The Hessian fly*, the most important insect pest affecting the wheat crop in Iowa, was imported from Europe probably either just before or during the period of the Revolutionary War. Its depredations were first observed on Long Island, New York, in 1779, in the vicinity of Lord Howe's old encampment site of three years before. As the Hessian mercenaries, who constituted a part of the foregoing army, were much despised in America and as it was generally supposed that the pest had been brought into this country in straw used for the bedding of these soldiers, the common and obnoxious name, "Hessian fly", was bestowed upon this insect. The fly spread rapidly westward and it is now established thruout the wheat growing belt of the United· States. It would be difficult to estimate the total damage done by this pest since its importation into America, but tax amounting to at least $100,000,000 in a single year has been charged against it.