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 When two eggs have been thus placed, the piercer is withdrawn for a moment, and then inserted till two more eggs are dropped in a line with the first, and thus the operation is repeated until the fissure has been filled,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.

Although Cicadas abound most upon the oaks, yet there seem to be no trees or shrubs that are exempt from their attacks, unless it be the various species of pines and firs. The punctured limbs languish and die soon after the eggs are laid, and as often happens are broken off by the winds; but when this is the case the eggs never hatch, for the moisture of the living branch seems necessary for their proper development.

The eggs are one-twelfth of an inch in length, and onesixteenth of an inch through the middle, but taper to an obtuse point at each end. They are of a pearl-white color. The shell is so thin and delicate that the form of the inclosed insect can be seen before the egg is hatched. One writer claims that fifty-two days, and others that fourteen days, constitute the period required for the hatching of the egg. When it bursts the shell the young insect is one-sixteenth of an inch long, and is of a yellowish-white color, excepting

the eyes and the claws of the fore-legs, which are reddish. It is clothed with small hairs. In form it is grub-like, larger proportionally than the parent, and provided with six legs, the first pair being very large, shaped like lobster-claws, and armed beneath with strong spines. Little prominences take the place of wings, and under the breast is a long beak for suction. Its movements, after leaving the egg, are very lively, and nearly as quick as some of the ants. But after a few moments their instincts prompt them to reach the ground. They do not attain this end by descending the body of the tree, nor by casting themselves off precipitately, but, running to the side of the limb, deliberately loosen their hold and drop to the ground, making the perilous descent with the utmost safety. This seems almost incredible, but it has been repeatedly observed by scores of honest witnesses.

NEW-BORN CICADA.

Line Below Shows Natural Size.

On reaching the ground the young insects immediately burrow their way into the soil, using their broad and strong fore-feet pretty much after the fashion of the mole. They apparently follow, in their descent, the roots of plants, fastening their beaks into the most tender and succulent, and thus imbibing their juices, which constitute their sole aliment. They do not descend very deeply into the ground, probably not more than ten or twelve inches, although accounts have been published of their discovery at a depth of ten or twelve feet, but their occurrence at such great distances from the top of the ground is doubtless the result of accident.

The only alteration to which the insects are subject during the seventeen years of their subterranean confinement, is an

increase in size, and the more complete development of the four small scale-like prominences of the back, which contain their future wings.

When the time of its transformation draws near, the larva, in which stage the insect passes the greater part of its existence, works its way up towards the surface, oftentimes in a very circuitous manner, for local changes make it necessary for it to bore through hard woods and between stones well beaten down. The burrow which it thus produces is cylindrical, about five-eighths of an inch in diameter, and firmly cemented and varnished so as to be water-proof. The upper portion, to the extent of five or six inches, is empty, and serves as a habitation till the period of its exit arrives, while the lower is filled with earthy matter removed by the insect in its progress. In this cell it remains during several days, ascending to the top for the benefit of the sunshine and air when the weather is auspicious, even venturing to peep forth occasionally, but descending on the occurrence of cold or wet weather. But when the favorable moment to leave their subterranean retreats arrives, the Cicada-grubs, or more properly pupæ, for such they are now to be considered, although they still retain something of the grub-like form, issue from the ground in great numbers as evening draws on, crawl up the trunks of trees, the stems of herbaceous plants, or on to whatever is convenient, which they grasp securely with their claws. After resting awhile, their skins, which have become dry and of an amber color, are by repeated exertions rent along the back, and through the slit formed the included Cicada pushes its head and body, and withdraws its wings and legs from their separate cases, and, crawling to a short distance, leaves its empty pupa-case fastened to the tree. At first the wing-covers and wings are small and opaque, but in a few hours they acquire their natural size and shape. It is not, however, for three or four days that the muscles harden sufficiently for them to assume their characteristic flight. The males make their appearance

DOME-LIKE HOUSE OF CICADA

Longitudinal Section Showing Pupa in Tw, Positions

some days in advance of the females, and also disappear sooner. During several successive nights the pupæ continue to issue from the ground, and in some places, as was the case in May of 1868, when these insects appeared in great numbers in the vicinity of Philadelphia, the whole surface of the soil was made by their operations to assume a honey-combed appearance.

In localities where the soil is low and swampy, a remarkapie chamber is built up by the larva, where the pupa may be found awaiting the time of its change to the winged state. These chambers were first noticed by S. S. Rathvon, at Lan caster, l'a., and are from four to six inches above the ground, and have a diameter of one inch and a quarter. When ready to emerge the insect backs down to an opening which is left in the side of the structure on a level with the surface of the ground, issues forth and undergoes its transformation in the usual manner. This peculiar habit of nest building, which is so unlike what is customary with the Ciuide, or with Hemiptera in general, points to a high degree of inte gence among these insects, showing a cartabl adapt themselves to eni ning rin

seemed to know, through the guidance of the same dumb and unerring instinct which teaches it to cement its underground dwelling, but would that same instinct teach it to construct so wonderful a dome-like house as the one described for the preservation of its after-life, and one so eminently fitted by its position, shape, size and entrance to secure the necessary shelter, warmth and air for its protection and development? I apprehend not. Nothing short of a reason, similar to that in man, but differing in degree, would enable it to grasp the situation in which it found itself to be placed when nearing its final change, and plan with the view of carrying out the ultimate aim of its existence.

Fortunately, these insects are appointed to return at periods so distant that vegetation has a chance to recover from the injuries which they inflict. Were they to appear at shorter intervals, our forest- and fruit-trees would be entirely destroyed by them. They are, moreover, subject to many accidents, and have many enemies, which contribute to diminish their numbers. Their eggs are eaten by birds, and the young, when they leave the egg, are preyed upon by ants, who mount the trees for that purpose, or take them upon the ground as they are about to enter upon their protracted larval career. Blackbirds eat them in the spring when turned up by the plough, and hogs, when allowed to run at large in the woods, root them up and devour large numbers, especially just before the arrival of the period of their final transformation, when they are lodged only a few inches below the surface of the soil. Many perish in the egg by the closing up of the bark and wood that constitute the walls of the perforations, thus burying the eggs before they have hatched, and others, no doubt, are killed by their perilous descent from the trees.

As its name implies, this insect generally requires seventeen years to complete its transformations, a fact that was first pointed out many years ago by the botanist Kalm. The late Prof. Riley, who had given this species a great deal of