482 



Index and Glossary 



Nitrosococcus, 171. 



Nitrosomonas, 171. 



Nobbe, 227, 233. 



Nodules (little swellings that are 

 formed on the roots of legumes 

 through the agency of a certain 

 species of bacteria), depth of for- 

 mation, 259; nature of, 213; on 

 roots of legumes, 210, 212, 217. 



Non-motile bacteria, 19. 



Oidium lactis, 413, 425-427, 444. 



Omelianski, 344. 



Organic acids (sour substances con- 

 taining the element carbon. Car- 

 bonic acid is usually not included 

 among these.), effect of, on rock 

 decomposition, 292. 



Organic matter, destruction of, in 

 water, 67, 81; oxidation of, in ani- 

 mal body, 307; production of ni- 

 trates by, 184; quality of, in water, 

 78; relation of, to denitrification, 

 189. 



Orleans method, 469. 



Oxidation of ammonia, 331, 334. 



Oxygen, relation of bacteria to, 38. 



Ozone (a modification of oxygen, 

 found in minute quantities in the 

 atmosphere, and produced arti- 

 ficially by chemical or electrical 

 methods), 86, 195. 



Pasteur, 5, 11, 49, 115, 169, 390, 

 459. 



Pasteurization (the heating of mater- 

 ials, usually to 140 to 165 Fahr., 

 a temperature sufficient to kill the 

 bacteria themselves, but not their 

 resistant spores), 23, 24, 389-391, 

 472. 



Pathogenic bacteria (capable of caus- 

 ing disease), 23. 



Peat, number of bacteria in, 146. 



Penicillium camemberti, 425, 426. 



Pepsin, 34, 422. 



Peptones (substances akin to al- 



bumoses, derived from the decom- 

 position of proteids), 420. 



Peptonizing bacteria (organisms pro- 

 ducing enzymes that lead to the 

 breaking down of proteids and the 

 formation of albumoses, peptone, 

 amides and ammonia), 418, 425. m 



Permeable, 29. 



Persoon, 466. 



Pfeiffer, 332, 350. 



Phosphate, fertilizers and bacterial 

 activities, 284; lime, 281, 286. 



Phosphates, influence of, on humus, 

 282; relation of, to soil bacteria, 

 281; soil, relation of, to carbon 

 dioxid, 282; soluble, production of, 

 by bacteria, 282. 



Phosphorescence, 35. 



Phosphoric acid, action of, 289; 

 availability of, in bone, 286; availa- 

 bility of, in Thomas slag, 287; in 

 bone, 285; in humus, 283; in manure 

 289; relation of, to soil bacteria, 

 289; solution of, in soil, 281. 



Phosphorus, in humus, 284; inorganic, 

 and organic, 282; relation of, to 

 soil bacteria, 282. 



Photobacteria (bacteria that cause 

 phosphorescence in the media in 

 which they are growing), 35. 



Physiology of bacteria (the chemical 

 changes effected by bacteria in 

 their life processes), 5. 



Pickles, 445, 446. 



Pigments, 35. 



Plant-food, loss of in drainage, 126. 



Plant-food, removal of, to the sea, 

 276. 



Plate methods (the isolation of bac- 

 teria from colonies on gelatin, agar, 

 and similar materials that can be 

 spread out and solidified by cooling 

 on glass plates, or shallow glass 

 dishes), 9. 



Plenciz, 6. 



Popov, 342. 



Port de Salut, 422, 



