This entry describes one of 30 specimens that were sent to President Jefferson from Fort Mandan and then logged into the Museum in Philadelphia on November 16, 1805, but subsequently lost. We include this species as an example of the breadth of discovery and the explorers’ scholarship; attribution to this species is based upon Lewis’ description, early botanical work on the specimens, current botanical literature, and knowledge of the regional flora.
Capt. Lewis, May 27, 1804 - No. 5. was taken on the 27th of May 1804, near the mouth of the Gasconade; it is a species of cress which grows very abundantly alonge the river beach in many places; my men make use of it and find it a very pleasant whol[e]some sallad.
Several Rorippa species have been suggested for this entry. We have listed and illustrated R. sinuata as a species that might not have been familiar to them east of the Mississippi, but is found in the Missouri River valley.