In a freshly opened blossom each stamen is bent over, as you see they are bent over in the picture (Fig. [233]).
Their dust boxes are caught in little pockets of the flower cup. When a bee lights on a flower (Fig. [234]), the jar causes the dust boxes to spring from the pockets with so much violence that the pollen is shaken over the body of the visiting bee, which is sure to leave some of it on the pistil of the next flower.
Fig. 232
Some flowers take special care to prevent their pistils from being dusted with pollen from the dust boxes of the same blossom. The fireweed bears such blossoms as these.
Fig. 233
In Fig. [235] you see that the stamens of the fireweed are large and ripe, and ready to shed their pollen; but the pistil is bent sideways, pushing its closed tip quite out of the corolla, and out of reach of any pollen from a neighboring stamen.
| Fig. 234 | Fig. 235 | Fig. 236 |
Fig. [236] shows you another blossom from this same plant. The stamens have shed their pollen, and are quite dry and withered; but its pistil has straightened itself, and spreads out its four tips so as to receive the pollen from another flower.