The cicadas, or seventeen-year locusts, are the longest-lived insects. They spend almost their entire seventeen year life span in the pupal stage of development, living under-ground, feeding on the juices of tree roots. 
     Then, in the seventeenth summer of their lives, that entire generation emerges, almost at once, molts into the winged adult stage, sings, mates, lays eggs, and dies within a few weeks' time. 

Cicadas cicadas cicadas cicadas

         everywhere in the brush
clinging to leaves
in their tanned leather ditch digger's

Oh no, that's not you
         just empty cases
cast off life masks

Now I see you
         red-eyed, black-hulled
with tiny wrinkled dragon wings
drying -- expanding into
                  lead and glass lace

And there you are with ready wings
launching yourself into
         the great heights of the basswoods
A metallic rain of sound shimmers
                  the sun-hot afternoon air

Cicadas cicadas cicadas cicadas

It was a summer more than half
                                  my life ago
when I heard the preceding generation
          of your kind
trilling their readiness to complete
                   their lives
They were my elders then
and their readiness preceded mine

But now you of the ensuing brood
                                  are trilling
with a readiness
still far preceding mine