66 LEAF-MINING INSECTS 



verted into a spacious chamber. Mines so made are called 

 tentiform mines. They usually occur on the lower side of 



Fig. 26. Leaf of the Western Sycamore, Platanus occidentalis, with three 

 mines of the moth, Lithocolletis felinella as found in December. Beyond 

 each mine is a blotch of green in the brown leaf, giving a variegated appear- 

 ance to the whole tree. 



Fig. 27. Diagram of one of the mines shown in figure 3. c, cocoon 

 containing pupa; m, midden-screen of silk;/, frass. 



the leaf of the host plant, that is, the cuticle is first loosened 

 on the lower side. 



