. Injurious and useful insects; an introduction to the study of economic entomology. Insects; Beneficial insects; Insect pests. 64 INJURIOUS AND USEFUL INSECTS is shuffled off downwards, like a stocking stripped off the leg, the loose skin of the upper part of the body being passed through the girdle. In order to provide room enough for this, the spinning larva doubles up its body, throwing the head far back, so as to give it a wide sweep. When once the larval skin is cast, the pupa has only to lean back a little, in order to get a comfortable support from its girdle. The cabbage whites illust
. Injurious and useful insects; an introduction to the study of economic entomology. Insects; Beneficial insects; Insect pests. 64 INJURIOUS AND USEFUL INSECTS is shuffled off downwards, like a stocking stripped off the leg, the loose skin of the upper part of the body being passed through the girdle. In order to provide room enough for this, the spinning larva doubles up its body, throwing the head far back, so as to give it a wide sweep. When once the larval skin is cast, the pupa has only to lean back a little, in order to get a comfortable support from its girdle. The cabbage whites illustrate the points of difference. Fig. ^6.—Larva of large cabbage white. X 2. between a butterfly and a moth. In them, as in all butter- flies, the wings are broad, erected over the back when at rest, or fully expanded, but never folded fanwise, as often happens in moths. The fore and hind wings are never secured by a bristle and catch, as is the case with most moths. The body is slender. The feelers are long, and thickened or knobbed at the tip. Like other butterflies, the cabbage whites fly by day, and usually only in sunshine. The pupa is fixed by the tail, and, as in some other butterflies, is further secured by a silken girth. It is hard to find a simple and effec- tive remedy against Washes and sprays produce Fig. 47.—Larva of small cabbage white. X 2, the larvae of the cabbage whites. little effect, for the larvae conceal themselves on 'the under side of the leaves, or in the heart of the cabbage; and, besides, there is a waxy bloom on a cabbage-leaf, which throws off the liquid. It is possible, by patient search, to remove the egg-clusters of the large cabbage white, but the process is slow and troublesome; no one would dream of hunting for the single eggs of the other two species. A frequent change of crop will keep down the numbers of. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - colorati
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectinsects, bookyear1902
