| Rocks at right to center belong to the extratraordinarily fossiliferous middle to late Devonian Guilmette Formation, White Pine County, Nevada. The Guilmette Formation yields prodigious quantities of Paleozoic Era invertebrate animal remains: corals, stromatoporoids (extinct calcareous sponge), gastropods, brachiopods, crinoids, ostracods, and conodonts. |