INSECT LIFE 185 



of curious interest and beauty. But how was Valezina 

 born, and how does she survive lean butterfly years ? 



The case of the wren's nest is one I have often 

 touched on. Many wrens' nests do assimilate to a 

 fine shade, to a nicety in material, with their sur- 

 roundings ; but to what extent (if any) the matching 

 of nest and site is essential to the well-being of wrens, 

 whether or not it is the result of the law in Nature 

 that cherishes the fittest, this is another matter. We 

 need be shown that it is essential to the welfare of 

 wrens that their nests should exactly match the matter 

 that surrounds them, before we can feel sure that the 

 wren's nest illustrates the working of the law. It is 

 the same, I think, with the painted lady, a swift and 

 wary butterfly that flies along many English roads and 

 fields in late summer. In September, a few years ago, 

 we had many in the wood. Now the painted lady 

 is a suddenly disappearing butterfly. She settles on 

 the road or path, shuts her pale orange-red and black 

 mottled wings, and turns to an invisible painted lady. 

 A friend told me that during a walk on the downs, a 

 summer or two since, he had seen butterflies, which 

 from his description I knew must be painted ladies, 

 disappear thus. The instant the painted lady is settled 

 on the ground and has shut her wings she is often 

 quite obscure ; one moment a gay, swift, alert butter- 

 fly the next nothing. 



She becomes invisible save to the trained and 

 knowing eye not because her markings on the under 



