HOW THE WOODPECKER CATCHES A GRUB 11 



by the click of the rails than by the noise that 

 comes on the air. Even our dull ears can de- 

 tect the woodworm, but we cannot locate him. 

 How, then, is the woodpecker to do what we 

 cannot do ? , 



Doubtless experience teaches him much, but 

 one observer suggests that the woodpecker places 

 the grub by the sense of touch. He says he 

 has seen the red-headed woodpecker drop his 

 wings till they trailed along the branch, as if 

 to determine where the vibrations in the wood 

 were strongest, and thus to decide where the 

 grub was boring. But no one else appears to 

 have noticed that woodpeckers are in the habit 

 of trailing their wings as they drill for grubs. 

 It would be a capital study for one to attempt 

 to discover whether the woodpecker locates his 

 grub by feeling, or whether he does it by hear- 

 ing alone. Only one should be sure he is look- 

 ing for grubs and not for beetles' eggs, nor for 

 ants, nor for caterpillars. By the energy with 

 which he drills, and the size of the hole left 

 after he has found his tidbit, one can decide 

 whether he was working for a borer. 



But when the borer has been located, he has 

 yet to be captured. There are many kinds of 

 borers. Some channel a groove just beneath the 

 bark and are easily taken ; but others tunnel 



