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In the winged state Cicada septendecim, as the subject of our sketch was named by the immortal Linnæus, is of a black color, with transparent wings and wing-covers, the thick anterior edge and veins of which being orange-red. Near the tips of the latter there is a dusky zig-zag line which resembles in shape the letter W. The eyes, when living, are also red, while the legs are a dull orange, which color is conspicuous along the edges of the rings of the body. The wings expand from two and a half to three and a quarter inches.
SEVENTEEN-YEAR CICADA.
Adult, Chrysalis-Case, Pupa, Entrances to Burrows and Egg-Nests.
About the middle of June the perfect insects make their appearance, and as they generally come in large numbers they do a great deal of damage. In some localities they congregate to such an extent upon the trees as to bend and even to break down the limbs by their weight. The din of their discordant drums resounds in the woods and orchards from morning to evening. As their life is of rather short duration, not lasting for a longer period than a month, they soon begin to pair, and it is not long afterwards that the females may be seen preparing nests for the reception of their eggs. Branches of moderate size are selected for this purpose. Their manner of perforation is curious and interesting. Clasping the branch on both sides with their legs, and bending the ovipositor at an angle of forty-five degrees, they repeatedly thrust it into the bark and wood in the direction of the fibres, at the same time setting the lateral saws at work, thereby detaching little splinters of wood at one end, which are intended to serve as a kind of fibrous cover for the nest. The hole is bored obliquely to the pith, and by a repetition of the same operation is gradually enlarged until is formed a longitudinal fissure of sufficient extent to receive from ten to twenty eggs. The side-pieces of the piercer act as a groove to convey the eggs to the nest, where they are deposited in pairs, but separated from each other by a narrow strip of wood. When two eggs have been thus placed, the piercer is withdrawn for a moment, and then inserted till two more eggs are dropped in a line with the first, and thus the operation is repeated until the fissure has been filled, when the insect removes to a little distance and commences to make another nest to contain two more rows of eggs. It takes about fifteen minutes to prepare a groove and fill it with eggs. As many as twenty grooves are sometimes made in a branch by a single insect, and when the limb has been sufficiently stocked she goes from it to another, or from tree to tree, until she has got rid of her complement of from five hundred to seven hundred eggs. So weak does she at length become, in her continued endeavor to provide for the succession of her race, as to fall, in an attempt to fly, an almost lifeless lump to the earth, where her spirit soon goes out never more to enliven its frail house of clay.