98 WILD BIRDS 



and fall into a sun rapture. But this ecstasy is 

 instantly ended when another hairstreak flies within 

 a foot or so of the chosen leaf. Then the rapt one 

 is up and chasing its rival or fellow, and the two gay 

 butterflies will twirl round and round each other as 

 they pass quickly across the tree. 



Often the giddy twirl will be doubled and quad- 

 rupled, other rapt sun-worshippers being drawn off 

 their leaves to join in the fun. The twirl, I think, 

 is very often an act of courtship, as it is among the 

 silver-washed fritillaries at midday ; but probably 

 there is also a good deal of anger and fighting as 

 well as gallantry in the bouts and chases around the 

 oak trees in August. The flight of these small, 

 smart butterflies is quick, but it cannot avail against 

 a brisk breeze as can the purple emperor's, and the 

 hairstreaks keep chiefly to their perches and sleep 

 in high wind. 



THE BUTTERFLY OF PARADISE 



It is one of Nature's paradoxes to achieve utility 

 through ornament. There has been a school of 

 thought in Europe of late years inclined to discount 

 Darwin's sexual selection. I cannot understand this 

 reaction. There is doubtless a vast deal of beauty 

 in the natural world which is no more the sign or 

 result of sexual selection than is an English or 

 Italian gallery of works of art. I have often urged 

 this. Darwin acknowledged that there was beauty 

 of colour and form which was quite inessential to the 

 work of evolution. But I cannot understand how 



