. Economic entomology for the farmer and the fruit grower, and for use as a text-book in agricultural schools and colleges; . Woolly apple-louse, Schizoneura lanigera: show- ing a group of specimens on bark, a crevice on a branch, in which they congregate, and a winged form. " woolly plant-lice," belonging to the genus Schizoncura. These cover themselves with a secretion resembling fine cottony fibre, which conceals them more or less completely. Thus there may appear to be tufts of cot ., , ton attached to leaves or twigs, beneath each of which we find, how- ever, a great mass of pla


. Economic entomology for the farmer and the fruit grower, and for use as a text-book in agricultural schools and colleges; . Woolly apple-louse, Schizoneura lanigera: show- ing a group of specimens on bark, a crevice on a branch, in which they congregate, and a winged form. " woolly plant-lice," belonging to the genus Schizoncura. These cover themselves with a secretion resembling fine cottony fibre, which conceals them more or less completely. Thus there may appear to be tufts of cot ., , ton attached to leaves or twigs, beneath each of which we find, how- ever, a great mass of plant lice busily en gaged in feeding. The '' alder - blig'ht'' and '' beech-blight'' are due to species of this kind, and more important than all is the '' apple- blight," or " the woolly apple-louse.'' This spe- cies, Schizoncura la7ii- gera, has been intro- duced into other countries, and is known in England and Aus- tralia as the "American ; Young trees are frequently injured by these aphids, which gather in masses on the trunks, and cause the death of the bark below the point of attack. The eggs may be found singly in the bark ^'^- 98- crevices during win- ter, completely envel- oped in the dry skin of the female, and from them appear, in spring, agamic, wing- less forms, which bear living young. This method of reproduc- tion continues until the winged type, which spreads to other localities, is produced in late summer. The sexed forms are wingless and mouthless, the female producing only a single Q^g ; but in the southern parts of our country it


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Keywords: ., bookcentury1900, bookdecade1900, booksubjectentomology, bookyear1