The Poplar-Weevil 
in a sense paralysed, which can be easily 
fashioned into a cylinder; she is perfectly 
familiar with the little leaf-stalk, the petiole, 
in which the vessels that disperse the energy 
of the foliage are gathered in a tiny bundle; 
and she inserts her drill here, here only and 
never elsewhere. Thus at one blow, without 
much trouble, she effects the ruin of the 
aqueduct. Where can the long-nosed insect 
have learnt her clever trick of dralining 
springs? 
The leaf of the poplar is an irregular 
rhombus, a spear-head whose sides are 
expanded into pointed wings. The manu- 
facture of the cylinder begins with one of 
these two lateral corners, the right or the 
left indifferently. 
Despite the hanging posture of the leaf, 
which makes the upper or lower surface 
equally easy of access, the insect never fails 
to take up its position on the upper side. 
It has its reasons, dictated by the laws of 
mechanics. The upper surface, which is 
smooth and more flexible, has to form the 
inside of the cylinder; the under surface, 
which has greater elasticity because of its 
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