CREATION BY LAW. 273 



produced as if a gardener destroyed the short ones 

 and sowed the seed of the long ones only ; and this 

 we know by experience would produce a regular in- 

 crease of length, since it is this very process which 

 has increased the size and changed the form of our 

 cultivated fruits and flowers. 



But this would lead in time to such an increased 

 length of the nectary that many of the moths could 

 only just reach the surface of the nectar, and only the 

 few with exceptionally long trunks be able to suck up a 

 considerable portion. 



This would cause many moths to neglect these flowers 

 because they could not get a satisfying supply of nec- 

 tar, and if these were the only moths in the country 

 the flowers would undoubtedly suifer, and the further 

 growth of the nectary be checked by exactly the same 

 process which had led to its increase. But there are 

 an immense variety of moths, of various lengths of 

 proboscis, and as the nectary became longer, other and 

 larger species would become the fertilizers, and would 

 carry on the process till the largest moths became 

 the sole agents. Now, if not before, the moth would 

 also be affected, for those with the longest probosces 

 would get most food, would be the strongest and most 

 vigorous, would visit and fertilize the greatest number 

 of flowers, and would leave the largest number of de- 

 scendants. The flowers most completely fertilized by 

 these moths being those which had the longest nec- 

 taries, there would in each generation be on the average 

 an increase in the length of the nectaries, and also 



T 



