318 
ciduous, 265, 270; evergreen 
coniferous, 230, 265, 273 ; ground- 
veg. of, 266 ; larch-, 274 ; natural, 
267 ; oak-, 229, 269; pine, 273; 
scar-, 269 
Wood-sorrel. 
Wormwood, 42 
Wounds, 140 
See Ozalis 
Xerophilous tropophytes, 58, 62 
Xerophytes, 29, 30, 36, 74, 77, 89; 
air-spaces in, 40; palisade-tissue 
in, 41, *72; cuticle of, 40; 
development of hairs and scales 
in, 39, of sclerenchyma in, 41, 
*43 ; evergreen-, 39 ; mucilage in, 
*41; position of leaves in, 46; 
size of leaves in, *39; oil in, 42; 
water-storing tissue in, 41 
Xerophytic annuals, 59; chars., 30, 
36, 58, 60, 61; conditions, 33, | 
BRITISH PLANTS 
229, 272; birch, 229, 271; de- | 
effect on form of leaf, 38, of stem, 
36 ; factors, 32, 35; forms of leaf 
and shoot, 42; structures in 
leaves, 39, 40 ; regions, 35, 77, 89; 
tendencies, 39 
Xylem, *45 ; in aquatics, 49 
Yellow bird’s-nest (see Monotropa) ; 
rattle (see Rhinanthus) ; water-lily 
(see Nuphar) 
Yew: leaf-mosaic, 68; succulent 
seeds, 196 ; Irish, origin of, 205 
Yucca, 133 
Zannichellia, 55 
Zea Mais, 147, 148 
Zones, 226 
Zoning: of aquatics, 236; of the 
reed-swamp, 242 ; of seashore pls., 
278, 283 ; of seaweeds, 276 
Zostera: leaf, 50; pollination, 166, 
276 
