HOW NATURE) CREATED THE FIRST PEANTS 77 
water lily, a wide-open one, and you can trace clearly 
the change from stamens to pistil. Indeed, when you 
know all about the flowers you can trace every part, 
from calyx to corolla to stamen and pistil, back to the 
green leaf. Even the anther on the stamen is an un¬ 
folded leaf-blade. 
So, you see, “all parts of the flower have a common 
nature—they are all leaves transformed in various ways 
and combining to fulfil the plant’s chief end—that it 
should produce seeds which will develop into full-grown 
plants and bear next year’s flowers.”—Arthur Thomson. 
All the features which make flowers different one from 
another, color, form, and fragrance, are due to Nature's 
efforts to secure the best possible means for the transfer 
of pollen. 
Because they are wind-pollinated, not insect-pollinated, 
the flowers of the oak are small and modest. The co¬ 
rolla is not formed to attract notice, so it is not vivid 
nor large, if so it would be a hindrance, catching the 
flying pollen and preventing it from reaching the sticky 
surface of the pistil. On most wind flowers the stamens 
hang far out of the corolla on slender threads, “dangling 
in the air, shaken fry every gust.” The pistils, too, pro¬ 
trude ; have you never watched the hazel catkins swinging 
in the breeze, their crimson pistils combing the air for 
drifting pollen? In wind-pollinated plants the flowers 
