575. 240 



581.16 



595.793 



II 



Bees and the Development of Flowers 



"~\ABWIN and Dr Russel Wallace maintain that the bright 

 -*-< colours of flowers are due to insects, and this view has, 

 till recently, been accepted by most biologists. But difficulties 

 become apparent as soon as the methods of insect workers are 

 closely investigated. The result of such investigations has been 

 that some naturalists (among them Mr G. W. Bulman, writing in 

 Natural Science, Aug. 1897) have come to the conclusion that the 

 colours of flowers have arisen quite independently of insects and that 

 they have yet to be accounted for on Darwinian principles. 



A priori, if it be granted that the Darwinian hypothesis affords 

 a satisfactory explanation of other phenomena of the animal and 

 vegetable worlds, it seems unlikely that it should leave the colours 

 of flowers unexplained. Moreover, flowers that are invariably fertil- 

 ised without insect aid are almost all of them dull and inconspicuous. 

 The young cones of the larch are an exception. In these the colour 

 may, possibly, be looked upon as a by-product of the physiological 

 activity of the plant. The more striking blossoms, elaborate in form 

 and coloration, cannot possibly be mere by-products. 



The difficulty of explaining the colours of flowers, though by no 

 means insuperable, is very real. Insects can never produce a new 

 species unless during each journey from and back to the hive they 

 keep to the same sort of flower. That they show a remarkable 

 constancy is undeniable. When at work upon dandelions they will 

 not wander to a neighbouring narcissus. In thus keeping to flowers 

 of the same make, they are consulting their own interest : they can 

 extract the honey with greater speed than if they wandered to 

 flowers of a different build. Frequent practice at the same exercise 

 produces great dexterity of limb and proboscis, and the work goes 

 merrily on. There is but little of the tentative buzzing and recon- 

 noitring that is unavoidable when a bee is investigating an unfamiliar 

 flower. And thus it is to a bee's own interest not to transfer 

 pollen to a flower of a different genus or of different family. But 

 she is often tempted to go from one variety to another, or to a 

 closely allied species, and she does so without scruple. Thus it is 

 just where her constancy might seem most needed that it breaks 

 down. When new varieties are arising, the operation of bees comes 



