THE CECIDOMYIA CULMICOLA. 
583 
cends the straw on the outside, where it attaches itself 
firmly, and awaits its change ; the outer skin becomes the 
puparium. In the pupa or flax-seed state, it closely resem- 
bles the C. destructor. Should the culm of the wheat be- 
come prematurely hard before the worm has finished feeding, 
as is often the case, the insect will remain imprisoned for 
life, passing through its changes inside the straw, and there 
perish without the power to escape, unless some accidental 
passage be made for it. I have liberated,” she adds, “ hun- 
dreds with my penknife, and thousands make their escape 
after the grain has been reaped and carried into the barn. 
When the insect is thus unnaturally retarded, the time of 
its perfect development is uncertain ” ; and she has “ found 
them on the straw, and in spiders’ webs, from June until 
September.” 
Four of the specimens sent to me by Miss Morris were 
males. Another subsequently received was a female. The 
former were not more than half the size of the latter, and 
indeed were smaller even than the wheat-fly, which they 
seem somewhat to resemble. The female was evidently 
much darker-colored originally than the males. These in- 
sects were genuine specimens of Cecidomyia, and apparently 
of a different species from the Hessian fly. The condition 
of the specimens, which had suffered by compression and 
by being badly preserved, was such, that an accurate com- 
parison and description of them could not be made. I under- 
stand that the species has disappeared from Germantown 
and the vicinity, and hence no opportunity for obtaining 
living or recent specimens has occurred since the year 1843. 
Various means have been recommended for preventing 
or lessening the ravages of the Hessian fly ; but they have 
hitherto failed, either because they have not been adapted 
to the end in view, or because they have not been univer- 
sally adopted ; and it appears doubtful whether any of them 
will ever entirely exterminate the insect. It is stated in 
the before mentioned Report of the Philosophical Soci- 
