. Economic entomology for the farmer and the fruit grower, and for use as a text-book in agricultural schools and colleges; . Heart of a stag-beetle, showing the wings and chambers : at the side, the interior ot a chamber, to show the valves. Insects have no system of arteries and veins, and only one real blood-vessel, which serves also as the heart. This, as has been

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Keywords: ., bookcentury1900, bookdecade1900, booksubjectinsects, bookyear1906