GENERAL SYSTEMATIC BACTERIOLOGY 399 



The organism is termed Bacterium nitrohader by Migula (19C0, p. 

 514). 



The name is rejected by Erwin F. Smith (1905, p. 162). 



Beijerinck (1914, p. 109) in a paper on nitrification states that the 

 organisms present include 



Nitrohader oUgotrophum — Nitrohader polytrophum, das Nitratferment selbst. 

 1) Im nitratierenden, meist unbeweglichen Zustand als N. oligothrophum. im 

 saprophytischen oft beweglichen nicht nitratierenden Zustand, als A^. polytro- 

 phum, zu bezeichnen. Die beiden Formen miissen als physiologische Arten 

 bezeichnet werden und verhalten sich zu einander als Modifikationen und nicht 

 als Mutationen. Der Uebergang findet wie der Pfeil andeutet, nur in eine 

 Richtung statt. 



Just what nomenclatural recognition should be given these names 

 of Beijerinck is somewhat conjectural. Probably Nitrohader oligo- 

 trophum may be regarded as the first use of the generic name Nitro- 

 hader in a binomial. 



Winslow et al. (1907, p. 552) recognized the genus with the following 

 description: 



Cells rod-shaped, non-motile, not growing readily on organic media or in the 

 presence of ammonia. Cells capable of securing growth energy by the oxida- 

 tion of nitrites to nitrates. 



Winogradsky named no species, although he described one. It might be 

 termed Nitrohader Winogradskyi and made the type species. 



The genus was placed in the family Nitrohader iaceae. Substantially 

 the same diagnosis was used by Buchanan (1918, p. 180) the Conmiittee 

 (1920, p. 202), and Bergey et al. (1923, p. 34). 



The genus is here considered vahd, and the type species Nitro- 

 hader oUgotrophum Beijerinck (Nitrohader Winogradskyi Committee). 



Nitrobactereae. A variant spelling of Nitrohacterieae q.v. used by 

 Castellani and Chalmers (1919, p. 932), by Winslow et al. (1920, p. 

 201) and by Bergey et al. (1923, p. 31). 



Nitrobacteriaceae. A family name proposed by Buchanan (1917, 

 p. 349) for the fourth family of the Euhaderiales The diagnosis (1918, 

 p. 180): 



Cells spherical or rod-shaped, motile or non-motile, not growing on ordinary 

 laboratory media in the presence of organic matter. Securing growth energy 

 primarily by the oxidation of ammonia to nitrites or of nitrites to nitrates. 



Three genera were included, Nitrosomonas, Nitrohader and Nitro- 

 sococcus. 



