134 THE PESTS OF THE FARM. 



England. There, too, they sometimes take wing in immense swarms, 

 and, being probably aided by the wind, are not stopped in their 

 course either by mountains or rivers. On their first appearance in 

 Pennsylvania they were seen to pass the Delaware like a cloud. 

 Being attracted by light, they have been known, during the wheat 

 harvest, to enter houses in the evening in such numbers as seriously 

 to annoy the inhabitants. 



The old discussion, concerning the place where the Hessian fly 

 lays her eggs, has lately been revived by Miss Margaretta H. Morris, 

 of Germantown, Pennsylvania. Miss Morris believes she has es- 

 tablished that the ovum (egg) of this destructive insect is deposited 

 in the seed of the wheat, and not in the stalk or culm. She has 

 watched the progress of the animal since June, 1836, and has sat- 

 isfied herself that she has frequently seen the larva within the seed. 

 She has also detected the larva, at various stages of its progress, 

 from the seed to between the body of the stalk and the sheath of 

 the leaves. According to her observations, the recently hatched 

 larva penetrates to the centre of the straw, where it may be found 

 of a pale greenish white semitransparent appearance, in form some- 

 what resembling a silk worm. From one to six of these have been 

 found at various heights from the seed to the third joint. From 

 the foregoing, we are led to infer, that the egg, being sowed with 

 the grain, is hatched in the ground, and that the maggot afterwards 

 mounts from the seed through the middle of the stem, and, having 

 reached a proper height, escapes from the hollow of the straw to 

 the outside, where it takes the pupa or flax seed state. The fact 

 that the Hessian fly does ordinarily lay her eggs on the young 

 leaves of wheat, barley, and rye, both in the spring and in the au- 

 tumn, is too well authenticated to admit of any doubt. If, there- 

 fore, the observations of Miss Morris are found to be equally cor- 

 rect, they will serve to show, still more than the foregoing history, 

 how variable and extraordinary is the economy of this insect, and 

 how great are the resources wherewith it is provided for the con- 

 tinuation of its kind. 



Various means have been recommended for preventing or less 

 ening 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 universally adopted ; and it appears 

 doubtful whether any of them will ever entirely exterminate the 

 insect. Miss Morris advises obtaining " fresh seed from localities in 

 which the fly has not made its appearance," and that " by this 



