Kay Robinson’s Theory 
“T 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 
271 
