FLORA OF WASHINGTON AND VICINITY. 91 



tHelianthus strumoaus, L. 

 Not common. September. 



Heliauthus strumosus, L., var. mollis, Gray. 



P'orms of the precediug with the under surface of the leaves quite downy occur, 

 and may be referred here. September, 



Helianthus divaricatus, L. 



July. 



tHelianthus decapetalus, L. 



July, August. 



Helianthus doronicoides, Lam. 

 September. 



HeUanthus tuberosus, L. Jerusalem Artichoke. 



Waste places in the city. Late in September and in October. 



tActinomeris squarrosa, Nutt. 

 September. 



Verbesina Siegesbeckia, Michx. Crownbeard. 



September. 



Coreopsis tinctoria, Radius. Tickseed. 

 Escaped in a few places. June. 



t Coreopsis verticillata, L. Whorled Coreopsis. 

 Middle to end of June. Well worthy of cultivation. 



t Coreopsis tripteris, L. Tall Coreopsis. 



Bluffs below Chain Bridge, Va., High Island, and near Langley. August. 



Coreopsis discoidea, Torr. & Gray. 

 Holmead Swamp. September. 



tBidens frondosa, L. Common Beggar-ticks. 

 August, September. 



tBidens cernua, L. Smaller Bur-Marigold. 

 Very variable. September, October. 



tBidens chrysanthemoides, Michx. Larger Bur-Marigold. 

 July, August. 



tBidens bipinnata, L. Spanish Needles. 

 August, September. 



tHelenium autumnale, L. Sneeze-weed. Autumn Sneezewort. 



August, 

 t Achillea Millefolium, L. Yarrow. Milfoil. 



June. 



Authemis arvensis, L. Corn Chamomile. 



May to October. 

 tMaruta C'o<u/rt, DC. [^wrtemts, Benth. & Hook., Gen. PL] May-weed. 



Rare. May, June. 



