Elementary textbook of economic zoology Elementary textbook of economic zoology and entomology . elementarytextbo00kell Year: [c1915] THE CLASSIFICATION OF INSECTS 181 smallest insects known to others two inches or more in length. Some of these minute parasites lay their eggs within the eggs of other insects, and their larvae live their whole lives in the con- tents of these host eggs, but most Hymenopterous parasites deposit their eggs on the skin of the larvae or nymphs of other insects, especially on caterpillars. The parasite larvae, on hatching, bore their way through the skin into th
Elementary textbook of economic zoology Elementary textbook of economic zoology and entomology . elementarytextbo00kell Year: [c1915] THE CLASSIFICATION OF INSECTS 181 smallest insects known to others two inches or more in length. Some of these minute parasites lay their eggs within the eggs of other insects, and their larvae live their whole lives in the con- tents of these host eggs, but most Hymenopterous parasites deposit their eggs on the skin of the larvae or nymphs of other insects, especially on caterpillars. The parasite larvae, on hatching, bore their way through the skin into the host body and remain there, feeding on the blood lymph and perhaps on other body tissues. The host dies, but usually not until the parasites have com- pleted their larval life and have changed to pupae either within the host's body, or have issued from it and pupated outside. Parasitized caterpillars are often able to pupate, but from their pupa there issues, not a moth or butterfly, but many of the little four-winged parasites. These fly freely about, mate, and then deposit their eggs on the body of other hosts. A few members of this group are not parasites but gall-makers. Among these qnisitor, laying egg in an important kind is the curious small fig- cocoon of American /n; Li \ r. t_- i_ o tent-caterpillar moth. wasp (Blastophaga) by which the Smyrna (About natural size; figs are cross-pollinated and made to set after Fiske.) seed and thus to become especially palata- ble. The fig-wasp has been introduced from Asia Minor into California, and has greatly added to the value of California figs. Third, the family Cynipida or gall-flies, some of which are parasites, but most of which thrust their eggs, by means of a sharp ovipositor, into the leaves or green stems of oaks, roses and a few other plants, so that the hatching larvae find them- selves surrounded by rich plant food. The presence of the larva stimulates the plant to a vigorous production of new tissue about it,
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