Barbarea orthoceras Ledeb.
There are three documented records for this species in Maine. It was collected along the St. John River in Ft. Kent in 1880 by Kate Furbish and in 1898 by Fernald, from a gravel shore in St. Francis in 1893 by Fernald, and from a sandy meadow in Skowhegan in 1903 by Chamberlain.
Synonyms: Barbarea americana Rydb.; Barbarea orthoceros Ledeb. var. dolichocarpa Fern.; Campe orthoceras (Ledeb.) Heller