116 THE NATURE-STUDY OF PLANTS 
will suppose that it is quite early on a fine warm 
sunny summer morning, we shall find five of the 
stamens ripe and close around but slightly above 
a the unopened §stig- 
mas, which, however, 
soon push through 
and surmount them; 
that is the first stage. 
A few hours later the 
stigmas will begin to 
open, and the anthers 
or heads of the ripe 
stamens will begin to 
drop off, as they bend 
Fic. 46.—Herb Robert. Diagram offour @WaY from the centre 
pollination stages (magnified, and of the flower: that 
only 5 out of the 10 stamens shown). . 
Fes is the second stage. 
Still later the anthers 
of the other five stamens, which up till now have 
remained more or less hidden, will move towards 
the centre and shed their grains; that is the third 
stage. Lastly, they too will drop their anthers and 
there will be only the sepals and the headless stamens 
or filaments surrounding the pistil in the centre of 
the blossom. 
Now we should notice that all the time that the 
stamens have been shedding their sticky grains, the 
stigmas have either been closed or else expanded 
above them, and as pollen, like other things, does not 
fall upwards, all the plans are in favour of a cross. 
As a matter of fact, the grains are much too oily 
and sticky to fall at all, even when the blossom hangs 
down at night; but, as pointed out in Chapter IV., 
there are, at any rate theoretically, other possibilities 

