Everyone recognizes the destructive work of the Codling Moth, but everone does not know how to fight it. Much has been written about it, for the great loss occasioned by this one insect has compelled not only fruit-growers but also governments to investigate its habits and to determine practicable methods for its control. As a result of the labours of many scientific observers, its life-history is now fairly well known, and its control is now no longer a matter or mere chance.