The Glow-Worm and Other Beetles 



employed by the Buprestes and the Longi- 

 corns. 



The larva does not prepare the path of 

 deliverance; it is left for the perfect insect to 

 open itself a passage through the wood. 

 What I have before my eyes tells me more 

 or less plainly the sequence of events. The 

 larva, whose presence is proved by galleries 

 blocked with packed sawdust, do not leave 

 the centre of the trunk, a quieter retreat, less 

 subject to the vicissitudes of the climate. 

 Metamorphosis is effected at the junction of 

 the straight gallery and the curved passage 

 which is not yet made. When strength 

 comes, the perfect insect tunnels ahead for a 

 distance of more than four inches and opens 

 up the exit-passage, which I find choked, not 

 with compact sawdust, but with loose pow- 

 dery rubbish. The dead insects which I 

 strip of their mycelium-shrouds are weaklings 

 whose strength deserted them mid-way. 

 The rest of the passage is lacking because 

 the labourer died on the road. 



With this fact of the insect itself boring 

 the exit passage, the problem assumes a more 

 troublesome form. If the larva, rich in lei- 

 sure and satisfied with its sojourn in the in- 

 terior of the trunk, simplifies the coming 

 emergence by shortening the road, what must 

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