. Bulletin. Insects; Insect pests; Entomology; Insects; Insect pests; Entomology. 32 OUR SHADE TREES AND THEIR INSECT DEFOLIATORS. manuer, instead of the narrow girdling' band, had had the bark inegu- hirly removed for tlie extent of an inch or more. All these later falling twigs showed the interval that had elapsed between the injury and the fiill, in that the roughened edges of the bark left by the gnawing had healed over with the peculiar roughened and rounded enlargement fol- lowing the deposit of the reparative material under such conditions. Some of the twigs gathered gave excellent illu
. Bulletin. Insects; Insect pests; Entomology; Insects; Insect pests; Entomology. 32 OUR SHADE TREES AND THEIR INSECT DEFOLIATORS. manuer, instead of the narrow girdling' band, had had the bark inegu- hirly removed for tlie extent of an inch or more. All these later falling twigs showed the interval that had elapsed between the injury and the fiill, in that the roughened edges of the bark left by the gnawing had healed over with the peculiar roughened and rounded enlargement fol- lowing the deposit of the reparative material under such conditions. Some of the twigs gathered gave excellent illustration of the ascent of the sap through the outer wood, and its return, after assimilation in the leaves, through the inner bark. In one instance, where the leaves were unusually large, the descending sap, arrested at the girdled iwint, had built ui) structure in the tip until its diameter was more than double that of the starved internode below, while the immediate point of the arrest was quite enlarged from the material there deposited. "This peculiar attack did not extend to the other principal food- l)lants of the Orgyia, as the horse-chestnut, maple, apple and i)lum, nor would it be (expected to occur in connection with growth and struct- ure so different from that of the ; Pup'iiion.—Six days after the third molt a portion of the larva^ spiu up; all these produce male moths. The female caterpillars, which up to this time have been undistinguishable from the male caterpillars, undergo a fourth (and, as it appears from more recent experience, in some instances even a fifih) molt and acquire twice the size of the male caterpillar. This last, when full grown, measures about liO milli- meters in length. The cocoon spun by the male caterpillar is of whitish or yellowish color and sufficiently thin to show the insect within. It consists of two layers, the hairs of the tufts and brushes of the cater- pillar being interwoven with the outer layer. The female cocoo
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