74 FABRE'S BOOK OF INSECTS 



As soon as he is threatened with the rains of autumn he 

 begins to work upon his outer case. It is very rough at first. 

 Straws of uneven length and bits of dry leaves are fastened, 

 with no attempt at order, behind the neck of the sack or 

 undergarment, which must remain flexible so as to allow the 

 Caterpillar to bend freely in every direction. These untidy 

 first logs of the outer case will not interfere with the final 

 regularity of the building : they will be pushed back and 

 driven out as the sack grows longer in front. 



After a time the pieces are longer and more carefully 

 chosen, and are all laid on lengthwise. The placing of a 

 straw is done with surprising speed and skill. The Cater- 

 pillar turns it round and round between his legs, and then, 

 gripping it in his mandibles, removes a few morsels from one 

 end, and immediately fixes them to the end of the sack. He 

 probably does this in order that the silk may obtain a firmer 

 hold, as a plumber gives a touch of the file to a point that is 

 to be soldered. 



Then, by sheer strength of jaw, he lifts and brandishes his 

 straw in the air before laying it on his back. At once the 

 spinneret sets to work and fixes it in place. Without any 

 groping about or correcting, the thing is done. By the time 

 the cold weather arrives the warm case is complete. 



But the silky felt of the interior is never thick enough to 

 please the Caterpillar. When spring comes he spends all 

 his spare time in improving his quilt, in making it ever thicker 

 and softer. Even if I take off his outer case he refuses to 

 rebuild it : he persists in adding new layers to the lining, 

 even when there is nothing to be lined. The sack is lamentably 

 flabby ; it sags and rumples. He has no protection nor 

 shelter. No matter. The hour for carpentry has passed. 

 The hour has come for upholstering ; and he upholsters 

 obstinately, padding a house or lining a garment that no 

 longer exists. He will perish miserably, cut up by the Ants, 

 as the result of his too-rigid instinct. 



