. Bulletin. Insects; Insect pests; Entomology; Insects; Insect pests; Entomology. surrounding tissue be flexible and moist, for the egg covering is elastic and the embryonic thrips within increases in size very noticeably before the larva issues. There is space within the adult insect's body for only a few eggs at a time—seven or eight. A thrips probably places only a few eggs dur- ing a single da3\ She feeds for a time, deposits an egg, and then moves to another place, and later to still other places, and these may be all on one or scattered on several trees. The adult thus spreads her progen
. Bulletin. Insects; Insect pests; Entomology; Insects; Insect pests; Entomology. surrounding tissue be flexible and moist, for the egg covering is elastic and the embryonic thrips within increases in size very noticeably before the larva issues. There is space within the adult insect's body for only a few eggs at a time—seven or eight. A thrips probably places only a few eggs dur- ing a single da3\ She feeds for a time, deposits an egg, and then moves to another place, and later to still other places, and these may be all on one or scattered on several trees. The adult thus spreads her progeny from tree to tree wherever she goes. Nothing seems to hinder thrips which may be set on ovipositing. They have been ob- served placing eggs at all hours of the day and night and under all conditions of weather. The period of oviposition lasts for several weeks, or during practically all of the life of the adult insects. Injury from oviposition is most conspicuous on cherry trees. Oper- ating at the base of a cluster of fruits, a few thrips will cut several incisions and place as many eggs in a single stem. This so weakens the stem that it fails to perform its usual function, and the rapidly developing cherry soon becomes yellow, and falls. Thrips seem to prefer the cherry to other varieties of fruits as a place for ovipositing during the later sea- son, and this fruit suffers severely from ovipositing, though it may escape the first feeding injury. The result is a heav}' drop- ping of half-grown cherries, which in badly infested regions means almost the whole crop. Numerous leaf and blossom stems in which eggs had been placed were closely watched to determine the length of the egg stage. In many cases these stems became dry during confinement in the laboratory, and almost in- variably from these no thrips issued. Eggs need moisture for their preservation and development, and 3^oung thrips must have tender and pliable tissue through which to emerge. The egg stage lasts, appr
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