LIST OF PLATES 
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Facing page 
Puate 1X. Flower-clusters of dogwood (Cornus florida), showing a 
highly developed and conspicuous involucre, probably attractive 
to pollinating insects : 5 
Puatre X. Thistle fruits, adapted for Hisoaial by the wad : 
Piare XI. Tree ferns in Ceylon : : . é ‘ 
Piate XU. Improvement of corn. The upper picture shows the 
effect of drying seed corn by artificial heat. The rows near 
the middle grew from kiln-dried seed, the others from ordinary 
seed. The lower picture shows the effect of cross-pollination - 
and of self-pollination on the growth of corn from the seed. 
The two rows of spindling plants at the left grew from seed pro- 
duced by self-pollination, the larger plants of the other rows 
from seed produced by cross-pollination . 
PuateE XIII. Fruiting banana plants. The natural slitting of tlie 
leaves by the wind serves to prevent them from mene blown 
away bodily during tropical storms . 
Puate XIV. Oak saplings springing from a dupe. Oak, giscinat, 
and many other hard-wood trees are most quickly replaced on 
cut-over woodlands by allowing young trees to grow from the 
stumps ‘ . . . . . . 
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