THE FAERY YEAR 



the plantain or grass head ? Why does he sleep in 

 horizontal position ? I believe that he and other 

 butterflies and moths sleep aloft to avoid toads and 

 other creatures of prey lurking beneath. Hence 

 protection by position is far more important to them 

 than protection by " mimicry " that is by resembling 

 the spots on which they station themselves. Next 

 as to the small heath's horizontal sleeping attitude 

 by exposing himself broadside to the descending rain, 

 is he not taking up a bad position ? It seemed so to 

 me, till I examined small heaths in the steady down- 

 pour of rain, and found them dry and unhurt. The 

 fact is, this little butterfly has a waterproof perfectly 

 adapted to requirements. The raindrop falls on his 

 wings, but, bouncing or rolling off, leaves them quite 

 dry. Put this to the test by letting raindrops fall off 

 the spike of your umbrella on the small heath's wing ; 

 they do no harm. Now, if the butterfly slept hori- 

 zontally on the ground, or any hard and fixed place, 

 his wings would soon be drenched and battered to 

 ruin. 



The plantain bends before the storm, and with it 

 the butterfly. So the risk of being washed away or 

 injured is minimized. It is a most ingenious and 

 beautiful safeguard. The small heath, apparently 

 exposed to the full power of the storms of wind and 

 rain, remains on his plantain head cosy and dry. 

 After an hour's exposure to the same weather, in the 

 field where the butterfly sleeps, my mackintosh clings 

 heavy and sodden to the calves of the legs. The 

 small heath has the better waterproof. 



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