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122 opinions and observations of the distinguished Naturalist alluded to, is, that he applies the term honey-dew, not to the saccharine fluid that transudes through the leaves of certain trees, but exclusively to the excrementitious matter deposited on them by the aphides. Assuming, then, that there are two kinds of honey-dew, one only of which is spoken of by Curtis, the following appears to us to be the rationale of the matter. Honey-dew, in whatever mode obtained, is the saccharine juice or sap of vegetables, indispensable to their vitality. During extreme heats it exudes through the pores of the upper surface of the leaves. In this state it may be exhaled during the sultry heat of the day, and fall again in the form of condensed vapour in the night; while what is secreted near the time of sunset remains on the leaves till the following morning. And, further, this same vegetable juice is extracted by another process besides the perspiratory,—namely, by the sucker of the aphis inserted into the tender bark of the tree, or into the footstalks of the leaves, and conveyed through the insect's system, and finally discharged almost in its primitive purity, from the abdomen, in liquid jets, unless there are ants at hand. In that case, the precious juice is sucked in by the last-named insects, with an eagerness which strongly testifies their sense of its richness.