The Glow- Worm and Other Beetles 



will be richly gifted. The larva has not the 

 least trace of organs of vision. What would 

 it do with sight, in the murky thickness of 

 a tree-trunk? Hearing is likewise absent. 

 In the never-troubled silence of the oak's in- 

 most heart, the sense of hearing would be a 

 non-sense. Where sounds are lacking, of 

 what use is the faculty of discerning them? 

 Should there be any doubts, I will reply to 

 them with the following experiment. Split 

 lengthwise, the grub's abode leaves a half- 

 tunnel wherein I can watch the occupant's 

 doings. When left alone, it now gnaws the 

 front of its gallery, now rests, fixed by its 

 ambulacra to the two sides of the channel. 

 I avail myself of these moments of quiet to 

 enquire into its power of perceiving sounds. 

 The banging of hard bodies, the ring of 

 metallic objects, the grating of a file upon a 

 saw are tried in vain. The animal remains 

 impassive. Not a wince, not a move of the 

 skin ; no sign of awakened attention. I suc- 

 ceed no better when I scratch the wood close 

 by with a hard point, to imitate the sound of 

 some neighbouring larva gnawing the inter- 

 vening thickness. The indifference to my 

 noisy tricks could be no greater in a lifeless 

 object. The animal is deaf. 

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