SPIRILLACEAE AND NITROBACTERIACEAE 177 



A. Non motile Spirosoma 



B. Motile 



1. Cells rigid, forming a segment of a circle or united into spirals, 



1, 2 or 3 polar flagella Vibrio 



. 2. Cells definitelj^ spiral: 



a. With endogenous spores. Flagella not polar. 



Spirobacillus 



b. With or without endogenous spores. Flagella polar 



Spirillum 



The following generic names have been proposed for spiral 

 organisms. 



Spirillum Ehrenberg, 1830, p. 38 

 Myconostoc Cohn, 1875, p. 183 

 Pacinia Trevisan, 1885, p. 83 

 Microspira Schroeter, 1886, p. 168 

 Pseudospira De Toni and Trevisan, 1889, p. 1018 

 Euspirillum De Toni and Trevisan, 1889, p. 1009 

 Euspirosoma Migula, 1900, p. 955 

 Liquidovibrio Jensen, 1909, p. 333 

 Solidovibrio Jensen, 1909, p. 333 

 Paraspirillum Dobell, 1911, p. 94 

 Vibrio Mueller, 1773, p. 39 

 Spirodiscus Ehrenberg, 1838 

 Spiromonas Perty, 1852, p. 171 

 Spirulina Hueppe, 1886, p. 146 

 not Spirulina Turpin, 1827 

 not Spirulina Cohn, 1853 

 Spirobacillus Metschnikoff, 1889, p. 61 

 Streptospirillum Billet, 1890, p. 24 

 Spirosoma Migula, 1894, p. 237 

 Sporospirillum Jensen, 1909, p. 340 

 The generic name Spirulina is invalid because of prior use 

 for another genus of plants. 



The species of the following genera cannot be identified from 

 the description. Myconostoc, Spirodiscus, Spiromonas, Strep- 

 tospirillum, Spirobacillus, Sporospirillum. 



The following are subgeneric terms: Euspirillum, Euspiro- 

 soma, Pseudospira. 



