INDEX 



42X 



Homogeneity of vegetation, 39 

 Homogyne alpina, 120 

 Homologies, 366 

 Honkenya peploides, 67, 239 

 Hordeion murini, 374 

 Hordeum maritimum, 194 



murinum, 374 

 Horizons of vegetation, 347 



soil, 164, 173, 189 

 Hot springs, vegetation of, 203 

 Humicolous plants, 63 

 Humidity, 95, 125 

 factor, 143, 145 



and nitrogen of soil, 145 

 measurement of, 132, 248 

 {See also Relative humidity) 

 Humification, 242 

 degree of, 252 

 number, 253 

 Humulus, 296 



Humus accumulation and acidification, 

 249, 313 

 of, in soils, 245, 248 

 alpine, 251 

 colloids, 162 

 destruction, 247 

 determination of, 252 

 formation, 244, 246, 247, 248 

 forms of, 248 

 horizon, 164, 173 

 materials, 249 

 nitrogen ratio, 248 

 plants, 7 

 raw, 245 



saturated, 162, 250 

 soils, alpine, 163, 312 

 unsaturated, 163, 250 

 Hutchinsia procumbens, 230 

 Hydathodes, 127 

 Hydatophytes, 126 

 Hydrarch succession, 332 

 Hydrogen ion concentration, 166 

 measurement of, 167 

 ions, significance of, 169 

 numbers, 166 

 Hydrogeophytes, 290 

 Hydrohemicryptophytes, 290 

 Hydrophyllum, 252 

 Hydrophyta, 290 



Hydroph3i;es, 290, 361 

 Hydroplaakton, 289, 370 

 Hydrotherophytes, 290 

 Hygrometer, 132 

 Hygromorphy, 125 

 Hygrophytes, 126 

 Hygroscopic water, 212 

 Hylocomium, 292 



loreuvi, 66 



splendens, 9, 124 



triquetrum 116, 124, 125 

 Hyperdispersion, 31, 37 

 Hypericum, 292 



humifusum, 364 



pulchrum, 351 

 Hypnum, 292 



schreberi, 9, 124, 125 

 Hypodispersion, 31, 37 



Idiobiology, 1 



Ilex aquifolium, 86, 90, 93, 186 



district, 355 

 Impatiens, 224, 296 

 Index of soil moisture, 214 

 Indicator plants, 21, 64 

 Indicators, nitrate, 239 



of optimal conditions, 65 

 Indifferent species, 59 

 Indirect action of lime, 182 

 Insolation, adaptations against, 106 



and exposure, 264, 268 

 Inula crithmoides, 192 



ensifolia, 185 



grandis, 329 



viscosa, 190 

 Invasion, centrifugal, 308 



marginal, 308 



of mosses, 307 



of plants, 16 

 Inversion of zonation, 348 



temperature, 87 

 Ionic effects of sodium chloride, 194 



exchange, 179 

 in soils, 163 

 Ions, toxic effect of, 180 

 Ireland, climate of, 95 

 Iris sibirica, 37, 351 



