WHEAT 



19 



The Hessian fly. The adult insect is a small, almost black, 

 two-winged fly, resembling the mosquito, and of about the 

 same size. As a rule the flies remain close to the ground, 

 and in the fall, when they are most abundant, they may be 



FIG. 3. LIFE HISTORY OF THE HESSIAN FLY 



seen depositing their little pink eggs in the grooves of the 

 upper surface of the leaves. The eggs hatch into the larvae, 

 which change from a pinkish to a greenish-white tinge when 

 full grown. The larva goes into the pupa or "flaxseed" 

 stage, a period of resting in which the larva is encased in a 



