INTRODUCTION. 83 



are necessarily forced to cut and sew up ; but, even 

 in this operation, they show an ingenuity and con- 

 trivance worthy of admiration/' 



A numerous tribe of small caterpillars feed, like 

 those just described, on the pulp of leaves, but form 

 no tent, contenting themselves with the protection 

 afforded by the walls of their galleries. These have 

 been named leaf-miners, and are very common on a 

 variety of plants. Their tracks appear on the surface 

 of the leaf like white tortuous lines, sometimes ex- 

 panding into areas, and often intersecting each other. 

 They are mostly very diminutive, as may be inferred 

 from the nature of their haunts, many of them finding 

 ample scope and accommodation within the dimen- 

 sions of a leaf "not equal in thickness to this paper. 



The most cursory observer cannot fail to have 

 noticed that the leaves of trees and shrubs are often 

 rolled together into hollow cylinders, folded in a 

 variety of forms or collected into packets, and that 

 they are held in these positions by a series of silken 

 ligaments. Each of these will be found to contain 

 a small caterpillar, generally belonging to the tribe 

 of insects now under consideration, which has 

 adopted this method of sheltering itself from the 

 weather, and feeding at its ease in concealment 

 from its numerous enemies. Leaves of great strength 

 and elasticity are frequently seen twisted and con- 

 voluted for this purpose, and it is not a little 

 surprising that creatures of such small dimensions, 

 frequently not exceeding two or three lines in length, 

 should be able to overcome the resistance of thg 



