INDIRECT INJURIES CAUSED BY INSECTS. 127 



ed.^ That there was sufficient cause for apprehension, should it have so 

 turned out, what I have formerly stated concerning the later insect, and 

 the 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 cul- 

 ture 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 appears 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 extended 

 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 inter- 

 cepts them in their destructive career, neither mountains nor the broadest 

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

 bers 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 with a little beer 

 in it.^ 



America suffers also in its wheat and maize from the attack of an insect 

 of a different order ; which, for what reason I know not, is called the 

 chintz bug-fly. It appears to be apterous, and is said in scent and color 

 to resemble the bed-bug. They travel in immense columns from field to 

 field, like locusts, destroying every thing as they proceed ; but their in- 

 juries are confined to the states south of the 40th degree of north latitude.*^ 

 From this account the depredator here noticed should belong to the tribe 



» Linn. Trans, ii. 76—80. 



* Encyclopad. 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 occasionally 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 and economy of this insect; and either this or an 

 allied species described by M. Kollar, destroyed a large proportion of the wheat crops in 

 Hungary in 1833, and extended itself also to France. Dr. Hammerschmidt, who has also 

 given an account of this insect, has called it Cecidomyia tritici, supposing it to be the same 

 with the insect described by Mr. Marsham and Mr. Kirby ; but as the mischief done by 

 the larva of the former is caused by its eating into the stem and weakening the whole plant, 

 while the latter is injurious by destroying the pollen of the blossom, the two insects are 

 evidently very distinct, as indeed their diflferent color proves. — Kollar on Ins. injurious to 

 Gardeners, &c. 118. 



3 Young's Annals of Agriculture, li. 471. 



