. Bulletin of the Department of Agriculture. Agriculture; Agriculture. THE BEAX LADYBIRD. 19 chiefly on the upper surface, cutting irregular holes in and through the leaves, while the larvse feed on the lower surface and skeletonize the leaves, seldom cutting through them. The adult is a robust beetle, about one-fourth inch in length, of oval outline, pale brown, with each wing-cover marked with eight small black spots. The larva is light yellow and armed with branched spines. The yellow eggs are deposited from about the middle of June until August on the lower surface of the leaves, in c
. Bulletin of the Department of Agriculture. Agriculture; Agriculture. THE BEAX LADYBIRD. 19 chiefly on the upper surface, cutting irregular holes in and through the leaves, while the larvse feed on the lower surface and skeletonize the leaves, seldom cutting through them. The adult is a robust beetle, about one-fourth inch in length, of oval outline, pale brown, with each wing-cover marked with eight small black spots. The larva is light yellow and armed with branched spines. The yellow eggs are deposited from about the middle of June until August on the lower surface of the leaves, in clusters of 40 or more, and sometimes to the number of 1,500 by a single female. The larvae feed at first in colonies, but with larger growth scatter and become more or less solitary. The life cycle may be passed in summer in from 22 to 30 days; the eggs hatch in from 4 to 9 days; the larval period is between 15 and 21 days; and the pupal period varies from 3 to G days. In colder weather, however, these periods are longer. Two genera- tions or " broods " are produced annually. Cold weather in late autumn has the effect of destroying the in- sects, and their eggs are also destroyed by three species of pre- dacious ladybirds. In the control of the bean ladybird preventive measures are the most efficient, consisting of hand picking and brushing from the plants, clean culture, and early and late planting. Arsenicals possess some killing properties, but in the main act as repellents. Spraying with arsenate of lead. 1 or 2 pounds (powder), and with arsenite of zinc, 1 to 1| pounds (dry), to 50 gallons of water, are the most prom- ising. Bordeaux mixture, 4-4-50 formula, should be used alone and in combination with these arsenicals. Additional tests must be made with these substances to ascertain the most effective and economical combination that may be applied to the bean plants without scorching or burning the leaves. For the treatment of large areas infested by the bean la
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