CHINCH BUG WEST OF MISSISSIPPI RIVER. 



25 



hatching from these eggs constitute the spring generation (fig. 13 c, e,f,g) 

 and are the ones that do such enormous damage to wheat and young 

 Some of this generation reach maturity as they are migrating 



corn. 



from wheat to corn, but most of them reach the corn (see fig. 12) 

 before maturing and do much damage thereto. It is because 

 the immature bugs reach the young corn in such immense numbers 

 and mass upon the plants that they do such widespread damage 



Fig. 12. — Corn plant about 2 feet tall, infested by chinch bugs. (Original.) 



(see PI. IV), their depredations ceasing as they reach maturity. Only 

 on rare occasions is an entire cornfield devastated, and often the dep- 

 redation is brought to an abrupt standstill within a few rods of the 

 opposite margin of the field because the bugs have reached maturity 

 and dispersed. During July and August the insects mate, and the 

 eggs for the second generation are deposited about the corn plants, 

 where the young, on hatching, find an abundance of easily accessible 

 food. Some of this generation reach maturity (see fig. 14) before 

 the corn becomes dry, and migrate to volunteer wheat, but most of 



