22 
This is of especial value in the North, where spring wheat is grown, 
and where the brood developed on the volunteer wheat may be the 
principal means of carrying the insect through the winter. 
Growth of resistant wheats.—As indicated in the paragraph, ‘‘ Effect 
on wheat,” the importance of. selecting varieties which are less injured 
by the attacks of the fly will be at once apparent. Such wheats are 
those having coarse, strong stems, and varieties which ‘‘ tiller” freely | 
or develop numerous secondary shoots. Among such wheats are the 
Underhill, Mediterranean, Red Cap, Red May, Clawson, ete. No 
wheats are, however, absolutely ‘‘ fly proof.” 
THE WHEAT MIDGE. 
( Diplosis tritict Kirby.) 
The wheat midge (fig. 10) is another dipterous enemy of wheat, allied 
to the Hessian fly and the wheat bulb-worm by belonging to the same 
order of insects, but is entirely distinct in appearance and habit. It 
Fic. 10.—Wheat midge (Diplosis tritici): a, female fly; b, male fly; ¢c, larva, ventral view—all enlarged 
(original). 

is believed to be identical with the notorious wheat midge of England 
and the Continent of Kurope, and might easily have been brought to 
this country, as was probably the case, with straw, as was the Hessian 
fly, or in soil from infested districts. (ae ding to Fitch, it was prob- 
ably first introduced into the Province of Quebec and passed down 
through the New England States into New York, and has thence spread 
westward throughout the Mississippi Valley. The adult insect isa very 
minute genat or midge, not exceeding one-tenth of an inch in length, 
and varying in color from orange to yellow, but tarnished or slightly 
smoky-tinged on the back above the wings. 
Injury by larve.—The injury occasioned by this insect to wheat iad 
allied grains is by its orange-yellow larve or maggots to the forming 
embryos in the wheat heads. The milky juice is extracted by these 
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