The Life of the Caterpillar 



er end. Its method of manufacture, by 

 means of a waistband whose fore-edge in- 

 creases in dimensions in proportion as the 

 rear-edge is pushed farther back, proves this 

 sufficiently. The hinder end becomes pointed 

 simply owing to the shrinking of the material, 

 which contracts of itself at the part where the 

 caterpillar's decreasing diameter no longer 

 distends it. There is thus at the point a per- 

 manent hole whose lips remain closed. The 

 caterpillar has only to go a little way back 

 and the stuff expands, the hole widens, the 

 road is open and the excretions fall to the 

 ground. On the other hand, so soon as the 

 caterpillar takes a step forward into his case, 

 the rubbish-shoot closes of itself. It is a very 

 simple and very ingenious mechanism, as good 

 as anything contrived by our seamstresses to 

 cope with the shortcomings of a boy's first 

 pair of breeches. 



Meanwhile the grub grows and its tunic 

 continues to fit it, is neither too large nor too 

 small, but just the right size. How is this 

 done? If the text-books were to be credited, 

 I might expect to see the caterpillar split his 

 sheath lengthwise when it became too tight 

 and afterwards enlarge it by means of a piece 



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