Digging It! : Fossil Finds In Fremont County
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Charles Walcott's Discovery

The first notable discovery of Ordovician fossils in Fremont County happened in 1887. Two geologists, S. F. Emmons and T. W. Stanton, with the United State Geological Survey found some fossils while working in the Cañon City area. They sent the fossils off to the nation's leading expert on Cambrian rocks and animals, Charles D. Walcott. The fossils had similar characteristics to fossils found in New York's Upper Ordovician Limestone. Walcott discovered fragments of fishplates in the relics.

Walcott traveled to Cañon City in 1890 to examine the rock layers where the fossils came from. Two years later, Walcott reported his findings to the Geological Society. He identified two new species of fish, Astraspis desiderata and Eriptychius americanus.

Fish Scales

At one time, the Astraspis desiderata and the Eriptychius americanus were the oldest known vertebrates on Earth. Since then, paleontologists discovered fossils of older vertebrates in Australia and China. These fish inhabited the local area about 450 million years ago during the Middle Ordovician Period. Their armored plated scales covered their bodies.


Object ID:
CO-2014.51-V-42
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Astraspis and Eriptychius fossilsAstraspis and Eriptychius fossils
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