THE APPLE LEAF-MINER 45 
light as a glistening spot. The eggs hatch in about six days, 
and the young caterpillars, without exposing themselves to 
the outside world, immediately enter the leaf. At first they 
make a narrow channel, but with the increase in size of the in- 
sect and its appetite the channel becomes wider, and a trum- 
pet-shaped mine, as previously described, is the result, 
The caterpillars moult, or change their coat, five times. 
These coats are alike in color and structure, but vary in size 
to accommodate the growing insects. As the old clothes are 
shed they are judiciously pushed out through a small opening 
in the lower surface of the mine. The insects further display | 
their cleanly habits, unlike many other leaf-miners, by deposit- 
ing their excrement without the mine through this same open- 
ing. 
The caterpillars reach their full growth about the middle 
of July, when they transform to pupae. This resting stage 
. lasts only from eight to ten days. At the expiration of this 

Fic. 9—A badly infested tree. The upper branches have lost their 
foliage, and the fruit is not fully developed. 
