LIFE-HISTORY OF THE HERB ROBERT 113 
Now if we look at a plant in flower we shall see 
that in the daytime the blossom stands almost straight 
out, but when night comes its stalk bends so that it 
hangs downwards. Pretty and suggestive as the 
position is, the flower nevertheless is not asleep in 
our sense of the word, but it is protected in this way 
from cold and damp. It would, for instance, be a 
disaster for the pollen grains to be bathed in dew: we 
should observe, too, that the flower is not so widely 
open as during the day, and the partial closing gives 
additional protection to the reproductive organs, 
the stamens and pistil. 
Before dealing with them, however, we should note 
that there is no vegetative propagation in the Herb 
Robert ; its reproduction is effected entirely by seeds. 
The flowers are produced on long leafy stems, and 
the joints upon which both leaves and flower-stalks 
are inserted are distinctly swollen, a feature that is 
brought out well in the frontispiece : they contain a 
good deal of starch. Usually the blossoms are pro- 
duced in pairs, but very occasionally one comes across 
three together. 
Around the petals, on the outside are five sepals 
with many long glandular hairs; on the inside are 
ten stamens, and they surround the pistil in the centre, 
which is barely visible when the flower first opens. 
The pollen grains can be seen quite easily with a 
lens, but as it is not possible to see as much as one 
wishes without a microscope, I have illustrated them 
on a large scale by way of a help. 
They are not round like a marble, but they have 
five slight depressions on the surface and three little 
excrescences: I may mention, too, that they are 
yellow, as is very frequently the case, although, as a 
