Nuttall, Thomas, 1786-1859: Avid, expert, and intrepid collector, plant taxonomist, botanical writer, ornithologist, and Professor.  Came to the U.S. from England in 1807 and in 1808 met, learned from, and began making collecting trips for famed University of Pennsylvania Professor and naturalist, Benjamin Barton. In 1810 on Nuttall's third Barton collecting trip, this one to the Great Lakes, he learned of a John Jacob Astor Company trip up the Missouri, headed to St. Louis instead of to Philadelphia and Barton, and in the spring of 1811 headed West on a collecting journey. 

Nuttall collected along the route the Lewis and Clark Expedition had covered, but whereas Nuttall's collection made it East to be studied; much of Lewis' collection was lost.

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