. The book of the garden. Gardening. 114 CULINARY OR KITCHEN GARDEN. largest, with a single nervure curved at the centre, where there is an obscure black fascid, with a black spot at the extremity; inferior wings smaller, with a central longitudinal nerv- ure ; six legs, rather long, black, and powdered with white; feet long, and composed of two equal joints, terminated with two very fine curved claws, with a hook between them. These little creatures seem not only to withstand the cold, but even to multiply during the winter; for Eeaumur says he found them in every state . in December and Janu
. The book of the garden. Gardening. 114 CULINARY OR KITCHEN GARDEN. largest, with a single nervure curved at the centre, where there is an obscure black fascid, with a black spot at the extremity; inferior wings smaller, with a central longitudinal nerv- ure ; six legs, rather long, black, and powdered with white; feet long, and composed of two equal joints, terminated with two very fine curved claws, with a hook between them. These little creatures seem not only to withstand the cold, but even to multiply during the winter; for Eeaumur says he found them in every state . in December and January, as he had done in summer; and this wUl account for their extra- ordinary increase, which, from the small num- ber of eggs laid by each female, appears at first to be inexplicable. Moreover, in less than a month the insects undergo all their changes— from the deposition of the egg to the pairing of the perfect progeny ; it is therefore possible to have twelve generations in a, year. Reaumur calculated that a single female might, in the course of a year, give origin to 200,000 descen- ; The best mode of lessening their numbers is to gather the infected leaves during winter and spring and burn them. Any choice plant at- tacked by them might be fumigated with tobacco smoke; and, indeed, small crops might be covered with canvass, and undergo the same operation; but such and all other means hitherto tried would be impossible with crops upon a large scale, as the brassioaceous tribe in general are. In some seasons they are more destructive than in others, and would become a frightful scourge to man, were it not that they have their natural enemies in a species of Cynips, and one also of Acarus, which feed upon them. Anthomyia irassicce of Bouche (the cabbage- fly).—The larvse of this insect live underground, in the roots and stems of most of the Brassica tribe, eating passages through them, and causing them to rot. It is one of the most destructive of insects, and
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Keywords: ., bookcentury1800, bookdecade1850, booksubjectgardening, bookyear18
