. An annotated list of the important North American forest insects. Forest insects. through the cracking skin, leaving the chrysalis hanging from the bag, as shown at r-, figure 5. The chrysalis of the female does not push its way at all out of the bag, but the skin cracks and the female gradually works her way partly out, her head reaching the lower end of the bag, (fig. 5, d). The males fly about, seeking the bags of the females, and when one is found in which the head of the female is near the end, showing that she has emerged from her chrysalis skin, the male pushes his enormously protrusi
. An annotated list of the important North American forest insects. Forest insects. through the cracking skin, leaving the chrysalis hanging from the bag, as shown at r-, figure 5. The chrysalis of the female does not push its way at all out of the bag, but the skin cracks and the female gradually works her way partly out, her head reaching the lower end of the bag, (fig. 5, d). The males fly about, seeking the bags of the females, and when one is found in which the head of the female is near the end, showing that she has emerged from her chrysalis skin, the male pushes his enormously protrusive and, in fact, telescopic genital apparatus up into the bag to the anal end of the female and fertilizes her. The female then works her way back into the chrysalis skin, gradually filling it with eggs until more than half of it is filled, scattering in among the eggs some of the sparse hairs from her body. Having done this she forces her shriveled body out of the open- ing, falls to the ground, and dies. The eggs re- main in this way until the following spring, when they hatch, as previously described. There is thus onl}- one generation annually. Note.—There is a possi- bility that the bags of this extremely common insect might be made commer- cially useful. Its silk, from a practical standpoint, has always been ignored, but it is firmer and stronger and more easily spun as carded silk than that of most other native silk Fig. 5.—Bag\V(jrm at (a, 6, c) successive stages of growth, r, Male bag; d, female bag. Natural size (from Howard). NATURAL ENEMIES. Although apparently well protected from the attacks of birds by its tough case, the bagworm is somewhat extensively parasitized b}^ several forms of ichneumon and chalcis flies, most of them species which affect also similar tree-feeding caterpillars. Prominent among these is the common Pimpla inquisitor Say (fig. 6), which, however, more commonly parasitizes the tussock moth and tent ; The relate
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Keywords: ., bookauthorhopkinsadandrewdelmar, bookcentury1900, bookdecade1900
