.STRUCTURE IS Caring For Americans to all kinds of spectacles. On April 8th thousands observed a complete solar eclipse. Many will certainly be much less knocked out when, in the coming times, trillions of cicadas appear in the country's Midwest and south-east. The flock will definitely be unusually big because pair of kinds of the insect-- Brood XIII as well as Family XIX-- are developing at the same time. The last opportunity they appeared at the same time remained in 1803, when Thomas Jefferson was president. Why perform the cicadas have such an unique life cycle?