136 INDIKECT INJURIES CAUSED BY INSECTS. 



stated concerning tlie latter insect, and tlie additional facts 

 which I shall now adduce, will amply show. 



The ravages of the animal just alluded to, which was first 

 noticed in 1776, and received its name from an erroneous idea 

 that it was carried by the Hessian troops in their straw from 

 Germany, were at one time so universal as to threaten, where 

 it appeared, the total abolition of the culture of wheat ; though 

 the injury which it now occasions is much less than at first. 

 It commences its depredations in autumn, as soon as the plant 

 begins to appear above ground, when it devours the leaf and 

 stem with equal voracity until stopped by the frost. When 

 the return of spring brings a milder temperature the fly ap- 

 pears again, and deposits its eggs in the heart of the main 

 stems, which it perforates, and so weakens, that when the ear 

 begins to grow heavy, and is about to go into the milky state, 

 they break down and perish. All the crops, as far as it ex-^ 

 tended its flight, fell before this ravager. It first showed 

 itself in Long Island, from whence it proceeded inland at 

 about the rate of fifteen or twenty miles annually, and by the 

 year 1789 had reached 200 miles from its original station. I 

 must observe, however, that some accounts state its progress 

 at first to have been very slow, at the rate only of seven miles 

 per annum, and the damage inconsiderable; and that the 

 wheat crops were not materially injured by it before the year 

 1788. Though these insect hordes traverse such a tract of 

 country in the course of the year, their flights are not more 

 than five or six feet at a time. Nothing intercepts them in 

 their destructive career, neither mountains nor the broadest 

 rivers. They were seen to cross the Delaware like a cloud. 

 The numbers of this fly were so great, that in wheat-harvest 

 the houses swarmed with them, to the extreme annoyance of 

 the inhabitants. They filled every plate or vessel that was 

 in use ; and five hundred were counted in a single glass 

 tumbler exposed to them a few minutes Avith a little beer 

 in it.i 



1 Encyelop(Bd. Britann. viii. 489 — 495. Though the ravages of the Hessian fly 

 in the United States have not been so extensive of late, much injury is still oc- 

 casionally suffered from it, as stated by Mr. Say, who described it under the 

 name of Cecidomyia destructor, and as I learn from E. C. Herrick, Esq. of New 

 Haven, Connecticut, who has taken great pains to ascertain the metamorphosis 



