsky. 



1. Thiosarcina rosea (Schroeter) Win- 1886, 154; Sarcina sulpharala Winograd- 

 Dgradsky. iSarrina rosea Schroeter, sky, Bot. Ztg., Ji5, 1887, 576; Winograd- 

 Kry])tog. Flora voti Sclilc.sien, 3, \, sky, Zur Morphologic uiid Physiologic 



