Flowers 
From that distant time until to-day every change in 
colour or in form has had to be exposed to the insect’s 
eye. Those changes which found most favour have 
been perpetuated. 
In this process there is nothing at all more mysterious 
than the selection exercised by those nurserymen who 
produce yearly new varieties of turnips or potatoes, but 
it is thé insects who select and discard (see p. 285). 
Not long ago the scientific world was alarmed and 
disturbed by a certain botanist, who declared that insects 
were not attracted by colour but by scent. 
Proof, though not in the least required by any of 
those who had studied the question, was very soon forth- 
coming. When one single petal of a composite could 
attract bees, it was of course obvious that neither scent 
nor the shape of the flower, but colour alone, was the 
important point. 
An observation of Dr. Ridley’s is too interesting to 
leave out ; it reminds us of certain Athenian birds which 
pecked at Apelles’ pictures. 
Dr, Ridley, when passing through the Suez Canal, 
happened to be in the smoking-room of the steamer, 
which was decorated with white enamelled tiles on 
which flowers were represented. Some of these were 
“cup-shaped, more or less resembling a tulip,” and the 
alternate ones were conventional composites. Certain 
“humming-bird hawk” moths were in the smoking- 
room, and he noticed that they were trying to probe 
the mouths of these conventional flowers. As they 
had no scent of any sort or kind, it is clear that the 
moths were attracted by the colour.” 
But this would never have been doubted by any 
one who had taken the trouble to watch for insect- 
visitors on wild plants when growing in their natural 
homes. : 
nts 
