bending which the insect was disposed to give it. If 

 we narrowly examine these two ribbands, their effect 

 will be visible. The second .will appear very tight, and 

 the first very slack ; the reason is because the latter 

 lias no greater degree of action, nor indeed ought to 

 have. You now comprehend that the roll is gradually 

 formed by the repetition of the same operations on dif- 

 ferent parts of the leaf. But it often happens that the 

 coarser edges resist too much ; the insect knows how to 

 weaken them by gnawing them here and there. In er- 

 der to form a cone, some more performances are neces- 

 sary. The roller cuts with her teeth, on the leaf, the 

 part that is to compose it. She does not detach it alto- 

 gether from it ; it would then want a base; she only 

 separates that part which is necessary to form the fold- 

 ings of the cone. The part is properly a slip, which she 

 rolls as she cuts it. She^ raises the cone on the leaf, 

 almost hi the same manner as we erect an inclined 

 obelisk. She fixes threads or little cables near the 

 point of the pyramid; she pre'sses on *hem with the 

 weight of her body, and thus forces the point to raise 

 itself. You may form an idea of the rest ; the me- 

 chanism is the same as that employed in making a roll. 

 Tiiese cells, in which the caterpillar lives, serve like- 

 wise as a retreat for the chrysalis. This latter would 

 not probably be sufficiently well accommodated with a 

 bare covering of leaf. The caterpillar lines the cell with 

 silk tapestry. Other species spin a cone for themselves 

 in it. 



7. Some leaves of plants are scarcely thicker than 

 paper. Would any one imagine there were insects skilful 

 enough to provide a lodging in such thin leaves as these, 

 so as to shelter themselves from the injuries of the wea- 

 ther? A leaf is to them a vast country, wherein they 

 make roads for themselves that are more or less wind- 

 ing ; they mine in the substance of the leaf, as our 

 miners do in the earth. From hence also they have 

 taken the name of miners of haves. They are ex- 

 tremely common : some belong to the class of cater- 



