Kay Robinson's Theory 



" I think there is no doubt whatever that all 

 the parts of a flower are modified leaves. The 

 original type of flowering plant I think we may 

 safely assume had a single stem and produced 

 its seed at the summit, as the crown of its year's 

 endeavour. The flower, before it became what 

 we would recognise as a flower, was a cluster of 

 protecting leaves round the seed-making parts of 

 the plant. To the production of the seed the 

 whole energies of the plant were devoted, and 

 into the cluster of leaves at the top of the stem 

 all the essences of the plant were concentrated. 

 If during the coming spring you handle and 

 examine the leaves at the end of the strong 

 shoots of thorns or fruit bushes, you will find that 

 the surface of the young leaves is quite sticky If 

 you observe browsing animals also, you will dis- 

 cover that contrary to expectation they do not 

 like strong-growing, juicy shoots, evidently pre- 

 ferring mature leaves lower down the branch. 

 This shows, I think, that plants have the power 

 of protecting their new shoots by crowding into 

 them the volatile oils and essences which they 

 produce as a protection against animals. Now 

 nectar appears always to be distasteful to grazing 

 and browsing animals ; and they also dislike 

 scented flowers. I think, therefore, that it is 

 reasonable to suppose that the nectar and scents 

 which now distinguish so many flowers were first 

 produced as an exudation of concentrated sap 



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