CLASSIFICATION AND DESCRIPTION OF COMMON INSECTS 249 



drops to the ground, burrows beneath the surface and spins a 

 silken cocoon. 



Pupa. — Pupa within cocoon; duration one week. Hibernates. 



Control. — Frequent fumigation with tobacco to kill the adults. 



Grape Blossom Midge {Contarinia johnsoni Sling.). — A pest in the 

 Chatauqua grape belt of New York. 



Adult. — A midge ifg inch long, with yellowish body and straw 

 colored legs. End of May. 



^i,^^- — Minute, grey, elongate, curved; about 25 laid in each bud 

 which becomes swollen and yellowish and reddish when maggots 

 begin to feed. 



Fig. 157. — The wheat midge {Diplosis trilici): a, female fly; b, male fly; c, larva. 

 Enlarged. {After Marlale, U. S. Bur. Ent.) 



Larva. — Whitish to yellow-orange; }^2 inch long; passes the winter 

 in a small oval silk-lined earthen cocoon about 6 inches below surface 

 of ground. 



Pupa. — Formed at end of April. 



Control. — Spray with Black Leaf 40 just as buds of early varieties 

 begin to open, and again a week later. 



Wheat Midge {Diplosis = Contarinia, tritici Kirby). — A European 

 pest, destructive to wheat, introduced probably by way of the Province 

 of Quebec (Fig. 157). 



Adult. — A minute orange-yellow fly Hq inch long, smoky-tinged on 

 the back above the wings. June-August. 



