. Bulletin. Insects; Insect pests; Entomology; Insects; Insect pests; Entomology. 48 OUR SHADE TREES AND THEIR INSECT DEFOLIATORS. lu the earth of the jar were found 28 pupae of Tachiua flies, leaving 76 caterpillars and 3 pupiij killed by fungus, or 63 per cent. In both experiments it has been assumed that each Tachina fly had killed one caterpillar. On November 15, 1886, the jars were again investigated, and it was found that a number of the iiuptB had been killed by the fungus since October 18, 1886, and that in fact all the remaining ones did not look healthy. The percentage of death by th
. Bulletin. Insects; Insect pests; Entomology; Insects; Insect pests; Entomology. 48 OUR SHADE TREES AND THEIR INSECT DEFOLIATORS. lu the earth of the jar were found 28 pupae of Tachiua flies, leaving 76 caterpillars and 3 pupiij killed by fungus, or 63 per cent. In both experiments it has been assumed that each Tachina fly had killed one caterpillar. On November 15, 1886, the jars were again investigated, and it was found that a number of the iiuptB had been killed by the fungus since October 18, 1886, and that in fact all the remaining ones did not look healthy. The percentage of death by the fungus in the two experi- ments was thus increased to 63 per cent, in Experiment I and to 67 per cent, in Experiment II. TRUE PARASITES OF THE WEB-WORM. Telenomus hijidus Riley.—A single egg of the moth of H. textor is a very small aifair, yet it is large enough to be a world for a little para- site (Fig, 23), which undergoes all its transformations within it, and. Fig. 23.—An egg-parasite: a, female; b, tip of fe- male abdomen; c, female antenna; d, male antenna (all greatly enlarged). finds there all the food and lodgment required for the short period of its life. In several instances batches of eggs of this moth were para- sitized, and instead of producing young caterpillars they brought forth the tiny insects of this species. The batches of parasitized eggs were found July 27 upon the leaves of Sunflower, and August 18 upon leaves of Willow; judging from these dates it was the second brood of moths that had deposited them. There can be no doubt, however, that eggs produced by moths emerging from their cocoons in early spring had been parasitized as well. The female Telenomus was also observed, August 2, busily engaged in forcing its ovipositor into the eggs, and depositing therein. The female insect is so very intent upon its work that it is not easily disturbed, and one can pluck a leaf and apply a lens without scaring it away. The eggs soon hatch inside the large eg
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