. Economic entomology for the farmer and the fruit grower, and for use as a text-book in agricultural schools and colleges; . one part of emulsion in ten or twelve parts of water being ordi- narily sufficient. Whale-oil soap is quite as effective, and is preferable on some house or conservatory plants, while even the pyrethrum extract is useful on a small scale, and is, perhaps, the cleanest of all on house-plants.

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Keywords: ., bookcentury1900, bookdecade1900, booksubjectentomology, bookyear1