Paleozoic Era Cambrian Period Ordovician Period Early Ordovician Epoch Middle Ordovician Period Late Ordovician Period Silurian Period Llandovery Epoch Rhuddanian Age Aeronain Age Telychian Age Wenlock Epoch Ludlow Epoch Pridoli Epoch Devonian Period Carboniferous Period Permian Period
Arctinurus boltoni (Bigsby)
Subclass Trilobita Order Lichida Family Lichidae
Rochester Shale, Lewiston Member
Middleport, New York, USA
(scale bar in cm)
