NATURAL HISTORY STUDIES 



a transformation-chamber. This is three or four 

 inches long, and is padded, Fabre tells us, " with a 

 fine swan's down, a delicate precaution taken by 

 the rough worm on behalf of the tender pupa." 

 The next step is to fall asleep and dream of becoming 

 a beetle. " The grub lays aside its tools, moults its 

 cuticle and becomes a pupa, lying, weakness personi- 

 fied, on a soft couch. The head is always turned 

 towards the door." This seems a little detail, but 

 the strength of a chain is that of its weakest link. 

 The supple grub can turn this way or that in its 

 chamber, but the coming beetle will not be able, to 

 turn or bend. " He must absolutely find the door 

 in front of him, lest he perish in the casket. Should 

 the grub forget this little formality, should it lie 

 down to its nymphal sleep with its head at the back 

 of the cell, the Capricorn is infallibly lost ; his 

 cradle becomes a hopeless dungeon." But the grub 

 forgets as little as it learns ! 



A third wonder of instinctive activities, which the 

 observations of Henri Fabre illustrate very well, 

 is that they are very apt to go wrong if there is any- 

 thing the least unusual in the circumstances. Often 

 subtle and perfect, without a loose thread from 

 first to last, the instinctive routine may end in 

 an almost ridiculous failure, when a grain of intelli- 

 ence would have saved the situation. 



Fabre once made a closed circuit of procession 

 caterpillars on the rim of a palm-vase in his garden, 

 and round this on a silken trail the creatures con- 

 tinued crawling and crawling for seven times 

 twenty -four hours, working round and round three 



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