48 OUR SHADE TREES AND THEIR INSECT DEFOLIATORS, 
In the earth of the jar were found 28 pup of Tachina flies, leaving 
76 caterpillars and 3 pupe 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 pupz 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 bifidus Riley.—A single egg of the moth of H. textor is a 
very small affair, yet it is large enough to be a world for a little para- 
site (Fig. 23), which undergoes all its transformations within it, and 
Fic. 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 egg of the 
