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convinced ere this day:—so earnest and candid an enquirer after 
truth, and one so capable of giving to every fact its due weight, 
cannot long remain in error, upon a point so susceptible of de- 
monstration as this. 
Its Parasites. 
It is well known that one of the most effectual means for keep- 
ing the Hessian fly in check and preventing it from literally swarm- 
ing all over our land, has been provided by nature herself. Other 
insects have been created, apparently for the very purpose of 
preying upon this, and thus preventing it from becoming inordi- 
nately multiplied. The world is indebted to Mr. Herrick for much 
interesting information respecting these insects, the result of his 
own accurate and patient investigations. As we purpose, should 
we succeed in more fully tracing out the history of these and oth- 
er Cecidomyian parasites, making them the subject of a separate 
memoir at some future day, we refrain from devoting to them any 
considerable space in the present paper. The general reader, 
however, will scarcely pardon us, if we omit all allusion to them. 
We therefore subjoin a brief sketch of the contents of this part 
of Mr. Herrick’s article. 
The Hessian fly is preyed upon and devoured by at least four 
other insects. When its eggs are laid upon the wheat leaves, they 
are visited by an exceedingly minute four winged fly, (a species 
of Platygaster,) which punctures the egg and deposites in it four 
or six eggs of its own: the Hessian fly worm hatches, grows, and 
passes into its flax seed state with these internal foes feeding upon . 
it: it now dies, and its destroyers in due time escape from the flax 
seed shell. Three other minute four winged flies, or bees as they 
would be called in common language, destroy the fly when in its 
flax seed state. The most common of these, by far, is Say’s Ce- 
raphron destructor. Alighting upon the wheat stalks, instinct in- 
forms them precisely where one of these flax seeds lies concealed. 
They thereupon “sting” through the sheath of stalk, and into the 
body of the worm, placing an egg therein, which hatching to a 
maggot, lives upon and devours the worm. Such are the means 
which nature has provided for preventing this pest from becoming 
