CONTENTS 



SECTION IX 



CLASS IV. PSYCHROPHYTES. FORMATIONS ON 



COLD SOIL 



CHAPTER PAGE 



LXV. Climatic Conditions in Subglacial Fell-fields . 248 



LXVI. Adaptation of Species in Subglacial Fell-fields 251 



LXVII. Subglacial Fell-field Formations . . . 256 



SECTION X 



CLASS VII. PSAMMOPHYTES. FORMATIONS ON SAND 



AND GRAVEL 

 LXVIII. Oecological Factors. Formations . . . 262 

 LXIX. Shifting, or White, Sand Dunes . . . 263 



LXX. Stationary, or Grey, Sand-dune. Sand-fields. 

 Dune-heath. Dune-bushland. Dune-forest. 

 Other examples of Psammophilous Vegetation 265 



SECTION XI 



CLASS IX. EREMOPHYTES. FORMATIONS ON DESERT 



AND STEPPE 



LXXI. Oecological Factors. Formations . . . 273 



LXXII. Desert 274 



LXXIII. Shrub-steppe 278 



LXXIV. Grass-steppe 281 



LXXV. Sibljak 288 



SECTION XII 



CLASS VIII. CHERSOPHYTES. FORMATIONS ON 



WASTE LAND 



LXXVI. Waste Herbage 



LXXVII. BusHLAND ON Dry Soil .... 



289 



291 



SECTION XIII 



CLASS X. PSILOPHYTES. SAVANNAH-FORMATIONS 



LXXVIII. Savannah-formations 293 



LXXIX. Thorny Savannah 293 



LXXX. True Savannah 295 



LXXXI. Savannah-forest 299 



