148 THE DARWINIAN THEORY 



which are the only insects visiting the common red 

 clover, there would soon be no clover. 



Large conspicuous flowers are visited much more 

 frequently and by many more kinds of insects than 

 are small inconspicuous ones. The long tubular 

 corolla of many flowers is acquired so that certain 

 insects alone should be able to get at the honey, 

 these insects being the ones best suited for fertilising 

 the flower. 



The bright colour of the whole flower is to attract 

 insects at a distance ; the coloured dots and lines on 

 the petals serve to guide it to the store of honey. 

 This fact was proved by Darwin, who cut off the 

 petals of Lobelia, and found that these flowers were 

 then neglected by bees, which were perpetually 

 visiting the other flowers. 



In the case of flowers which are fertilised by 

 means of the wind, such as grasses and trees, the 

 flowers are small and not gaily coloured, and possess 

 an enormous amount of pollen and a very large 

 stigma. Moreover, in localities where insects are 

 few in number, we find the flowers very insignificant 

 in colour : for example, in the Galapagos Islands, 

 which have only one butterfly and no bees. 



White flowers are fertilised by nocturnal insects, 

 chiefly moths. These flowers are always odorous, 

 the jasmine and clematis for example, and often 

 odorous only at night. Alpine flowers, again, are 

 peculiarly beautiful, and the size of individual flowers 

 is increased owing to the comparative scarcity of 

 insects in the places where they grow, and the 

 consequent necessity of attracting them from afar. 



