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JOURNAL OF ECONOMIC ENTOMOLOGY 
[Vol. 16 
the normal fly emergence. On September 30th another small wave of 
flies appeared. The source of these individuals was not determined and 
oviposition was so light that less than 3% infestation resulted in wheat 
of volunteer status. Pupariation of the progeny of the first wave began 
October 18th and w r as completed October 28th, pupariation of the prog¬ 
eny of the second wave began November 6th and was completed 
November 17th. Thus ended the normal activity of the fly for the fall. 
. On the night of October 6th a heavy rainfall supplied all fields with 
excess moisture. An apparent ccmplete transformation of fly larvae 
was noted October 16th. Adults issued October 27th to 30th and ovi¬ 
position w T as heavy. Over half the progeny entered the winter as small 
larvae. Pupariation began near the middle of January and ceased in 
general March 1st though naked larvae were found occasionally to April 
1st. Pupaiiation was not completed as death rate ran high through 
March and ended the tragic struggle. From records madein December 
and February a 25% death rate was computed for this interval. After 
this time no definite figures were obtainable, due to the disintegration 
of infested wheat plants. Concrete data obtained February 23rd showed 
a 70% pupariation as a whole for the progeny in early sowed wheat. 
Closer analysis revealed a greater pupariation of not less than 75% for 
forms existing in growing plants with less than 50% pupariation in 
dead plants. In wdieat representing the general fall seeding a 45% 
pupariation existed, with dead plants revealing a range of 38 to 54 in 
percentage of pupariation. On April 4th dead plants which had been 
infested showed 26% without fly life. Reversion of larvae in the flax¬ 
seeds began March 31st and ended near April 12th. Pupariation occurred 
from April 16th to 29th and adults emerged April 22nd to May 8th 
Mr. W. H. Larrimer of the Bureau of Entomology, noted that a 
transformation of the Hessian fly did not occur in stubble in the central 
and northern areas of Indiana during October but that practically all 
of the larvae remained as “hang-overs” in the stubble. To what extent 
the killing frosts and low temperatures influenced the behavior of the fly 
remains questionable. A few irregular flies were recorded by other 
workers of the Bureau of Entomology at points in the wheat area east 
of the Mississippi River during the heavy emergence at Centralia, 
Illinois, but in numbers of no consequence. South of the Ohio River the 
activity of the fly merged into normalcy of the southern area. 
The economic aspect of so heavy delayed emergence is important. 
The droughty condition of August, September, and early October inter¬ 
fered greatly with fall preparation of wdieat land. Seed beds which 
