BRITISH BUTTERFLIES 



the Large Heath a trifle obscurer at rest on the bram- 

 ble leaf than it would be with the wing up. 



But I do not believe the real explanation or object 

 of this withdrawal of the " eye " from public view is 

 protection of the butterfly from enemies of prey by 

 inconspicuity, or by assimilation to surroundings 

 (gross words to use of a sylph like the Large Heath ! 

 but I know not how to avoid them here). My notion 

 is that there is no night enemy that need be cheated 

 if it could be cheated thus. Protection of butterfly 

 beauty against weather this, I think, is the meaning 

 of the withdrawn " eye." I admit that, if you set 

 out to look for butterflies at rest and matching their 

 environment, you will find them. The Small Skipper 

 butterfly sleeping on the spear-thistle looked greeny- 

 grey, I noticed, matching his perch. We watched a 

 Meadow Brown, disturbed by large raindrops, perch 

 on a birch twig, and put away his " eye," and we agreed 

 he would pass for a dead leaf. But other Small Skip- 

 pers, small and large kinds, slept on seeding grass 

 heads and the matching was not close ; and, after all, 

 is a Meadow Brown so very like a dead birch leaf when 

 you come to think of it ? 



More striking was the case of the Golden Y moth, 

 the pretty insect which is out in moist places in the 

 birch wood, and flies often by day. I watched one 

 settle on the trunk of a birch tree. It has some dark 



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