. Ontario Sessional Papers, 1919, . Fig. -Leaf injury caused bypear psylla. Fig. 15.—Leaves showing honey-dew fungus andnymphs. Life Histoey, Summary. The winter is passed in the adult stage. The adults hibernate under the roughbark on the trunks and main limbs, and under grass, leaves and rubbish near theinfested pear trees. In late March or early April the insects leave their winterquarters, congregate on the twigs and fruit spurs and in a short time, providedthe weather remains propitious, commence to lay eggs. Oviposition may continueuntil about the time the petals drop; howe
. Ontario Sessional Papers, 1919, . Fig. -Leaf injury caused bypear psylla. Fig. 15.—Leaves showing honey-dew fungus andnymphs. Life Histoey, Summary. The winter is passed in the adult stage. The adults hibernate under the roughbark on the trunks and main limbs, and under grass, leaves and rubbish near theinfested pear trees. In late March or early April the insects leave their winterquarters, congregate on the twigs and fruit spurs and in a short time, providedthe weather remains propitious, commence to lay eggs. Oviposition may continueuntil about the time the petals drop; however, the vast majority of the eggs arelaid by the time the fruit buds have burst. The eggs are deposited on the twigs,fruit spurs and smaller branches, chiefly on the under surface. They commenceto hatch when the fruit buds are beginninof to break, and nearly all have hatched 1919 ENTOMOLOGICAL SOCIETY 83 by the time the petals drop. The period of incubation varies, according to thetemperature, from 8 to 33 days, the average being about t
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