8 THE COLOURS OF FLOWERS. 



part out of which they were originally evolved. For 

 example, if we ought to regard them as altered and 

 modified leaves, then we may fairly conclude that the 

 earliest petals were green ; while, if we ought to 

 regard them as altered and modified stamens, then 

 we may fairly conclude that they were yellow. 

 Which of these two alternatives is the most likely 

 to be true ? Apparently, the latter. 



Petals are in all probability originally enlarged and 

 flattened stamens, which have been set apart for the 

 special work of attracting insects. It seems likely 

 that all flowers at first consisted of the central organs 

 alone— that is to say, of a pistil, which contains the 

 ovary with its embryo seeds ; and of a few stamens, 

 which produce the pollen, whose co-operation is 

 necessary in order to fertilise these same embryo 

 ovules and to make the pistil mature into the ripe fruit. 

 But in those plants which took to fertilisation by 

 means of insects — or, one ought rather to say, in 

 those plants which insects took to visiting for the 

 sake of their honey or pollen, and so unconsciously 

 fertilising — the flowers soon began to produce an 

 outer row of barren and specialised stamens, adapted 

 by their size and colour for attracting the fertilising 

 insects ; and these barren and specialised stamens 

 are what we commonly call petals. Any flowers 

 which thus presented brilliant masses of colour to 

 allure the eyes of the beetles, the bees, and the 

 butterflies, would naturally receive the greatest 

 number of visits from their insect friends, and would 

 therefore stand the best chance of setting their seeds, 

 as well as of producing healthy and vigorous offspring 

 as the result of a proper cross. In this way, as we 



