The Glow- Worm and Other Beetles 



lets with bits of leaves; that of the Cotton- 

 bees of making bags of wadding with the 

 flock gathered from certain plants. 

 Whether the pieces be cut from the leaves 

 of this shrub or that, or at need from the 

 petals of some flower; whether the cotton- 

 wool be collected here or there, as chance may- 

 direct the encounter, the industry undergoes 

 no essential changes. 



In the same manner, nothing changes in 

 the art of the Dung-beetle, victualling him- 

 self with materials in this mine or that. 

 Here in truth we have immutable instinct, 

 here we behold the rock which our theorists 

 are unable to shake. 



And why should it change, this instinct, 

 so logical in its workings? Where could it 

 find, even with chance assisting, a better 

 plan? In spite of an equipment which varies 

 in the different genera, it suggests to every 

 modelling Dung-beetle the spherical shape, 

 a fundamental structure which is hardly af- 

 fected when the egg is placed in position. 



From the outset, without the use of com- 

 passes, without any mechanical rolling, with- 

 out shifting the thing on its base, one and 

 all obtain the ball, the delicately executed 

 compact body supremely favourable to the 

 grub's well-being. To the shapeless lump, 

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