THE ORIGIN OF FLOWERS 199 



direction of utility. But this is exactly what we call, after Darwin 

 and Wallace, Natural Selection. 



We have, however, in the history of flowers, a means of 

 demonstrating the reality of the processes of selection in two other 

 ways. In the first place, it is obvious that no other interpretation 

 can be given of such simultaneous mutual adaptations of two 

 difierent kinds of organisms. If we were to postulate, as Nageli, for 

 instance, did, an intrinsic Power of Development in organisms, which 

 jjroduces and guides their variations, we should, as I have already 

 said, be compelled also to take for granted a kind of pre-established 

 harmony, such as Leibnitz assumed to account for the correlation of 

 body and mind : plant and insect must always have been corre- 

 spondingly altered so that they bore the same relation to each other 

 as two clocks which were so exactly fashioned that they always kept 

 time, though they did not influence each other. But the case would 

 be more complicated than that of the clocks, because the changes 

 which must have taken place on both sides were quite difierent, and 

 yet at the same time such that they corresponded as exactly as Will 

 and Action. The whole history of the earth and of the forms of life 

 must, therefore, have been foreseen down to the smallest details, and 

 embodied in the postulated Power of Development. 



But such an assumption could hardly lay claim to the rank of 

 a scientific hypothesis. Although every grain of sand blown about 

 by the wind on this earth could certainly only have fallen where it 

 actually did fall, yet it is in the power of any of us to throw a hand- 

 ful of sand wherever it pleases us, and although even this act of 

 throwing must have had its sufficient reason in us, yet no one could 

 maintain that its direction and the places where the grains fell were 

 predestined in the history of the earth. In other words : That which 

 we call chance plays a part also in the evolution of organisms, and the 

 assumption of a Power of Development, predestinating even in detail, 

 is contradicted by the fact that species are transformed in accordance 

 with the chance conditions of their life. 



This can be clearly demonstrated in the case of flowers. That 

 the wild pansy {Viola tricolor), which lives in the plains and on 

 mountains of moderate elevation, is fertilized by bees, and the nearly 

 allied Viola calcarata of the High Alps by Lepidoptera, is readily 

 intelligible, since bees are very abundant in the lower region, and 

 make the fertilization of the species a certainty, while this is not so 

 in the High Alps. There the Lepidoptera are greatly in the majority, 

 as every one knows who has traversed the flower-decked meads of 

 the High Alps in July, and has seen the hundreds and thousands 



