Page:Insects - Their Ways and Means of Living.djvu/54

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Insects


and hide. As becomes a carnivorous creature whose prey must be industriously sought, they display great powers of endurance, and will survive for a fortnight without food in a moderate temperature. Yet in the search for locust eggs many are, without doubt, doomed to perish, and only the more fortunate succeed in finding appropriate diet.

Reaching a locust egg-pod, our triungulin, by chance, or instinct, or both combined, commences to burrow through the mucous neck, or covering, and makes its first repast thereon. If it bas been long in search, and its jaws are well hardened, it makes quick work through this porous and cellular matter, and at once gnaws away at an egg, first devouring a portion of the shell, and then, in the course of two or three days, sucking up the contents. Should two or more triungulins enter the same egg-pod, a deadly conflict sooner or later ensues until one alone remains the victorious possessor.

The surviving triungulin then attacks a second egg and more or less completely exhausts its contents, when, after about eight days from the time of its hatching, it ceases

Fig. 13. The second-stage larva of the striped blister beetle.
(Frorn Riley)

from its feeding and enters a period of rest. Soon the skin plits along the back, and the creature issues in the second stage of its existence. Very curiously, it is now quite different in appearance, being white and soft-bodied and having much shorter legs than before (Fig. 13). After feeding again on the eggs for about a week, the creature molts a second time and appears in a still different form. Then once more, and yet a fourth time, it sheds its skin and changes its form. Just before the fourth molt, however, it quits the eggs and burrows a short distance into the soil, where it composes itself for a period of retirement, and here undergoes another molt, in which the skin is not cast off. Thus the half-grown insect passes the winter, and in spring molts a sixth time and becomes active again, but not for long—its larval life is now about to close, and with another molt
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