THE FALL WEB-WORM. 



253 



simply to prevent others from sharing it. A wonderful strength is necessary to perform 

 such a feat, since the caterpillar is sometimes many times as heavy as the bug itself. 

 The greediness of this bug was well illustrated in the following observations: A pupa 

 of P. spinosus had impaled a caterpillar, and was actively engaged in sucking it dry » 

 meanwhile a Wheel-hug utilized a favorable opportunity and impaled the pupa, with- 

 out forcing the same to let go the caterpillar. The elasticity of the beak (Fig. 90a) of 

 these bugs must he very great; they can bend it in any direction, and yet keep it in 

 sucking operation. The poison contained in the beak must act very rapidly, since 

 caterpillars impaled by it squirm but for a very short time, and then become quiet. 



True parasites of the Web-worm. — Telenomus MJidus Riley: A single egg of the moth 

 of R. textor is a very small affair, yet it is large enough to be a world for a little para- 

 site (Fig. 92), which undergoes all its transformations within it, and finds there all 



Fig. 92. — An egg-paraaite : a, female ; 6, tip of 

 male abdomen; c, female antenna; d, male antenna (all 

 greatly enlarged). After Riley. 



the food and lodgment required for the short period of its life. In several instances 

 batches of eggs of this moth were parasitized, and instead of producing young cater- 

 pillars 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 moth, and the larvjB pro- 

 duced soon consume the contents. This egg-parasite is a very useful friend, nipping 

 the evil in the bud, so to speak. 



Meteorus hyphantrice Riley. — This parasite (Fig. 93) has performed very good serv- 

 ices during the caterpillar plague, and has done much to check any further increase 

 of the Web-worm. During the earlier part of the summer this insect was not very 

 numerous, but sufficient proofs, in the form of empty cocoons, were observed to in- 

 dicate at least one earlier brood. Towards the end of September, and as late as the 

 15th of October, very numerous cocoons of a second brood were formed; they could 

 be found in all situations to which the caterpillar itself had access. But the great 

 majority of them were suspended from the trunks and branches of trees, and chiefly 

 from near the base of the trunk. Each cocoon represents the death of one nearly 

 full-grown caterpillar, since the latter harbors but one larva of the parasite.* A 



* In only one instance the cocoon of this parasite was found iuside of its host. 



