INSECTS
egg, so that the skin may be left sticking in the open end of the shell. If the young cicada did not have to gain its liberty through that narrow corridor, it might be born in a smooth bag as are its relations, the aphids.
Watching at the door of an undisturbed nest during a hatching day, we soon may see a tiny pointed head come poking out of the narrow hole. The threshold is soon crossed, but no more; this traveling in a bag is not a pleasure trip. A few contortions are always necessary to rupture the skin, and sometimes several minutes are consumed in violent twistings and bendings before it splits. When it does break, a vertical rent is formed over the top of the head, which latter bulges out until the cleft becomes a circle that enlarges as the entire head pushes through, followed rapidly by the body (Fig. 125, 4). The appendages come out of their sheaths like fingers out of a glove, turning the pouches outside in. The antennae are free first; they pop out and hang stiffly downward. Then the front legs are released and hang stiff and rigid but quivering with a violent trembling. In a second or so this has passed, the joints double up and assume the characteristic attitude, while they violently claw the air. Then the other legs and the abdomen come out and the embryo is a free young cicada (7). All this usually happens in less than a minute, and the new creature is already off without so much as a backward glance at the clothes it has just removed or at the home of its incubation period. Sentiment has no place in the insect mind.
As the nymphs emerge from the nest, one after another, and shed their skins, the glistening white membranes accumulate in a loose pile before the entrance, where they remain until wafted off on the breeze. Each discarded sheath has a goblet form (Fig. 125, 5, 6), the upper stiff part remaining open like a bowl, the lower part shriveling to a twisted stalk. The antennal and labral pouches project from the skin as distinct append-
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