Ontario Sessional Papers, 1898-99, . ears to be the most important of all insect importations,viz the introduction of foreign, carnivorous insects, whose office in their native country isto prey upon and destroy those that are destructive, which last we have unintentionallyimported into this country on trees, plants and shrubs, or in the fruits and grains comingto us from these same countries. That is to sxy, when we find that we have introduced adestructive species of insect, we are to go to the native habitat of this and there secure itsnative insect enemies, and introduce these to
Ontario Sessional Papers, 1898-99, . ears to be the most important of all insect importations,viz the introduction of foreign, carnivorous insects, whose office in their native country isto prey upon and destroy those that are destructive, which last we have unintentionallyimported into this country on trees, plants and shrubs, or in the fruits and grains comingto us from these same countries. That is to sxy, when we find that we have introduced adestructive species of insect, we are to go to the native habitat of this and there secure itsnative insect enemies, and introduce these to hold the former in check, as they do athome. Parasitism is natures insecticide—one of the forces that is employed by nature torestore equilibrium, so to speak, among natural organisms in point of numerical observing entomologist may every year witness proof of this, for he will observe somespecies to increase very rapidly during a short time, and, knowing of their fecundity, will 32 62Victoria. Sessional Papers (No. 23 A. 18^9. often be led to predict a serious outbreak. But at the opportune moment, Presto ! achange ! and the species that was but yesterday, as it were, literally swarming, is now re-duced to a minimum, while the dead are everywhere thickly scattered about. Twoinstances of this sort have, the present year, come under my own observation. Early inMay, the females of the grain aphis, Siphonophora avence, appeared on the growing wheatand were soon surrounded by their young. These insects were in a short time as plenti-ful as they usually are, at that season, in years of excessive abundance, and there seemed?every indication of an outbreak of the pest. But now there appeared a little Braconidparasite, Aphidius avenaphis, and within ten days there were few living adults to befound, though the distended, brown bodies of those that had succumbed to their minuteenemy were everywhere plentiful. It was as if a Mighty hand had been stretched forthaccompanied b
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Keywords: ., bookauthorontariol, bookcentury1900, bookdecade1900, bookyear1906
