The Life of the Caterpillar 



weather permitting, the caterpillars leave the 

 nest and go down the bare part of the 

 bough which forms the pole of the tent. The 

 road is broad, for this axis is sometimes 

 as wide as the neck of a claret-bottle. The 

 descent is accomplished without any attempt 

 at order and always slowly, so much so that 

 the first caterpillars to come out have not yet 

 dispersed before they are caught up by the 

 others. The branch is thus covered by a con- 

 tinuous bark of caterpillars, made up of the 

 whole community, which gradually divides 

 into squads arid disperses to this side and that 

 on the nearest branches to crop their leaves. 

 Now not one of the caterpillars moves a step 

 without working his spinneret. Therefore the 

 broad downward path, which on the way 

 back will be the ascending path, is covered, 

 as the result .of constant traffic, with a multi- 

 tude of threads forming an unbroken sheath. 

 It is obvious that this sheath, in which each 

 caterpillar, passing backwards and forwards 

 on his nocturnal rambles, leaves a double 

 thread, is not an indicator laid down with the 

 sole object of simplifying the journey back to 

 the nest : a mere ribbon would be enough for 

 that. Its use might well be to strengthen the 

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