Vascular bundle, 62 
Water content of the soil, 
81 
Water, importance of, 29 
Water, movement of 
plants, 83 
Water plants, 120 
INDEX 255 
in 
Witches’-brooms, 174 
Wood, destruction of by 
fungi, 169 
Xerophyte, 138 
Zoospores, 35, 207 
Zygote, 213 
