27 
From these puparia, October 18, three adults emerged—two males 
ind a female. These were confined, alive, in a small bottle, and 
he single female at once laid eggs freely on the sides of the 
mottle, but nowhere else. By the next morning after the appear- 
ince of these imagos, this single fly had perished after laying 
sixty-seven eggs. 
On the 16th November, this plot of August wheat contained an 
ibundance of naked larvae, with a few recent puparia. A handful 
)f wheat sent to the office contained one hundred and ninety-one 
mmature specimens,—fifty-eight being darkened puparia, thirty- 
me puparia freshly formed, and one hundred and two larvae of 
various sizes, from two millimeters up—the smallest seven aver¬ 
ting about two and a half millimeters in length. Search in the 
)ther wheat fields of this vicinity gave no evidence whatever of 
he occurrence of the fly. 
If we scan now more closely the results in these experimental 
dots, we shall note in the first place a much later appearance of 
he fly than the reports of my correspondents had given 
’eason to anticipate. While the letters quoted agree substantially 
hat full grown larvae and puparia appear in wheat from the last 
)f August to the middle of September, our own earliest examples 
vere obtained September 22 (Edgewood), at which time few or 
lone of the larvae were more than half grown; and the specimens 
sent from Billett Station on the 28th September were in about 
he same relative stage of advancement. 
' 
The late appearance at Edgewood might be reasonably attrib- 
ited to the failure of the-earlier sowings to germinate, no wheat 
ieing in condition to attract females in search of suitable places 
'or the deposition of their eggs until about August 15 or 20. As 
he time for the maturing of the brood is seen, however, to vary 
ittle from six weeks at that season of the year, it is likely that 
it Edgewood the eggs were laid about September 21. On the 
)ther hand, at Billett Station, where the rain-fall was much more 
imely and abundant, there was no such failure of the earlier sow- 
ngs; and we can only adjust the facts there observed to the 
heory of a normal earlier development of the midsummer flies by 
supposing that the overwhelming attack made upon the first two 
Dlots by the wheat bulb v r orm, prevented the female Hessian flies 
:rom resorting to' the same wheat. Evidently, however, another 
season’s experiments wfilLbe needed to explain these discrepancies. 
A furfher item of interest appears when w T e compare the coa¬ 
lition of the fields at Edgewood and Billett Station, October 12. 
kt the former place, about ninety-five per cent, of the larvae had 
formed the puparia, while at Billett Station no more than ten per 
rent. w r ere so far advanced, the remainder being naked larvae of 
ill sizes, from the smallest up. This discrepancy is, however, ex¬ 
plained wdthout difficulty by the different surroundings of the 
lelds. The one at Edgew^ood being the only tract in the entire 
region in which w 7 e were able to find before harvest any traces of 
he fly, it probably became infested only from the flies which de- 
