THE PINE PROCESSIONARY 131 



becility. Facts, however, forced me to accept the in- 

 credible. Let us describe them in detail. 



The circular procession begins, as I have said, on the 

 30th of January, about midday, in splendid weather. 

 The caterpillars march at an even pace, each touching 

 the stern of the one in front of him. The unbroken 

 chain eliminates the leader with his changes of direction; 

 and all follow mechanically, as faithful to their circle as 

 are the hands of a watch. The headless file has no 

 liberty left, no will ; it has become mere clockwork. And 

 this continues for hours and hours. My success goes 

 far beyond my wildest suspicions. I stand amazed at it, 

 or rather I am stupefied. 



Meanwhile, the multiplied circuits change the original 

 rail into a superb ribbon a twelfth of an inch broad. I 

 can easily see it glittering on the red ground of the pot. 

 The day is drawing to a close and no alteration has yet 

 taken place in the position of the trail. A striking proof 

 confirms this. 



The trajectory is not a plane curve, but one which, at 

 a certain point, deviates and goes down a little way to 

 the lower surface of the cornice, returning to the top 

 some eight inches farther. I marked these two points of 

 deviation in pencil on the vase at the outset. Well, all 

 that afternoon and, more conclusive still, on the follow- 

 ing days, right to the end of this mad dance, I see the 

 string of caterpillars dip under the ledge at the first point 

 and come to the top again at the second. Once the first 

 thread is laid, the road to be pursued is permanently 

 established. 



