Half hours with insects . my, with the aid of the needleand lens. He can also turn to the lower forms, such as thewater fleas, rotifers, infusoria and rhizopods, with which thewaters teem winter and summer, and find, with a few dipsof tlie net, material for weeks of observation and study. 32 PACKARD.] THE POPULATION OF AN APPLE TEEE. IGl 7. The Jfopulatmn of an Tree* A FRENCH author has written a very pleasant littlebook entitled the Population of a Pear Tree. Ofthe population of an apple tree a ponderous tomecould be written, but in this essay on the insects injuringthis facile prince
Half hours with insects . my, with the aid of the needleand lens. He can also turn to the lower forms, such as thewater fleas, rotifers, infusoria and rhizopods, with which thewaters teem winter and summer, and find, with a few dipsof tlie net, material for weeks of observation and study. 32 PACKARD.] THE POPULATION OF AN APPLE TEEE. IGl 7. The Jfopulatmn of an Tree* A FRENCH author has written a very pleasant littlebook entitled the Population of a Pear Tree. Ofthe population of an apple tree a ponderous tomecould be written, but in this essay on the insects injuringthis facile princeps of our fruit trees, we shall confine our-selves mainly to the more injui-ious kinds, giving a brief andcondensed account of the most important species. Aboutseventy-five species in all are known to prey upon the appletree. We may first consider those kinds found PREYING UPON THE ROOTS. TJie Pear Blight, or Eriosoma ivjri (Fig. 127 ; a, the gall;6, larva ; c, female ; c?, leg ; e, beak ; /, antenna of female ; Fig. Blight Insect. <7, of larva; after Riley) sometimes causes a good deal ofdisturbance to the health of the tree, lessening the vigorof its growth and causing the leaves to turn of a paler andmore yellowish hue than usual. If there is no borer under11 1 162 HALF HOURS WITH ENSECTS. [Packard. the bark, nor any other apparent cause, and if it be a youngtree, it may be found on removing the soil from tlie rootsthat a number of gall-like excrescences, sometimes a coupleof inches in diameter, are attached to them. On openingthe galls a number of small wingless plant lice, with largerwinged ones, will be observed in the crevices. Their bodiesare covered with a woolly exudation, whence their commonname, woolly blight. Dr. Fitch, who has given us thebest account of this anno3dng blight insect, says that theparent insect at the end of autumn works her way downalong the side of the root, there depositing her stock ofeggs, and then, the grand aim of her life accomplish
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectinsects, bookyear1881
