National Geographic : 1953 Jul
Lobsterlike Claws Serve Rip Van Winkle While Underground This summer, woods in Samany parts of the eastern United States echo with the shrill wail of the pe riodical cicada, mistakenly called the 17-year locust. A few of the insects ap pear every year, but 1953 sees emergence of the largest and most wide spread group, Brood X. This year's brood was born in 1936 and went underground immediately. For 17 years the slowly maturing nymphs lived quietly in earthen cells, sucking sap from roots. Now, as if by a secret signal, the homely earth dwellers have swarmed in myriads to the surface. Transforming overnight into ornate winged adults, they flit briefly but loudly in the sunshine, to mate and lay eggs before they die. This nymph, just out of r the ground, waves formi dable digging claws. En largement (below) shows how these powerful tools combine pick, rake, and mallet with which the ci cada tamps freshly dug soil into burrow walls. Dig ging claws give way to or dinary forelegs in the adult insect. :Moody Institute of Science 134 The homely milk-and-coffee-colored nymph with glaring blood-red eyes re sembles a small crayfish as he lumbers unaccustomedly across the ground. His oversized front claws, so useful for tun neling, he now puts to a different use. With single-minded intent, the cicada nymph heads for a near-by tree or post. Climbing part way up, he anchors his claws into bark or leaves, repeatedly test ing his toe hold. Spectral Shells Sway in the Breeze Now his back arches; he contorts vigor ously. Suddenly a split shoots up the back of his shell. As the convulsions continue and the split widens, a creamy-white specter slowly pulls itself free, leaving the empty chitinous husk clinging to the sup port (pages 138, 139, and 142). This is the adult. Baleful red eyes and velvet-black shoulder patches stand out against the white. Curved claws like a lobster's, no longer needed for digging, have given way to slender forelegs.