47 



154. Bacillus ruber Plymouth: good growth; vigorous evolution of gas 



on addition of acid; nitrate content greatly diminished; 



Strong formation of nitrite. 



155. Bacillus rubidus: good growth; no evolution of gas on addition of 



acid; nitrate content unchanged; 



No formation of nitrite. 



156. Spirillum rubrum: moderate growth; no evolution of gas on ad- 



dition of acid; nitrate content unchanged; 



No formation of nitrite. 



157. Bacterium rugosum: good growth; vigorous evolution of gas on 



addition of acid; nitrate content greatly diminished; 



Strong formation of nitrite. 



158. Bacillus ruber of Kiel: good growth; vigorous evolution of gas on 



addition of acid; nitrate content greatly diminished; 



Strong formation of nitrite. 



159. Spirillum Rugala: moderate growth; no evolution of gas on addition 



of acid; nitrate content unchanged; 



No formation of nitrite. 



160. Bacterium rubilum: fair growth; no evolution of gas on addition of 



acid; nitrate content unchanged; 



No formation of nitrite. 



161. Bacillus ruminatus: good growth; no evolution of gas on addition 



of acid; nitrate content unchanged; 



No formation of nitrite. 



162. Bacillus rutilus: good growth; moderate evolution of gas on ad- 



dition of acid; nitrate content slightly diminished; 



Weak formation of nitrite. 



163. Bacillus rutilensis: fair growth; moderate evolution of gas on 



addition of acid; nitrate content slighlty diminished; 



Weak formation of nitrite. 



164. Spirillum serpens: moderate growth; no evolution of gas on the 



addition of acid; nitrate content unchanged; 



No formation of nitrite. 



165. Bacillus silvaticus: good growth; vigorous evolution of gas on 



addition of acid; nitrate content greatly diminished; 



Strong formation of nitrite. 



166. Bacillus simplex: good growth; vigorous evolution of gas on ad- 



dition of acid; nitrate content greatly diminished , v 



Strong formation of nitrite. 



167. Vibrio saprophilus: good growth; vigorous evolution of gas on 



addition of acid; nitrate content greatly diminished; 



Strong formation of nitrite. 



168. Micrococcus sordidus: moderate growth; slight evolution of gas on 



addition of acid; nitrate content diminished; 



Weak formation of nitrite. 



169. Bacillus luteus sporogenes: good growth; no evolution of gas on 



addition of acid; nitrate content unchanged; 



No formation of nitrite. 



