154 



Elementary Principles of Agriculture 



the larva feeds and grows and turns into a chrysalis, 

 or pupa, and out of this comes the mature insect again. 

 Take the common May-beetle, or June-bug as an ex- 

 ample. (Fig. 94.) The adult lays the egg among grass 

 roots in the early spring. From this then hatches a 

 small larva (white grub, or "grub- worm"), which feeds 

 on the roots in the soil. It grows rapidly, and, at the 

 end of the second season, goes into a dormant state and 

 changes into a pupa, and, at the end of two years, emerges 

 from the ground as a May-beetle, or June-bug. In the 

 larval stage, the June-bug often does much damage to 

 the roots of grasses, corn, wheat and garden plants, 

 while the adult feeds on the leaves of trees often fruit 

 trees. 



The caterpillar stage in insect development is quite 

 unlike the mature butterfly stage, and only the closest 

 watching of the life history of the "wiggle-tail" convinces 



Fig. 95. Plum curculio. 1, larva inside of peach; 2, mature insect depositing 

 egg. After Quaintance, United States Department of Agriculture. 



