GENERAL SYSTEMATIC BACTERIOLOGY 449 



Meyer (1912, p. 5) also used Rhodosarcina as a designation for a 

 section of the genus Sarcina to include those species containing bacterio- 

 purpurin. He includes here the genera Thiocystis, Lamprocystis 

 and Thiocapsa. 



Rhodosphaera. A name proposed by Buchanan (1918, p. 472) to 

 replace the homonym Rhodococcus MoHsch (q.v.). The genus is in- 

 cluded as the third in the tribe Rhodohacterioideae, with the description: 



Cells spherical, non-motile, free not united into families. 



The type species is Rhodosphaera capsulatus (Molisch) Buchanan. 



Bergey et al. (1923, p. 405) followed Buchanan. 



The name is invalid as a generic designation for the bacteria, as 

 the name Rhodosphaera was given by Engler in 1881 to a genus in the 

 family Anacardiaceae among the flowering plants. 



Rhodospira. A name proposed by Meyer (1912, p. 4) for the first 

 section of the genus Microspira with the description "Bakteriopurpurin 

 enthaltende Spezies." 



Rhodospirillum. A generic name used by Molisch (1907, p. 24) 

 to include bacteria containing bacteriopurpurin, without sulfur granules, 

 with cells free, bent in a spiral, actively motile by means of a polar 

 flagellum or cluster of flagella. Two species are described as new 

 Rhodospirillum giganteum Molisch and Rh. photometricum Molisch, 

 and Esmarch's species Spirillum ruhrum is included as Rh. ruhrum (Es- 

 march) Molisch. 



This name was also used by Orla- Jensen (1909, p. 334) to replace 

 the older name Thiospirillum as the twelfth genus of his family Rho- 

 dohacteriaceae. This use of the name is invalid. 



Meyer (1912, p. 3) makes Rhodospirillum the second section of the 

 genus Spirillum with the diagnosis "Spirillen welche Bakteriopurpurin 

 in dem Protoplasten enthalten." He beUeves Molisch's genus Rhodo- 

 spirillum should be thus disposed of. 



Buchanan (1918, p. 473) included the genus as the seventh in the 

 subfamily Rhodohacterioideae with the description "Cells spiral, actively 

 motile by means of polar flagella." The type species is designated as 

 Rhodospirillum ruhrum (Esmarch) Molisch. 

 Bergey et al. (1923, p. 407) followed Buchanan. 

 Rhodothece. A genus of bacteria named by Mohsch (1906, p. 223) 

 to include organisms containing bacteriopurpurin and sulfur granules, 

 cells not united into families, not capable of swarming, each cell 

 surrounded by a spherical or ellipsoidal capsule, cell usually spherical 



