878 



INDEX OF SUBJECTS 



Energy transformation in the metabo- 

 lism of microorganisms, 384-426 

 transformation in the soil, 425 

 utilization by autotrophic bacteria, 



384, 387 

 utilization by heterotrophic bacteria, 



384, 704 

 utilization by nitrogen-fixing bac- 

 teria, 566 

 utilization, efficiency of, 415 



Enrichment culture method, 54, 215 



Environmental conditions, influence of, 

 on symbiotic nitrogen fixation, 

 597 



Entosiphon, 334 



Enzymes of microorganisms, 371, 

 436 



Eparidaceae, mycorrhiza formation 

 by, 271 



Epicoccum, 257 



Epistylis, . 336 



Equilibrium, between carbon and ni- 

 trogen in soil, 702, 704 

 microbiological, in soil, 6, 738-740, 



757, 764, 767 

 theory of symbiotic nitrogen fixation, 

 590 



Ericaceae, mycorrhiza formation by, 

 271, 272, 273, 276, 281, 283 



Errors in plate counts of numbers of 

 microorganisms, 24 



Erythrosine stain for soil bacteria, 8 



Ethyl alcohol, formation of, by bac- 

 teria, 178 



Euasci, 251 



Euastrum, 229 



Eubacteria, 58, 78, 92 



Euglena, 315, 317, 334 



Euglenaceae, 215 



Euglypha, 332 



Euglyphidae, 332 



Eumycetes, 236, 246 



Euplotes, 336 



Eutreptia, 334 



Eulylenchus, 350 



Evolution in plants, 273 



Exhausted soils, 709 



Facultative anaerobic bacteria, 160 

 autotrophic bacteria, 59, 96, 101, 399 

 Fairy rings, 262, 293 

 Fat-splitting bacteria, 204 

 Fat utilization, by actinomyces, 297 

 by fungi, 242 



Fats in soil, 463, 671 



Fauna of soil, 341-363 



Feces as a source of bacteria in soil, 

 29, 176 



Feldspars, decomposition of, by bac- 

 teria, 646 



Fenugreek, nodule bacteria of, 136 



Fermentation, 385, 413 



Fementation of nitrates (see Denitri- 

 fication) 



Ferrous sulfate, as reducing agent, 

 171 



Fertilizers, influence of, on biological 

 activities in soil, 733, 788 

 influence of, on soil reaction, 635 



Filamentous fungi (see Fungi) 



Fixation of nitrogen, 103, 558 



Fixative agents, 323 



Flagellata, 215, 230, 313 



Flagella staining, 132 



Flagellates in soil, 3, 47-50, 326, 328 



Flagellation of nodule bacteria, 132 



Flatworms, 341, 345 



Fleming's solution, 346 



Fluctuation of bacteria in soil, 32 



Flukes in soil, 341,345 



Fluorescent bacteria in the soil, 154 



Forest soils, formation of humus in, 

 694 

 occurrence of algae in, 224 



Formaldehyde as intermediary prod- 

 uct in CO2 assimilation, 403 



Formic acid, formation of by bacteria, 

 414, 440 



Formicidae, 358 



Fragillaria, 227 



Fredericia, 354 



Free energy, 386 



Free-living nematodes in soil, 348 



