LEAF-ROLLERS 187 



The Curculionid is cleverer than we at this sort of 

 business and does not share our opinion. What she 

 says to herself is : 



" On the ground, amid the obstruction of the grass, 

 my labours would be impracticable. I want elbow-room ; 

 I want the thing to hang in the air, where there are 

 no obstacles of any kind. And there is a more serious 

 consideration : my grub would refuse a rank, dried-up 

 sausage ; it msists on food that retains a certain fresh- 

 ness. The scroll which I intend for its consumption 

 must be not a dead leaf, but an impaired leaf, not 

 altogether deprived of the juices with which the tree 

 supplies it. I must wean my joint, but not kill it out- 

 right, so that the dying leaf may remain in its place for 

 the few days during which the extreme youth of the 

 worm lasts." 



The mother, therefore, having made her selection, takes 

 up her stand on the stalk of the leaf and there patiently 

 drives in her rostrum, turning it with a persistency that 

 denotes the great importance of this thrust of the bodkin. 

 A little wound opens, a fairly deep wound, which soon 

 becomes a point of mortification. 



It is done : the sap-conduits are cut and aUow only a 

 scanty proportion to ooze through to the edge. At the 

 injured point, the leaf gives way under the weight ; it 

 bends vertically, withers a little and soon acquires the 

 requisite flexibility. The moment has come to work it. 



That bodliin-thrust represents, although much less 

 scientifically, the prick of the hunting Hymenopteron's 

 sting. The latter wants for her offspring a prey now 

 dead, now paralyzed ; she knows, with the thorough- 

 ness of a consummate anatomist, at what pomts it 

 behoves her to insert the sting to obtain either sudden 



