VARIOUS MARRIAGE CUSTOMS. 87 



ern flowers come to get at last their brilliant 

 corollas ? 



We must remember that anything which made 

 flying insects visit plants would be of use to the 

 flowers, as promoting cross-fertilisation. Now, as 

 far as we can see at present, before flying insects 

 were evolved in the animal world, there could 

 have been no such things as bright-hued blossoms 

 in the vegetable kingdom. But insects must very 

 early have gone about eating pollen on plants, as 

 they do to this day in many instances ; and though 

 in itself this would be a loss to the plant, yet 

 plants have often found it well worth their while 

 to pay blackmail to insects in return for some 

 benefit incidentally conferred upon them. Again, 

 as the insects flew from plant to plant, they would 

 be sure to carry pollen on their heads and legs ; 

 and they would rub off this pollen on the sticky 

 stigma of the next flower they visited, which 

 would make them on the whole useful and profit- 

 able visitors. So the plants, finding the good 

 cross-fertilisation did them, began in time to bribe 

 the insects by producing honey in the neighbour- 

 hood of their pistils and stamens, and also to at- 

 tract their eyes from afar by means of those allur- 

 ing and brilliantly-coloured advertisements which 

 we call petals. 



I don't mean, of course, that the plants knew 

 they were doing all this; they were unconscious 

 agents. Whenever any variation in the right di- 

 rection occurred by chance, natural selection im- 

 mediately favoured it, so that in the end it comes 

 almost to the same thing as if the plant deliber- 

 ately intended to allure the insect ; and for brev- 

 ity's sake I shall often so word things. 



How did the plant first come to develop, such 



