894 



INDEX OF SUBJECTS 



Starch, as a source of energy, 561 



decomposition of, 461 

 Starch-zinc iodide reagent, 67 

 Staurastrum, 229 



Steam, as an agent of partial steriliza- 

 tion, 746, 748 

 Stemphylium, 256, 258, 260, 265, 490 

 Sterilization of soil, 641 



and solubilization of minerals, 655 

 Stichococcus, 224, 228, 233 

 Stichotricha, 336 

 Stigonema, 224, 227 

 Stigonemaceae, 227 

 Stilbaceae, 3, 256 

 Stimulation of bacteria by antiseptics, 



756 

 Straw, bacteria in, 30 

 composition of, 428 

 decomposition in soil, 684, 704 

 influence of, upon the growth of 

 plants, 516 

 Streptococcus, 58 



pyogenes, 208 

 Streptothrix, 287, 288 

 Strombidium, 336 

 Strophostyles, nodule formation by, 



135, 137 

 Stubble, composition of, 428 

 Slylonychia, 336 

 Sty s anus, 257 

 Sugar-beet nematode, 348 

 Sulfate-reducing bacteria, 174, 188 

 Sulfate reduction, 188-189, 556 

 Sulfates, as sources of oxygen for 

 anaerobic bacteria, 420 

 reduction of, by bacteria, 610-612 

 reduction of, and energy utilization, 

 420 

 Sulfide bacteria, 79, 398 

 Sulfides, oxidation of, 604 

 Sulfur bacteria, 59, 78-91, 399 

 Sulfur, chemical oxidation of, 603, 604 

 energy utilization in the oxidation of, 



397 

 liberation in decomposition of pro- 

 teins, 602, 612 

 oxidation of, by autotrophic bac- 

 teria, 605-609 



Sulfur, oxidation of, by heterotrophic 

 organisms, 604 

 oxidation of, in soil, 540, 602, 605 

 presence of, in plants and in soil, 601 

 reduction of, 610 

 sources of, in soil, 600 

 transformation of, by microorgan- 

 isms, 600-616 

 use of, for control of soil-born dis- 

 eases, 816, 832 

 Sulfur-phosphate composts, 88, 614 

 Sulfuric acid, formation of, by bac- 

 teria, 90, 608 

 Summer bacteria, 32 

 Sweet pea, nodule bacteria of, 136 

 Symbiosis, between bacteria and legu- 

 minous plants, 122-140, 804 

 between bacteria and non-legumi- 

 nous plants, 105 

 Symbiotic action, between Azotobacter 

 and other bacteria, 121, 560, 641 

 between Azotobacter and algae, 121, 



232 

 in cellulose decomposition, 201 

 in mycorrhiza, 280 

 Symbiotic nitrogen fixation, chemistry 



of, 591 

 Symphyla, 355, 357 



Symplastic stage in bacterial develop- 

 ment, 57 

 Syncephalis, 249 

 Syncephalastrum, 249 

 Synchitrium, 236, 763, 808, 814 

 Synechoccus, 226 

 Synedra, 227 

 Synsporium, 255 

 Synthetic agar, 16 



Systematic position of actinomyces, 

 287 



Tachinidae, 356 



Tap water gelatin, 16 



Tardigrada, 342, 354 



Tarsonemidae, 355 



Tartaric acid as a source of energy, 411 



Taurine, 614 



Tellurates, reduction of, 303, 556 



