Archæan

( Geol. ) Pertaining to or characteristic of the oldest geological period containing stratified rocks, those being granitoid gnei es and crystalline schists. It is sometimes divided into the Azoic and the Eozoic periods, the former being without fo ils, the latter containing what may be the earliest fo ils, though their fo iliferous character is greatly doubted. It is also divided into the Lauren tian and the Huronian periods, including all stratified rocks earlier than the Cam brian. The Upper Huronian rocks are now called Algonkian (q.v.) by the U. S. Geological Survey, the term Archæan being restricted to rocks of earlier date.