Page:Popular Science Monthly Volume 5.djvu/174

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THE POPULAR SCIENCE MONTHLY.

The next most efficient aid in the destruction of the leaf-lice is found among the lace-wing flies, one species of which, more especially, viz., the Weeping Lace-wing (Chrysopa plorabunda Fitch), I find very frequently within the galls, devouring their contents. These

Fig. 1.

Thrips.

flies are known as well by their brilliantly golden eyes as by the peculiarly offensive odor, as of human ordure, which some of them emit. The eggs are adroitly deposited (Fig. 2, a) by the parent at the tips of long silk-like stalks, in order to prevent first-born larvæ from exercising

Fig. 2.

Lace-wing fly.—a, eggs; b, larva; c, cocoon; d, fly, the wings to the left omitted.

their cannibalistic propensities on their yet unborn brethren. The larva (Fig. 2, b) is very rapacious, and, when ready to transform, winds itself up into a wonderfully small cocoon (considering the size of the insect which makes it and which issues from it), which is spun

Fig. 3. Fig. 4.
Convergent Ladybird; a larva, pupa, and beetle. Syphius Larva.

from the extremity of the body, and from which it issues, when about to acquire wings, through a neatly-cut, circular aperture. Next in order, as Phylloxera enemies, may be mentioned the Ladybirds (Cocci-