56 



THE HESSIAN FLY. 



(Cecidomyia destructor Say. — Dipiera : Tipididce. 

 Bt the Rev. C. J. S. Bethune, M.A. 



For many years this Province has happily been almost entirely free from the ravages of 

 the Hessian Fly. During the present year (1877) however, this very destructive insect has 

 again appeared in the wheat-fields, and is attracting much attention from farmers and others 

 speciully interested in the culture of this most important cereal. A.s far as we have been 

 able to obtain information the Hessian fly has been recently observed in the counties of Grey, 

 Simcoe, York and Ontario, and also in the County of Oxford. No doubt, if not checked, it will 

 soon spread over a much wider area, and cause much loss and disappointment to our wheat- 

 growers. 



The subject being one of so great importance, it has been considered advisable to repro- 

 duce here our Report upon this insect, published six years ago {Report of the Entomological 

 Society of Ontario, 1871, pages 392-5). 



The Hessian fly, together with a number of other most destructive insects, has come to 

 us from the other side of the Atlantic. European entomologists have repeatedly maintained 

 that it must be a native of America, as no such in.sect was observed amongst their wheat- 

 fields during a long series of years ; and Mr. Curtis has even gone so far as to call it " the 

 American ynheaX-rmigs," in contradistinction to what he terms " the i?n7(sA wheat-midge " 

 (C. tritici). It is now, however, generally admitted that it is of European origin, and it is 

 almost certain that it was first brought to this continent in some straw used for the purpose 

 of packing by the Hessian troops, under Sir William Howe, during the American War of 

 Independence. These soldiers landed on Staten Island, and on the west end of Long Island, 

 in the year 1776, and in this neighbourhood the fly was first observed; hence it obtained 

 its popular name of " Hessian Fly." Having multiplied in these places — as Dr. Harris 

 relates — " the insects gradually spread over the southern part of New York and Connecti- 

 cut, and continued to proceed inland at the rate of fifteen or twenty miles a year. They 

 reached Saratoga (two hundred miles from their original station) in 1789." Proceeding in 

 this manner, the tiny pest gradually spread over the country, and has been found in almost 

 every locality where wheat is grown. In the old world also, its depredations have'been 

 sufiicieiitly great to attract notice in England, France, Germany, Austria, Switzerland, 

 Italy, Russia, — in fact in almost every country where this grain is cultivated to any extent. 

 Our own Dominion, though frightfully devastated in subsequent years, was not invaded 

 by the pest till about the year 1816, when it became prevalent in Lower Canada. It 

 appears to have been first noticed in this Province in the year 1846. (For a detailed his- 

 tory, of its progress in this country and the neighbouring States down to the year 1854, see 

 Prof. Hind's Essay, pp. 42-46.) 



So much has been said and written respecting the Hessian fly, and so many descrip- 

 tions of it have appeared in agrieultural and scientific publications, that we feel disinclined 

 to attempt any new account of it or repeat once more " an oft told tale." As we have no 

 new light to throw upon the subject, and, with the exception of some specimens received 

 from Ancaster during the past summer, have had no opportunity for some years of investi- 

 gating its habits, we shall not hesitate to make free use of the writings of others, especially 

 those which are not likely to be accessible to the majority of our readers. In every case 

 we shall, of course, make due acknowledgement of the source from which information is 

 derived. 



The Hessian fly, though known for its destructive qualities for sometime before, was 

 first scientifically described by Mr. Say — one of the most eminent of the early American 



