SECRETARY'S REPORT. 15 



D, in first range, firmly holds from his own experience, that the 

 fly, though often abundant, rarely injures the crop unless rust, mil- 

 dew, or some unfavorable atmospheric influence retards the growth 

 of the plant, thus giving the maggot time to commit his ravages, as 

 otherwise, the plant being perfectly healthy and thrifty, the grain 

 fills plumply and is abundant, be the maggots never so plenty.* 



* As one proof of this, Mr. Haines stated that on threshing his grain, he had 

 fouud maggots in great abundance, and his crop very slightly, if at all, lessened 

 thereby. Whether his opinion as above given, be correct or not, he probably in 

 this instance mistook the maggot of the " wheat mow fly" for that of the ordinary 

 ■wheat midge or fly, the maggot of which usually leaves the plant at an earlier 

 period before harvesting. Of the "wheat mow fly," only recently known as a 

 depredator upon the wheat crop, Mr. Fitch, in his treatise on insects, says : " Sev- 

 eral years ago, a farmer in my neighborhood, soon after gathering his wheat into 

 the liarn, found countless myriads of small worms were crawling out of it, literally 

 covering the mow of grain, and wandering away from it, to every part of the ba^n. 

 These worms it is evident, had just now completed their growth, and were crawling 

 about in search of the moist earth wherein to bury themselves, to repose during 

 their pupa state. It would seem that some cause had made them later than usual 

 in reaching maturity; and had the wheat remained in the field, a few days longer, 

 they would have escaped from it there, so generally that no notice of them would 

 have been taken, and the fact would never have been known that such an army of 

 insects had had their subsistance upon this crop. 



Alarmed with the numbers of these worms, and fearing they would perhaps wholly 

 destroy the mow of grain, the proprietor had the whole of it threshed immediately. 

 I happened to visit the barn as the threshed grain was being winnowed, when the 

 above facts were communicated to me. The heap of uncleaned grain was literally 

 alive with these worms and the cracks in the floor were filled with them. The 

 kernels of wheat appeared to be shrunk in the same manner as when they have beea 

 infested with the wheat midge. I put a number of these worms into a small box 

 ■with some of the chafl"and grain. Other engagements diverted my attention from 

 this subject, and it was wholly forgotten, until many months afterwards, when, 

 happening to open the box, I found in it quite a number of small flies, which had 

 completed their transformations, and perished in their confinement. It therefore 

 appears, that it is by no means essential to these worms to bury themselves in the 

 moist earth, though that is doubtless their natural habit. But if they can find any 

 crevice in the dry barn where they can stow themselves and lie undisturbed, it is 

 all they require in order to complete their transformations. 



The worms, according to my recollection, were much like the little yellow maggots 

 of the wheat midge, but were of a dull white color and rather larger. Their trans- 

 formations are like those of flies generally, the outer skin of the larva or maggot 

 contracting and becoming dry and hard and forming the case, within which the 

 insect lies in its pupa state. It is but the tenth of an inch long and three hund- 

 reths in diameter; it is shining, and of a pale yellow color, of an oval or rather an 



