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fly throw but little light upon its history in Minnesota, at least 
in that portion where only spring wheat is grown. And it was 
in those parts of the state that the maggots were so com- 
mon last summer, having been found from the Red River Valley 
to the central part of eastern Minnesota. They were also com- 
mon on the Experiment Farm. According to the accounts 
given by the above named entomologists, the flies found in the 
wheat fields in September and October deposit their eggs upon 
the young plants of winter wheat; the young maggots make 
their way downwards, feeding upon the central part of the 
stem near the surface of the ground, and cutting this off entirely, 
cause it todie. In these positions the maggots hibernate, ap- 
pearing again as adultsin spring. These flies of the first brood 
again deposit eggs, the maggots of which in time destroy the 
stems just above the upper joints. After killing this upper part 
of the plants, another brood of flies, the second generation, ap- 
pears, which emerge in July and depositeggs in volunteer wheat 
orgrass. From these maggots a third brood is produced, which 
develop into flies the same autumn, and deposit eggs upon the 
young plants of winter wheat. How many broods of this insect 
may be produced in Minnesota is not known. Only one thing 
is certain and that is that their life-history must be quite 
different in a region where volunteer wheat is a very uncom- 
mon thing, and where winter wheat is never grown. It is true 
we have in such regions a number of grasses that might 
possibly give this insect a shelter, as it is known to attack else- 
where, besides wheat, such grasses as wild-rye, blue-stem, 
Poa and even green pigeon grass. Perhaps this may be the 
case, though none of the wheat-stem maggots have thus far 
been found here in such grasses. Here at the Experiment 
Station the flies issued from material kept in breeding cages 
from July 22 till Aug. 4. 
The illustration shows three straws of wheat infested by the 
maggot. It shows also the pupa resting inside an open stem, 
and the injury caused by the maggot. A fly, natural size, is 
resting upon one of the straws. Larva, pupa and adult, greatly 
enlarged, are also shown. From many of the stems, instead of 
flies, parasites issued, showing that notwithstanding the hidden 
life led by these maggots, their enemies can find them. This 
