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the; story of the; oak tre;e; 
open early in the Spring, before the foliage leaves grow 
big enough to interfere with the flight of the pollen. 
Wind-borne pollen is light as dust, and Nature has to 
provide plenty of it, for a single grain flying on the 
wind has a very slight chance of finding the pistil of a 
flower of its own kind. In the pine tree Nature has made 
for each pollen grain two little bladders the better to 
float in the air. 
There is wind-borne pollen and there is water-borne 
pollen; the grasswrack of the sea, the weeds in the mill¬ 
pond depend upon the water to carry their pollen from 
plant to plant, and Nature shapes their flowers so that 
wind and water may serve their pollinating purpose 
easily. And all the time our insect-pollinated flowers are 
doing what they can to attract their winged or their 
crawling friends. Have you ever seen a barberry hedge, 
with its red berries nodding their jolly little heads at 
Christmas time? The barberry flowers are so eager for 
cross-fertilization, so afraid the pollen grains will escape 
them, that their stamens spring forward and close over 
anything touching the inside of their base. Where a 
flower has no corolla, the calyx, after the bud has un¬ 
folded, often takes upon itself the form and duties of the 
corolla. It becomes brighter in color, its petals grow 
silky to the touch, like the marsh-marigold and purple 
