THE FLOWERS OF MAY. 139 
are white and some are yellow. All of them have 
exquisite pencillings of color which probably serve as 
guides to the insects which visit them. They have 
elaborate contrivances to secure cross-fertilization, con- 
trivances so elaborate that we are led to believe that we 
are witnessing almost the maximum development of the 
insect-fertilizing idea which has been such a prominent 
feature of modern botanical thought. For, besides the 
conspicuous blossoms, which appear early, there are 
others produced later, which never open, in which petals 
are absent or rudimentary; but these are fertilized in 
the bud and are much more prolific than the ordinary 
flowers, though they are apt to escape observation from 
their manner of growth. As Massee puts it: ‘The 
whole structure of the (conspicuous) flower shows that 
self-fertilization was almost impossible, and that the visits 
of insects were indispensable, yet .all these elaborate 
arrangements have not prevented the violets from evolv- 
ing something even more effectual and at the same time 
more economical in connection with fertilization, and in 
reality the old-fashioned colored flower, evolved for aid- 
ing insect-fertilization, is now of no use to the plant. 
But, when a structure is evolved, it cannot be at once 
arrested, even when completely superseded and useless, 
and this is the condition that most of the violets now 
find themselves in, encumbered with an old effete type 
of arrangement for securing insect-fertilization. The 
