The Processionary : the Moth 



the leader's. There is only one head, so to 

 speak; the procession may be compared with 

 the chain of segments of an enormous worm. 



Finally some spot is recognized as propi- 

 tious. The leading caterpillar halts, pushes 

 with his head, digs with his mandibles. The 

 others, still in a continuous line, arrive one by 

 one and likewise come to a halt. Then the 

 file breaks up into a swarming heap, in which 

 each of the caterpillars resumes his liberty. 

 All their backs are joggling pell-mell ; all their 

 heads are plunged into the dust; all their feet 

 are raking, all their mandibles excavating the 

 soil The worm has chopped itself into a 

 gang of independent workers. 



An excavation is formed in which, little by 

 little, the caterpillars bury themselves. For 

 some time to come, the undermined soil cracks 

 and rises and covers itself with little mole- 

 hills; then all is still. The caterpillars have' 

 descended to a depth of three inches. This 

 is as far as the roughness of the soil permits 

 them to go. In looser soil, the excavation 

 would attain a much greater depth. The 

 greenhouse shelf, supplied with fine sand, has 

 provided me with cocoons placed at a depth 

 of from eight to twelve inches. I would not 

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