i$o THE EVOLUTIONIST AT LARGE. 



and though singed and blinded twice or 

 three times by the flame, must still wheel 

 and eddy into it, till at last they perish in 

 the scorching blaze. Their instincts, or, to 

 put it more clearly, their simple nervous 

 mechanism, though admirably adapted to 

 their natural circumstances, cannot be equally 

 adapted to such artificial objects as wax 

 candles. The butterfly in like manner is 

 attracted automatically by the colour of his 

 proper flowers, and settling upon them, sucks 

 up their honey instinctively. But feeding is 

 not now his only object in life : he has to 

 find and pair with a suitable mate. That, 

 indeed, is the great end of his winged exist- 

 ence. Here, again, his simple nervous sys- 

 tem stands him in good stead. The picture 

 of his kind is, as it were, imprinted on his 

 little brain, and he knows his own mates the 

 moment he sees them, just as intuitively as 

 he knows the flowers upon which he must 

 feed. Now we see the reason for the butter- 

 fly's large optic centres : they have to guide 



