This paper presents an attempt to work out the varieties which may be recognized in Erigeron foliosus Nutt., a species which shows remarkable variation with great intergradation between its varieties, but for the most part distinct from other species. It does intergrade with E. Breweri Gray, especially in those forms where the corymbs become reduced. In general the specific diagnostic characters used by Jepson (Man. Fl. Pis. Calif., 1051. 1925) are quite satisfactory.