76 AN A ceo UNT OF BRITISH FLIES. 



hairs; abdomen dark brown, with thin, flesh-coloured incisions and 

 white hair. Posterior half of seventh ring, and the rest of the 

 abdomen, flesh coloured ; ^ genitalia black ; $ yellow. Wings 

 large, gray, with thick biackish-gray hairs, third longitudinal vein 

 bending in an almost straight angle to the posterior edge ; 

 I to \\ lin. 



' D. tritici, Kirby.— " The Wheat Midge." 



This is a very interesting species, on account of its being so in- 

 jurious to wheat, etc., and therefore we deal at greater length with 

 this than with most species. 



The eggs are transparent, cylindrical, rounded at both ends, four 

 times as long as broad ; they are laid in little heaps of six to thirty in 

 the inner bloom of the wheat, close to the embryo grain. 



The larvce. hatch in eight or ten days, first transparent, then yellow, 

 changing to orange. Composed" of 14 joints, the last cut out and 

 curved, with four little teeth. When it wishes to push itself forward, 

 it first curves itself round and holds on to some firm support. It 

 feeds on the germs and flowers of the wheat, and seems to possess 

 the power of jumping to the ground, where it buries itself from one 

 to five inches deep for about fourteen days, after which it changes to 

 a pupa. Before burying itself, the larva sheds its skin and appears 

 covered with fine-pointed hairs. 



Pupa. — Reddish-yellow, and apparently enclosed in a filmy trans- 

 parent case. Two bristles on the forehead. 



Imago. — Citron yellow, with downy hairs ; antenna blackish ; eyes 

 black ; legs pale yellow ; wings covered with strong hairs ; antenna 

 of $ f length of body, 13-jointed, hairy; those of $ \\ times 

 length of body, 25-jointed; thorax of ? gray; abdomen has brown 

 edges ; ovipositor can be extended to twice the length of the body, 

 and is as thin a* a hair ; wings of $ twice as long as abdomen. 

 Length of ? 1-5 to i-6 mm. ; of $ 0-9 to i mm. — 



The " Wheat Midge " comes out in June and July, and has been 

 seen in England as late as the 17th August. The ? seems to fly 

 about amongst the wheat stalks during the day, to begin laying eggs 

 an hour or two before darkness begins, and to continue laying 

 throughout the night. These " Midges " are also found in grass 

 along hedge sides and in clover.* 



There are probably two broods or more in one season. It attacks 

 wheat and rye, and according to Wagner, barley and oats also. Some 

 think that on first emerging it lays eggs on couch grass, and perhaps 



* Manual of Inj. Insects, p. 90. — E. A. Ormerod. 



