HABITATIONS OF INSECTS. 455 



one of the larger nerves of the leaf is so strong as to re- 

 sist her efforts, she weakens it by gnawing it here and 

 there half through. What engineer could act more sa- 

 gaciously ? To form one of the conical or horn-shaped 

 rolls, which are not composed of a whole leaf, but of a 

 long triangular portion cut out of the edge, some other 

 manoeuvres are requisite. Placing herself upon the leaf, 

 the caterpillar cuts out with her jaws the piece which is 

 to compose her roll. She does not however entirely de- 

 tach it : it would then want a base. She detaches that 

 part only which is to form the contour of the horn. This 

 portion is a triangular strap, which she rolls as she cuts. 

 When the body of the horn is finished, as it is intended 

 to be fixed upon the leaf in nearly an upright position, 

 it is necessary to elevate it. To effect this, she proceeds 

 as we should with an inclined obelisk. She attaches 

 threads or little cables towards the point of the pyramid, 

 and raises it by the weight of her body a . 



A still greater degree of dexterity is manifested in 

 fabricating the habitations of the larvne of some other 

 moths which feed on the leaves of the rose-tree, apple, 

 elm, and oak, on the under-side of which they may in 

 summer be often found. These form an oblong cavity 

 in the interior of a leaf by eating the parenchyma be- 

 tween the two membranes composing its upper and under 

 side, which, after having detached them from the sur- 

 rounding portion, it joins with silk so artfully that the 

 seams are scarcely discoverable even with a lens, so as to 

 compose a case or horn, cylindrical in the middle, its 

 anterior orifice circular, its posterior triangular. Were 

 this dwelling cylindrical in every part, the form of the 

 3 Bonnet, ix. 188, 



