GENERAL SYSTEMATIC BACTERIOLOGY 425 



"Rods, yellow or white, motile or non-motile, the motile species pos- 

 sessing either mono- or lophotrichous flagella. May or may not form 

 yellow pigment." 



The type species is Phytomonas campestre (Pammel) Bergey. 



Phytomyxa. A generic name used by Schroter (1886, p. 135) for 

 the organisms causing nodules upon the roots of leguminous plants. 

 This organism had previously been named Schinzia leguminosarum 

 by Frank (1879, p. 376). Since the generic name Schinzia (q.v.) was. 

 preoccupied Schroter (1886) gave the name Phytomyxa leguminosarum^ 

 including this organism among the Myxomycetes in the order Phyto- 

 myxini. He also named a similar species from the lupine, Phytomyxa 

 Lupini. He based his inclusion of this genus with Plasmodiophora 

 among the slime molds on the work of PriUieux (1879, p. 98). The 

 plasma-like filaments in the nodules he interpreted as the vegetative 

 growth, and the bacteriods as spores. Beijerinck (1888, p. 758) named 

 this organism Bacillus radicicola. It was again included among the 

 shme-molds a year later by Schroter (1889, p. 7). Frank (1889, 

 p. 338) concluded that the assignment of the organism to the slime 

 molds was incorrect, and that a new generic name should be chosen. 

 He used Rhizohium leguminosarum. More recently this organism has 

 been known by several names, as Pseudomonas radicicola, Bactridium 

 radicicola (Fischer 1903, Lotsy 1907), Bacterium leguminosarum 

 (Smith 1905). Maire and Tison (1909, p. 241) have emphasized the 

 fact that even though the genus Phytomyxa was erroneously included 

 by Schroter among the Myxomycetes this did not invahdate the genus 

 name. 



Phytomyxa is probably technically a vaUd generic name for organisms 

 of the type which cause nodule formation on the roots of legumes if 

 this type is worthy of generic recognition, with the type Phytomyxa 

 leguminosarum (Frank) Schroter. 



However, Winslow et al. (Committee Society of American Bacteriol- 

 ogists 1917) recommended that Rhizohium be recognized as a genus 

 conservandum for this group. In this they have been followed by- 

 Buchanan (1918), Bergey (1923) and others. 



Planococcus. A genus of cocci proposed by Migula (1894, p. 236) 

 who says: Planococcus nov. gen. Die Zellen teilen sich nach 2 Rich- 

 tungen des Raimies wie bei Micrococcus besitzen aber geisselformige 



