176 DESTRUCTIVE INSECTS. 



children in this work by prizes, or by paying a certain amount 

 for the collection of unhatched egg-rings at any time between 

 August ist and the following April ; this is especially appli- 

 cable in villages where shade trees are infested 



Where orchards are thoroughly sprayed with poisons for 

 other pests, the tent-caterpillars are usually destroyed at the 

 same time. 



The caterpillars of the forest species quickly drop from the 

 tree when it is suddenly jarred, thus offering a very prac- 

 ticable method of collecting and killing them in orchards, and 

 especially on village shade trees. When the apple-tree tent- 



FIG. 240. FIG. 241. 



caterpillars and their nests or " signboards" are small, a whole 

 family can be quickly wiped out and destroyed with an old 

 mitten or rag in one's hand. These nests should be looked 

 upon as signboards of shiftlessness, for not many injurious 

 insects can be so easily controlled. 



Yellow-necked Apple-tree Caterpillar (Datana minis tr a). The 

 larva of this moth, which usually appears in July or August, 

 when full grown, is from an inch and a half to two inches 

 long. A family of them is so voracious that if undisturbed 

 they will soon defoliate a small tree. Though they spin no 

 web, they have a peculiar habit of collecting together in 

 masses in the noticeable position shown in Fig. 240. At such 

 times they may easily be destroyed by burning, or by brush- 

 ing them off on to the ground and killing them. The perfect 

 insect is shown in Fig. 241. 



The Apple Maggot (Trypeta pomonella') Fig. 242, lives in 

 the pulp of the apple and tunnels it in winding channels, ruin- 



