INDEX 



439 



Xeromorpkic adaptations of halophytes, 

 192 

 structure, 126 



of ericaceous heath, 132 

 Xeromorphy, 125, 127 

 Xerophile climate, 94 

 Xerophytes, 126, 361 

 transpiration of, 127 



Yarding places, 277 



Zannichellia pedicellata, 374 

 Zea niais, 235 

 Zinc soils, 191 



associations of, 63 



plants of, 191 

 Zizyphus, 311 

 lotus, 275 



Zonal communities, 345 

 Zonation, 345 



algal, 346 



altitudinal, 347 



inversion of, 348 



littoral, 346 



of saline communities, 197 



of vegetation and osmotic value of 

 soil solution, 206 

 Zones, altitudinal, 345, 346, 347 



climatic, 94 



concentric vegetation, 345 



determination of, 348 



great life, 345, 366 



latitudinal, 94 



temperature, 93 



vegetative, in C^vennes, 348 

 Zostera, 194, 374 

 Zuider Zee, drying up of, 328 

 Zygonium, 371 



ericetorum, 309 



