PLANTS OF HEDGEROWS AND WALLS 339 



climbing organs ; also those with fruits dispersed by 

 animals, especially birds. 



Examine such a hedgerow and draw to scale a transect 

 passing through the above-mentioned zones and indicate 

 on it the species met with, as in Fig. 218. 



Make lists of the species found in each zone and carefully 

 compare the different forms. 



Study the changes that occur throughout the year, e.g. : 



Winter. The deciduous and evergreen habits ; branch- 

 systems ; bark of trees ; winter-buds ; protection ; 

 leaf-scars. 



Spring. Nature of bud-scales ; opening buds ; folding 

 of leaves and their modes of growth ; spring tints ; 

 characteristics of spring flowers ; wind-pollination ; 

 plants with storage organs, tuberous roots, rhizomes, 

 bulbs. 



Summer. Leaf-mosaics ; comparisons of stems and 

 leaves ; flowers and their insect-visitors. 



Autumn. Fruits and fruit-dispersal ; autumnal tints ; 

 leaf-fall ; roads as highways for fruit-dispersal. 



Many examples of organs adapted for special purposes 

 will be found, and the following should be studied : 



(1) Shrubs with thorns and prickles : 



(a) branch-spines Hawthorn (Fig. 219, 1), Black- 



thorn, Gorse. 



(b) prickles Roses, Brambles, Gooseberry (prickles 



on the leaf-base). 



(c) leaf-spines Holly and Barberry 1 (Fig. 219, 2, 3, 4). 



1 The Barberry has two kinds of shoots : (a) long shoots bearing 

 leaves reduced to branched spines (Fig. 219, 2 and 4, l.s) ; in the 

 axils of these arise (b) dwarf shoots (Fig. 219, 2, d.s) bearing several 

 simple foliage-leaves, each having a joint near the base (Fig. 219, 

 3. ;') 



Y 2 



