. Insect pests of farm, garden and orchard . one insidethe other, and the stage of growth of the larva may be readilydetermined by the number of cast skins held on the fork. Fromtlie likeness of this burden to a jDack, the larvte are often knownas ^ i^eddlers. In order to more firndy bind the excrement andcast skins to the fork, the larva? fasten them together by a finenetwork of silken threads, which are attached to the spines at thesides of the body. When fully grown the larva fastens itself to aleaf, its skin splits open along the back, and from it comes thepupa, which is held to the leaf b
. Insect pests of farm, garden and orchard . one insidethe other, and the stage of growth of the larva may be readilydetermined by the number of cast skins held on the fork. Fromtlie likeness of this burden to a jDack, the larvte are often knownas ^ i^eddlers. In order to more firndy bind the excrement andcast skins to the fork, the larva? fasten them together by a finenetwork of silken threads, which are attached to the spines at thesides of the body. When fully grown the larva fastens itself to aleaf, its skin splits open along the back, and from it comes thepupa, which is held to the leaf by its caudal fork, which is securelyencased in the faci-fork of the larval skin. About a week laterthe adult l^eetle emerges, eats for a few days and then disappearsfrom the sweet-potato patch until the following spring, doubtlessfeeding on morning glory until it enters hibernation. The Two-Striped Sweet-potato Beetle * This is usually the most common of the tortoise beetles attack-ing sweet potatoes. Tlie beetle is pale or brownish-yellow,. Fig. 310.—^The two-striped sweet-potato beetle (Cassida hiviltata Say): 1,larvsc on leaf; 2, larva; 3, pupa; 4, beetle—all enlarged. (After Riley.) striped with black as shown in Fig. 310, and the larva is yellowish-white, with a longitudinal band along the back, on either side of* Cassida bivittata Say. Family Chrysomelidoe. 434 INSECT PESTS OF FARM, GARDEN AND ORCHARD which is a much Hghter band. This species differs from the othersin that the hirva does not use its fajci-fork for carrying excrement,but merely covers it with cast skins and holds it at an angle fromthe body, instead of close over the back. The Black-legged Tortoise-beetle * This species very closely resembles the following one, the gol-den tortoise-beetle, but it is not so brilliant, is larger, has blacklegs, and the three black spots on each wing-cover are larger andmore conspicuous. The larva is a bright straw-yellow, with twocrescent-shaped black marks just back of
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Keywords: ., bookcentury1900, bookdecade1910, bookpublishernewyo, bookyear1915
