Page:Popular Science Monthly Volume 92.djvu/687

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PopnTar Science Monfhli/

��071

���The first picture shows the Pigeon-Tremex, which destroys trees by boring into them. The second shows the Ichneumon Fly which destroys the destroyer, thereby saving the trees

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��Even a Parasite May Prove to Be Useful to Man

►Z-Z-Z-." "Bz-z-z-z-z"— the buzzing sound comes nearer. It is produced by the vibrations of the wings of a most peculiar looking insect. Its body is about two and a half inches in length, with transparent wings marked with dark spots. Hanging straight down from the rear end of the slender body is a thin, hair- like something, about five or six inches long, which seems to interfere with flight.

Clumsily the insect circles around the trunk of the big elm tree. The buzzing ceases. The insect crawls around the trunk for some time before it stops.

Without further preliminaries the queer insect raises its threadlike appendage straight up, then curves it in form of a loop over its back, so that the sharp tip at the end of it comes down on the bark. The appen- dage, which seems to have the rigidity of a steel wire, is planted perpen- dicularly upon the trunk and is dril- ling a small hole into it with sur- prising rapidity. At last the drilling ends. With uner- ring instinct the in- sect, known as the Ichneumon Fly, has located the burrow of another insect, the large Pigeon-Tremex,

��belonging to the insect family known as Horn-Tails. The female has drilled through bark and wood with its slender ovipositor until it reached the burrow. It deposits one egg in it.

The Ichneumon Fly is a parasite. It deposits its eggs in the burrows of the Tremex and its larvae, which develop from the eggs in a short time, feed upon and kill the larvae of the Tremex which they find in the burrow. It is the female of the Tremex which drills the tell-tale holes into the bark of our shade trees and deposits eggs in them. The larvae which come from these eggs burrow into the heartwood of the tree unless their career is cut short by an Ichneumon larva.

���This ferocious hon Virginia creeper — (

��Reducing the High Cost of Build- ing with Camouflage Lions

MOSES HAMBUR- GER, of Los An- geles, built himself a new house, and his soul lusted after lions to guard the portals thereof. Accordingly he had built nice inexpen- sive bodies of laths, fitting them with faces of concrete. Then he planted Virginia creeper with the result that he now has two m.agnificent camouflaged lions.

��is made of laths and

heaper than bronze

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