FABRE'S BOOK OF INSECTS 



eyes with which the fully-developed insect will be richly 

 gifted. The larva has not the least trace of any organs 

 of sight. What would it do with sight, in the murky 

 thickness of a tree-trunk? Hearing is likewise absent. 

 In the untroubled silence of the oak's inmost heart the 

 sense of hearing would be superfluous. Where sounds 

 are lacking, of what use is the faculty of discerning 

 them? 



To make the matter certain I carried out some ex- 

 periments. If split lengthwise the grub's abode becomes 

 a half-tunnel, in which I can watch the occupant's 

 doings. When left alone it alternately works for 

 a while, gnawing at its gallery, and rests for awhile, 

 fixed by its pads to the two sides of the tunnel. I took 

 advantage of these moments of rest to inquire into its 

 power of hearing. The banging of hard bodies, the ring 

 of metallic objects, the grating of a file upon a saw, were 

 tried in vain. The animal remained impassive: not a 

 wince, not a movement of the skin, no sign of awakened 

 attention. I succeeded no better when I scratched the 

 wood near it with a hard point, to imitate the sound of 

 some other grub at work in its neighbourhood. The in- 

 difference to my noisy tricks could be no greater in a 

 lifeless object. The animal is deaf. 



Can it smell? Everything tells us that it cannot. 

 Scent is of assistance in the search for food. But the 

 Capricorn-grub need not go in quest of eatables. It 



