INDEX 



315 



vegetation, symmetry in, 298 



zones, 302 

 vernal flowers, 130 

 vertical zonation, 301 

 Vicia faba, 109, 138 

 vicine, 273 

 Viola, 247 

 virgate form, 163 

 viscid disseminules, 243 

 Vitis, 141 

 vixgregarious, 205 

 Volvocacece, 243 



Wagnera, 239 



stellata, 40, 146 

 Wallace, 189 

 water, 5 



adaptation to, 144 

 adjustment to, 38 

 available, 9, 14 

 capacity, 17 

 competition for, 253 

 content, 7, 8, 63 



computation of, 11 



effect of acids and alkalies, 19 



influence of other factors, 9 



influence of precipitation, 21 



influence of soil, 15 



location of readings, 12 



time of readings, 12 

 experimental adaptation to, 153 

 loss, 177 



decrease by rolling of leaf, 

 145 



decrease throua;h leaf position, 

 145 

 migration, 245 

 non-available, 9, 14 

 of the habitat, 7 

 stimuli, 7 

 storage cells, 158, 159 



tissue, 152 



water supply, adaptation to exces- 

 sive, 152 

 adaptation to small, 144 

 increase and storage of, 151 

 upward movement in plant, 55 



weathering, 16, 283 



Wells, 189 



Wiesner, on transpiration, 67 



wilting, 69 



winged disseminules, 242 



wind, 25 



in migration, 245 



witches' brooms, 5 



Wolffia, 167 



woocl fibers, 53 



woody stems, structures of, 53 



xenogamy, 124 

 xerophytes, 155, 156, 164 



general features of, 156 



leaf, 157 



stem, 162 

 xerophytic formations, 233 

 xylem, 42, 52 



zonation, 220, 294 



bilateral, 300 



kinds of, 299 



radial, 299 



relation between alternation and, 

 289 



vertical, 301 

 zones, 212 



due to growth, 295 



due to migration and ecesis, 295 



due to physical factors, 297 



due to reaction, 296 



vegetation, 302 

 zoochores, 245 

 zoophilous flowers, 125, 126 

 Zostera, 125 

 zymogen, 100 



