160 INSECT ARCHITECTURE. 



cell may not appear very difficult; — nor would it 

 be so if the caterpillars had fingers, or any parts i 

 which were equivalent to those delicate and admirable 

 natural instruments with which man accomplishes his 

 most elaborate works. And yet the human fingers 

 could not roll a rocket-case of paper more regularly 

 than the caterpillar rolls his house of leaves. A leaf 

 is not a very easy substance to roll. In some trees 

 't is very brittle. It has also a natural elasticity,— 

 a disposition to spring back if it be bent, — which is 

 caused by the continuity of its threads, or ncrvures. 

 This elasticity is speedily overcome by the ingenuity 

 with which the caterpillar works ; and the leaf is 

 thus retained in its artificial position for many weeks, 

 under every variety of temperature. We will examine, 

 in detail, how these little leaf-rollers accomplish their 

 task. 



One of the most common as well as the most 

 simple fabrics constructed by caterpillars, may be dis- 

 covered during summer on almost every kind of 

 bush and tree. We shall take as examples those 

 which are found on the lilac, and on the oak. 



A small but very pretty chocolate-coloured moth, 



£ i 



Lilac-tree Moth. (Lawfrrnia Ribeana, Stephen«?) 



abundant in every garden, but not readily seen from 

 its frequently alighting on the ground which is so 

 nearly of its own colour, deposits its eggs on thu 

 leaves of the lilac, and of some other trees, appro- 

 priating a leaf to each egg. As soon as the cater- 

 pillar is hatched, it begins to secure itself from birds 

 and predatory insects by rolling up the lilac leaf into 



