Prevention.

The sole practical means of prevention is to cultivate the wheat stubble, or "gratten," as it is called in Kent, directly the corn is carried, where the crop has been affected, so as to bury the larvæ deep in the ground. A dressing of hot lime might be applied with good results, but in this case the land should be very lightly scarified with one of Coleman's lightest scarifiers in order to bring the lime into close contact with the larvae. After some days the land should be deeply ploughed to bury them and effectually prevent further transformation, at least to the imago form. Couch grass must be eradicated and hedge-sides and out-sides of fields carefully brushed. It should be remarked here that brushing hedge-sides and all outsides, grassy roads, waste corners, and headlands should be done systematically, twice if possible, once early, before grasses seed and insects hatch out, and again in the autumn when insects are hibernating upon grasses and hedge-side and outside rubbish, either as perfect insects or in the egg stage. And it is of not much use merely to brash, the rubbish should be burnt or carried away to be mixened.

As a proportion of the larvæ in some seasons remain in the ears and are taken to the ricks and barns it is most important that the chaff, after the corn is thrashed and cleaned, which is not wanted for the horses, should be burnt or put in a mixen or under cattle in yards. The "cavings" and rubbish from barn-floors, rick staddles, and where the thrashing machine has stood should be similarly treated. "Cavings" and chaff should not be suffered to lie about in rick-yards and corners of fields, or at least not after March.

In Philadelphia, Maine, Massachusetts, and other American States, after a bad attack of Cecidomyia, the fanners give up putting in winter wheat and sow spring wheat, which does not come into ear until after the flies have ceased to a great extent from troubling. But this would not answer in this country, as late sown spring wheat and wheat coming late into ear are not satisfactory, and spring wheat sown at the right time is not much later in flowering than winter sown wheat. In Canada the farmers make large fires round corn fields to stifle the flies or to drive them from the neighbourhood.