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large oval cocoon of which is a conspicuous object in the winter on the twigs of our common shade and fruit trees. Many other pupae may be found beneath logs or on the under side of bark, and usually have the chrysalis surrounded by a thin covering of hairs, which are rather loosely arranged. A number pass the cold season in the earth with no protective covering whatever. Among these is a large brown chrysalis with a long tongue case bent over so as to resemble the handle of a jug. Every farm boy has ploughed or spaded it up in the spring, and is it but the pupa of a large sphinx moth, _Protoparce celeus_ Hub., the larva of which is the great green worm, with a "horn on its tail," so common on tomato plants in the late summer. [Illustration: CHRYSALIS OF TOMATO WORM.] Each of the winter forms of insects above mentioned can withstand long and severe cold weather--in fact, may be frozen solid for weeks and retain life and vigor, both of which are shown when warm weather and food appear again. Indeed, it is not an unusually cold winter, but one of successive thawings and freezings, which is most destructive to insect life. A mild winter encourages the growth of mould which attacks the hibernating larvae and pupae as soon as, from excess of rain or humidity, they become sickly; and it also permits the continued activity of insectivorous mammals and birds. Thus, moles, shrews, and field mice, instead of burying themselves deeply in the ground, run about freely during an open winter and destroy enormous numbers of pupae; while such birds as the woodpeckers, titmice, and chickadees are constantly on the alert, and searching in every crevice and cranny of fence and bark of tree for the hibernating larvae. Of the creeping, wingless creatures, which can ever be found beneath rocks, rails, chunks, and especially beneath those old decaying logs which are half buried in the rich vegetable mould, the myriapods, or "thousand-legs," deserve more than a passing notice. They are typical examples of that great branch of the animal kingdom known as _arthropods_, which comprises all insects and crustaceans. Each arthropod has the body composed of rings placed end to end and bearing jointed appendages, and in the myriapods each ring and its appendages can be plainly seen; whereas in the higher forms of the branch many of the rings are so combined as to be very difficult to distinguish. Full forty kinds of myriapods occur in any area
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