178 ORDER DIPTERA. 



The worms acquire their full size and perfection, cast their skins, and descend to the 

 ground early in August, or perhaps as late as the middle of the month. Tliey bury them- 

 selves in the soil at the depth of about an inch, where they remain through the winter. 

 There is therefore but one brood in a season. The worm is speedily changed into a pupa, 

 in which state it remains until ready to issue from the ground in June or July of the next 

 year, in the imago state, or the perfect fly. 



The means that have been proposed to destroy this kind of wheat-fly are numerous : if 

 any of them are to be effectual, it is evident they should be resorted to over the whole 

 district infested by the insect. 



Among the remedies which seem to have been at least partially successful, is that of the 

 abandonment of the cultivation of winter wheat for the substitution of the spring variety, 

 and late sowing. The remedy operates on the principle of starvation, and would probably 

 be completely successful, were it not that grasses and other grains, as oats, rye and barley, 

 offer suitable recipients for the eggs of the insect, and furnish nutriment for its progeny. 



It is recommended to smoke them out. To carry on this plan of warfare, the flies must 

 be attacked in the evening, when they rise from their lurking places in the depths of the 

 grain. Brimstone, mingled with other combustible matter, should be burned in a position 

 to give them the full benefit of the smoke and vapor when they rise upon the wing, and 

 hover over the grain. 



Another recommendation is to sow fine quicklime over the field when the heads of the 

 grain are moist : this may be repeated several times. 



It is recommended by Dr. Fitch to first catch, and then kill them. The method of doing 

 this is sufficiently simple and easy, and deserves a trial. Take a long rope, attached to a 

 wide open tight bag ; and let two men, one at each end of the rope, pass through the field, 

 dragging the open wide-mouthed net over the heads of wheat. Go over the whole field in 

 this way, and millions of the fly will be caught if the net or bag is properly managed. ^ 



Deep ploughing is also a remedy that deserves trial, and indeed has been tried and 

 followed with success. This, of course, is to be resorted to after harvest : the object^^is to 

 bury the insects so deep that they will be unable to find their way out of the ground the 

 next season. 



The Cecidomyia which has appeared in this country is now regarded as identical with 

 the C. tritici of Europe, which has been known in England and Scotland for two-thirds of 

 a century, and was described at an early period. In this country, especially in the vicinity 

 of Albany and in the county of Berkshire in Massachusetts, it has been disappearing gra- 

 dually for the last ten years, and the wheat crop has again become a profitable one ; and 

 the probability is, that with our present knowledge of its habits, and of the means for its 

 extirpation or for avoiding its worst injuries, we may hereafter escape its depredations. 



