H4 THE BIOLOGY OF THE SEASONS 



flower " ; but further reflection lead him to see the signifi- 

 cance of Goethe's thesis, and he then wrote a famous passage, 

 which describes the nature of the flower in a beautiful way, 

 combining inaccuracy and insight in a manner absolutely 

 incomparable. " You will find," he said, " that, in fact, all 

 plants are composed of essentially two parts the leaf and 

 the root one loving the light, the other darkness ; one 

 liking to be clean, the other to be dirty ; one liking to grow 

 for the most part up, the other for the most part down ; and 

 each having faculties and purposes of its own. But the pure 

 one which loves the light has, above all things, the purpose of 

 being married to another leaf, and having child-leaves, and 

 children's children of leaves, to make the earth fair for ever. 

 And when the leaves marry they put on wedding-robes, and 

 are more glorious than Solomon in all his glory, and they 

 have feasts of honey, and we call them flowers." 



In the great majority of cases the pollen is carried from 

 one flower to another of the same kind by an insect intent 

 on its own affairs collecting nectar and pollen. As the 

 dusting with pollen secures not only fertilisation, but cross- 

 fertilisation, and as the latter is sometimes the only possible 

 mode, and sometimes, at least, the most advantageous mode 

 as far as the crop of seeds is concerned, we are not surprised 

 to find that flowers exhibit numerous adaptations which 

 attract insect-visitors of a profitable kind, and secure that the 

 visits are made the most of. 



Taking the simplest attraction first that of nectar- 

 production we have no difficulty in recognising its natural- 

 ness. The plant is a sugar-factory ; the leaves make enough 

 and to spare ; there is a surplus which oozes out as " a feast 

 of honey." But an unregulated overflow would be obviously 

 disadvantageous in attracting unwelcome guests, thus 

 nectaries become floral, and their position in the flower is 

 often finely strategic. When the fit and proper visitors have 



