FLORA OF WASHINGTON AND VICINITY. 89 



Aster prenanthoides, Muhl. 



Cameron Run ; Great Falls. Last of September or early in October. 



Aster oblongifolius, Nutt. 



Virginia side of the Potomac below the Chain Bridge, also at Great Falls ; on 

 rocks. Last half of September and through October. 



^ Aster Novae- Angliae, L. 



Blufl's of the Potomac (rare), and sparingly in a few other localities. October. 



tDiplopappus linariifolius, Hook. [Js/er, Beuth. & Hook., Gen. PI.] Double- 

 bristled ASTEU. ^ 

 September. 



Diplopappus umbellatus, Torr. &, Gray. 

 Reform School. Sei)tember. 



Diplopappus cornifolius, Darl. 

 July to September. 



tErigeron Canadensis, L. Horse- weed. Butter- weed. 

 July, August. 



Erigeron bellidlfolius, Muhl. Robin's Plantain. Poor Robin's Plantain. 

 Middle of April to end of May. 



t Erigeron Philadelphicus, L. Fleabane. 

 Last week in Ajiril to middle of May. 



t Erigeron annuus, Pers. Daisy Fleabane. Sweet Scabious. 

 June to October. (Found as late as October 10, 1873.) 



Erigeron strigosus, Muhl. Daisy Fleabane. * 



June to August. 

 Baccharis halimifolia, L. Groundsel-Tree. 



One large branching plant found by Dr. Vasey and Professor Chickering on the 

 Aqueduct Road above Cabin John Run, September 17, 1878. 



t Filago Germanica, L. Herba Impia. 



Near Occoquan Falls, July 9, 1876; rare. Not yet found strictly within our 

 limits. 



tAntennaria plantaginifolia, Hook. Plantain-leaved Everlasting. Mouse- 

 ear Everlasting. 

 Female plants much larger than the male, often half a meter in height, and both 

 varying widely. Last of March to June. 



t Gnaphalium polycephalum, Michx. Common Everlasting. 

 April to August. 



t Gnaphalium uliginosum, L. Low Cudweed. 



Rare. Near Le Droict Park, July 20, 1873. Wet meadow, sources of Piney Branch, 



August 5, 1877. 



t Gnaphalium purpureum, L. Purplish Cudweed. 

 June to August. 



tPolymnia Canadensis, L. Leap-Cup. 

 September. 



