The dock false-worm an The dock false-worm : an apple pest dockfalsewormapp265newc Year: 1916 BX7LLETIX 265, U. S. DEPAETMEXT OE AGRICULTURE. DESCRIPTION. THE EGG. The egg of the dock false-worm is bean shaped or kidney shaped, and somewhat flattened, pearly white, and with a soft, pliable shell. It is protected by the tissues of the leaf in which it is deposited, (PI. I, fig. 1.) The average length is mm., and the width mm. About a day before hatching a dark spot shows through, which is one of the eyes of the larva, the head being seen from the side. Shortly before the larva breaks
The dock false-worm an The dock false-worm : an apple pest dockfalsewormapp265newc Year: 1916 BX7LLETIX 265, U. S. DEPAETMEXT OE AGRICULTURE. DESCRIPTION. THE EGG. The egg of the dock false-worm is bean shaped or kidney shaped, and somewhat flattened, pearly white, and with a soft, pliable shell. It is protected by the tissues of the leaf in which it is deposited, (PI. I, fig. 1.) The average length is mm., and the width mm. About a day before hatching a dark spot shows through, which is one of the eyes of the larva, the head being seen from the side. Shortly before the larva breaks through the shell the outline of the head is discernible. THE LARVA. The larva would not ordinarily be noticed on the plants until nearly full grown, and it appears at this time as a slender, hairless larva, with a finely wrinkled olive-green or blue-green skin and a scattering of conspicuous white tubercles. After passing the last- molt, which brings it to the stage in which it bores into pithy stems or apples, the larva changes in ap- pearance. (Fig. 2.) It is no longer velvety, but has rather a sleek, shiny appearance, though the wrin- kles still persist. Its color is a brighter greenâmore of an apple greenâand the larva seems almost Fig. 2.âThe dock false-worm: a, Full-grown larva, ° . . enlarged; I, seventh larval segment, much en- translucent, Since the alimentary larged; c, portion of cranium, highly magnified; enal j§ empty. The tubercles are d, actual length. (Original.) i ⢠i â *⢠no longer white and can not be dis- tinguished. If an infested stem or apple be cut open, the larva within will be found to have much the same appearance as before it entered, except that it has become shrunken and curved and has lost the power of locomotion. A detailed description of the various larval stages follows: First instar.âLength. mm. General color very light gray: food showing through green. Somewhat slug shaped, thoracic region slightly enlarged, body tape
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