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Jefferson National Expansion MemorialPediment above door on the Old Courthouse exterior
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Jefferson National Expansion Memorial
Photo Album November 7, 1805
Dinosaur cartoon  

Did You Know?
On September 10, 1804 on Cedar Island, in South Dakota, William Clark discovered the fossilized remains of the ribs, backbone and teeth of a plesiosaur. Plesiosaurs were animals who lived at the same time as the dinosaurs, but swam rather than walking on land. Clark thought it was a giant fish bone!
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Last Updated: February 13, 2009 at 16:38 EST