230 



INDEX 



Arsenic, occurrence in soil, 206 

 Aristotle, 3 



Ash, requirements of bacteria, 59 

 Atmosphere in soil formation, 76 

 Autotrophic bacteria, 56 

 Azotobacter chroococcum, 148 

 Azotobacter, condition of growth, 



143 



discovery of, 141 



energy requirements 

 145 

 food requirements 



Azotobacter 



Azotobacter 



of, 144, 



Azotobacter 



of, 144 



Azotobacter 



147 



Azotobacter 



on, 209 

 Azotobacter 



carbonate 

 Azotobacter 



on, 189 

 Azotobacter 



144 

 Azotobacter 



on, 1 44 

 Azotobacter 

 Azotobacter 



151-155 

 Azotobacter 

 Azotobacter 



of, 148 

 Azotobacter 



fixation, 

 Azotobacter 



149, 150 



Azotobacter 

 142, 143 



Azotobacter 



how fixes nitrogen, 



influence of arsenic 



influence of calcium 

 on, 142, 143 

 influence of cellulose 



influence of lime on* 



influence of nitrates 



morphology of, 148 

 nitrogen fixed by, 



occurrence of, 142 

 pigment production 



relation to nitrogen 

 170 

 soil inoculation with, 



variation with depth, 

 vinelandii, 148 



Azofication, defined, 140 



B 



Bacillus, 23 



Bacillus, denitrificicans, 133 

 Bacillus, Ellenbachensis, 141 

 Bacillus, mycoides, 1 1 3 

 Bacillus, prodigiosus, 50 

 Bacillus, pyocyaneus, 50 

 Bacillus, radicicola, 158 

 Bacillus, subtilis, 113 

 Bacteria, antiquity of, i 

 Bacteria, are plants, 1 3 

 Bacteria, on animals, 15, 16, 17 

 Bacteria, ash requirements, 59 

 Bacteria as scavangers, 2 1 

 Bacteria, a$ soil formers, 18, 19, 



20, 78 

 Bacteria, autotrophic, 56 

 Bacteria, carbon requirements, 57 

 Bacteria, chemistry of, 42-52 

 Bacteria, classification of, 36-41 

 Bacteria, definition of, 14 

 Bacteria, discovery of, i 

 Bacteria, food requirements, 54- 



61 

 Bacteria, heterotrophic, 56 

 Bacteria, how studied, 42 

 Bacteria, importance of, 97 

 Bacteria, in dairy industry, 21 

 Bacteria, in milk, 1 5 

 Bacteria, in plants, 1 6 

 Bacteria, in soil, 14 

 Bacteria, in water, 14, 15 

 Bacteria, influence of cold on, 64 

 Bacteria, influence of electricity 



on, 67 



