BUTTERFLY PSYCHOLOGY. 149 



and till the warmth and sunlight have given 

 it strength. For the wings are by origin a 

 part of the breathing apparatus, and they 

 require to be plimmed by the air before the 

 insect can take to flight. Then, as it grows 

 more accustomed to its new life, the heredi- 

 tary impulse causes it to spread its vans 

 abroad, and it flies. Soon a flower catches 

 its eye, and the bright mass of colour attracts 

 it irresistibly, as the candle-light attracts the 

 eye of a child a few weeks old. It sets off 

 towards the patch of red or yellow, probably 

 not knowing beforehand that this is the 

 visible symbol of food for it, but merely 

 guided by the blind habit of its race, im- 

 printed with binding force in the very con- 

 stitution of its body. Thus the moths, which 

 fly by night and visit only white flowers 

 whose corollas still shine out in the twilight, 

 are so irresistibly led on by the external 

 stimulus of light from a candle falling upon 

 their eyes that they cannot choose but 

 move their wings rapidly in that direction ; 



