THE FLOWERS OF BRAZIL 



flowers was evolved, and presently there were whole groups of 

 insects which had actually transformed their bodies with a view to 

 seeking the new form of nourishment. The bees grew baskets on 

 their legs, which they filled with pollen, and a trunk or proboscis 

 with which to suck up the nectar, and the butterflies, which out- 

 wardly resembled the flowers, were also provided with a long pro- 

 boscis, which gradually assumed such a form that the insect was 

 able to feed only on the nectar of flowers. 



But the reciprocal adaptation of the flowers had to be even more 

 elaborate. For if all the insects were to visit all the flowers, they 

 would, as a rule, convey the pollen of one species to the stigma 

 of another, and only by an unusual coincidence would an insect 

 fly direct from one plant to another of the same species. But since 

 fertilization cannot occur unless the pollen is conveyed to the stigma 

 of the same species, the plant would obviously find it advantageous 

 to specialize in respect of certain kinds of visitors. Once it had done 

 so, the selected insect would visit only plants of the same species, 

 dusting itself over with pollen in one flower, and brushing it off" 

 upon the stigma of another, and thereby fertihzing the latter. They 

 would — so to speak — put into only those harbours in which their 

 wares were valued. And the insects too would profit by such a 

 restriction, for they might be sure that their special flowers would 

 not be visited by all sorts of other insects, whereby the cup would 

 often be emptied before they arrived. Here again, then, we have an 

 example of the distribution of food according to an all-seeing plan, 

 and the creation of a harmonious work of art, all the parts of which 

 are mutually geared together. We see, too, that in virtue of such 

 reciprocity living creatures which apparently are quite unrelated may 

 be bound together by bonds of life and death. For example, it may 

 happen that in a whole countryside an important plant, such as 

 clover, is dying out, because it no longer produces seed. On closer 

 examination it appears that the seed cannot be produced because 

 the flower has specialized with a view to fertilization by the bumble- 

 bees, and that these have disappeared from the neighbourhood. We 

 find the cause of their disappearance in the depredations of the 

 field-mice, which have destroyed the subterranean nests of the bees, 

 and presently we discover that the mice have increased because all 

 the owls and buzzards have been shot. And this crime has been 

 avenged by the disappearance of the clover. 



Most of the insects which have been chosen as the fertilizing agents 

 of flowers have one thing in common : a hairy body. With their 



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