Larvae and their Work 



clothes-moth caterpillar from material of one colour to 

 that of another during his growth, he will end up with a 

 home rivalling Joseph's coat ; for with each reconstruction 

 he will insert material of another colour to those already 

 used. 



Certain insects make cases of leaves living leaves and 

 not snippets cut from a leaf. By one of Nature's in- 

 explicable vagaries, very small insects nearly always build 

 their cases of very large leaves and the means they adopt 

 to overcome their difficulties are ingenious in the extreme. 

 Of these " leaf-rollers," as they are called, one of the most 

 interesting is the birch weevil. The female of this little 

 beetle is too small to deal with a whole birch leaf, but she 

 is nothing daunted by that. Selecting a point on the leaf 

 margin nearly midway between leaf stalk and tip, she cuts 

 a way from margin to midrib and repeats the operation on 

 the opposite side, so that the leaf is cut in two, except for 

 the midrib, which is left undamaged. 



The next proceeding consists in rolling inwards the 

 edges of the leaf nearest to the tip till they form a tube 

 and the whole structure has the appearance of a small leaf 

 whose tip is elongated and formed into the shape of 

 a cylinder. The labours of the beetle, however, are not 

 yet completed. The leafy home is destined to form a 

 shelter for eggs and larvae and, in its present state, would 

 permit its living contents to fall out at the end. The 

 beetle, therefore, by the aid of legs and head, tucks in the 

 tip of the leaf to form an end to its cylinder, much as 

 a grocer tucks in the paper of the cones in which he sells 

 his sugar. 



A weevil, no larger than the birch weevil, constructs its 

 larval shelter of the poplar leaves on which it dwells. 

 This little beetle, though industrious, patient and, for its 

 size, strong, is yet far too weak to deal with the relatively 

 large leaf of the poplar-tree : a leaf which is far less pli- 

 able than the birch leaf. The ingenuity displayed by this 

 beetle to overcome its difficulty is little short of marvellous. 



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