SELECTION 165 



enables the insects to collect a large quantity of 

 honey, or pollen, with the least amount of trouble. 

 And it is also evident that it is very advantageous to 

 a humble bee to have a number of flowers in which 

 the honey is so locked up that only she or her 

 friends can extract it ; and we may reasonably sup- 

 pose that insects, finding honey sweet, began un- 

 consciously to cultivate the plants. If a bee found 

 that certain blue flowers always had more honey in 

 them than yellow or white ones-, she would certainly 

 visit the blue flowers first. She would not know 

 why there was more honey in the blue flow y ers. She 

 would never think that it was due to the difficulty 

 other insects found in extracting it, but she would 

 always visit them and expect a feast. We may 

 readily suppose that each particular bee had her 

 favourite plants which grew in the neighbourhood, 

 and, as she would constantly visit them in preference 

 to others, it is easy to see how they might become 

 isolated. In this way humble bees have caused long 

 nectaries to grow and the lips of the snap-dragon to 

 shut ; while moths have caused some flowers to keep 

 closed all day and so reserve their honey ; and others, 

 to give out scent only at night. 



The great number and abundance of plants whose 

 inconspicuous gamopetalous flowers show that they 

 were formerly visited by insects, although now fer- 

 tilised by other means, is a sufficient proof that 

 they have suffered no harm by the cessation of insect 

 visits. They are the abandoned ones, thrown on one 

 side when a better class of goods offered ; but they 

 have not died out, nor even suffered any loss. Many 



