.STRUCTURE IS ACTUALLY Attending To Americans to all kinds of eyeglasses. On April 8th millions watched a complete photo voltaic eclipse. Lots of will definitely be actually less charmed when, in the coming days, trillions of cicadas appear in the nation's Midwest and south-east. The flock will definitely be abnormally big due to the fact that 2 types of the pest-- Family XIII and Family XIX-- are emerging simultaneously. The last time they showed up together remained in 1803, when Thomas Jefferson was actually head of state. Why perform the cicadas possess such an unusual life cycle?