Page:Insects - Their Ways and Means of Living.djvu/107

 GRASSHOPPER'S COUSINS

chance arrival of the next ..... -- course in his ever unfinished "' / banquet of living fare. « / ..... Some exotic species of mantids have the sides of kil II the prothorax extended to forma wide shield (Fig. 47), beneath which the forelegs are folded and completely hidden. It is not clear what advantage they derive from this device, but it seems to be one more expression of deceit. Of course, as we shall take occasion to observe

later, goodness ness are largely

FG. 48. Egg case of a mantis attached to a twig, 8ta.momantis carolina

and bad- Fro. 47. A mantis from Ecuador with matters of a shieldlike extension of its back. (Length 3' inches) relativity. The mantis is an evil creature from the standpoint of a grasshopper, but he would be regarded as a benefactor by those who have a grudge against grass- hoppers or against other insects that the mantis destroys. Hence, we must reckon the mantis as at least a beneficial insect relative to human welfare. A large species of mantis, introduced a few years ago into the eastern States from China, is now regarded as a valuable agricul- rural asset because of the number of harmful insects it destroys. The mantids lay their eggs in large cases stuck to the twigs of trees (Fig. 48). The substance of which the case is made is similar to that with which the locusts inclose their eggs, and is exuded from the

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INSECTS

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