Economic entomology for the farmer and fruit-grower [microform] : and for use as a text-book in agricultural schools and colleges . economicentomolo00insmit Year: 1896 [/ 274 AN ECONOMIC ENTOMOLOGY. \\\ the spring these eggs hatch, and the httle larvae make their way out through the mouth of the bag and feed upon the leaves, at once constructing for themselves a case made of leaf fragments held together with silken threads. At this time the bags are carried upright, and the insects feed on the upper surface of the leaf As the larva grows it enlarges its habitation, which soon becomes too heav
Economic entomology for the farmer and fruit-grower [microform] : and for use as a text-book in agricultural schools and colleges . economicentomolo00insmit Year: 1896 [/ 274 AN ECONOMIC ENTOMOLOGY. \\\ the spring these eggs hatch, and the httle larvae make their way out through the mouth of the bag and feed upon the leaves, at once constructing for themselves a case made of leaf fragments held together with silken threads. At this time the bags are carried upright, and the insects feed on the upper surface of the leaf As the larva grows it enlarges its habitation, which soon becomes too heavy to be maintained in an upright position, and Fig. 298. The bag-worm, Thyridopteryx ephetnercsformis.—a, larva; b, male pupa; c, female; d, male moth; e, bag of female cut open to show the mass of eggs ; f, caterpillar with bag in normal position ; g-, young larvae with bags carried upright. drops ; the insect continues to feed, attaching the bag by means of silken threads to twigs when not moving about from place to place. Late in summer the larvae become full grown, and wander, sometimes leaving the trees altogether and fastening to fences or other shelter in the vicinity, and it is this habit that provides for the spread of the insects. When they have reached a place that suits them, the bags are firmly fastened, the opening is closed, and the caterpillars change to pupae. Shortly after the male emerges, and this is a black moth with transparent wings, short, feathered antennae, and an unusually long, tapering body. It is quite active and seeks the female, which forms only an imperfect sort of pupa, and even in the adult condition is a non- descript without trace ot wings and almost without antennae.
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