INDEX 



425 



Molinietum, 37, 59, 318, 375 



caricetosum hostianae, 46 



coeruleae, 332 



tomentosae, 316 

 Molinion, 239 

 Montia minor, 353 

 Moor peat, 251 

 Mosaic communities, 30, 345 

 Moss associations, 307 



seres, 335 

 Mowing, effect on vegetation, 285 

 Mucor, 237, 309 

 Mughetum, 61 

 Mull, 250, 252 

 Munthe's periods, 339 

 Muscari botryoides, 91 

 Mycorhizal fungi, 6 

 Mycotropic species, 63 

 Mykogene puccinoides, 244 

 Myosotis collina, 64 

 Myosurus, 353 

 Myriophyllum alternifolium, 110 



verticillatum, 374 

 Myrmecodia, 296 

 Myrlus, 174 



N 



Najas, 290 

 Nanism, 125 



Nanocypereto-Polygonetalia, 371 

 Nanocyperion, 364 



fiavescentis, 364 

 Nanophanerophytes, 293, 295, 297 

 Nanophylls, 296 

 Nardeta, 365 



Nardeto-Plantagetum alpinae, 365 

 Nardetum, 24, 156, 275, 323 

 Nardion, 365 

 Narduretia gypsacea, 186 

 Nardzirus, 376 

 Nardus, 24, 250, 291 



grassland, 273, 347 

 Nasturtium, 98 

 Neottia, 63 



nidus avis, 69 

 Neutral species, 316 

 Neutrophilous plants, 167 

 New Caledonia, red soils of, 190 

 Nigella saliva, 99 



Nigrilella, 24 



Nitella flexihs, 109, 110 



Nitrate bacteria, 237 



formation, 237 



indicators, 239 



test for, 238 

 Nitrification, 237 



capacity, 237 



in forests, 237 

 Nitrifying bacteria, 236 

 Nitrobacter, 237 

 Nitrogen fixation, 235 



of soil, 145, 248 

 Nitrophiles, 63 

 Nitrophilous bark associations, 241 



plant communities, 239, 240, 241, 277, 

 Nitrosococcus, 237 

 Nitrosomonas, 237 

 Nitschia putrida, 195 

 Normal biological spectrum, 298 

 Nostoc, 309 



N. S. quotient, 143, 246, 248, 257, 258 

 map of Europe, 258 

 map of U. S., 144 

 Nuphar, 374 

 Nutritive substances of soil, 181 



salts and plant communities, 179 



O 



Oak forests, 324 

 Ocean currents and winds, 95 

 Odontoschis7na denudatum, 89 

 Oedogonium, 179 

 Oidium, 309 



Oil content, higher with higher temper- 

 atures, 89 



formation in trees, 89 



preservative against cold, 89 

 Oligotrophic waters, 76 

 Onarga biennis, 328 

 Onobrychis, 242, 292 



caput gain, 68 

 Ononidetum angustissimae, 153, 327 

 Ononis angustissima, 153 



pubescens assn., 376 



repens, 59 



spinosa, 67 



tournefortiana, 153 

 Onopordon, spp., 276 



