72 PENNELL : 



19 Aster schreberi Nees. 



Appears to be frequent here. 



20 Antennaria negtecta Greene. 



Probably common. A plant of dr}-, open fields. 



21 Helianthus grosseserratus Martens. 



Noticed by my friend, C. S. Williamson, at Secane, 

 in company with H. mollis Lam. 



The following introduced plants are additional to Dr. 

 Fussell's list : — 



1 Bromus tectorum L- 



European. Becoming frequent along railroads, etc. 

 Wawa, Lenni, Williamson. 



2 Commelina communis L. 



Asian, or also native of southern United States, if 

 identical with C. nudiflora, as Robinson and Fernald 

 assert. Abundantly introduced, apparently our only 

 species of the genus. Dr. Darlington, in the " Flora 

 Cestrica," Third Edition, 1853, notes the arrival and 

 spread of this plant in Chester County, referring it 

 doubtfull}^ and erroneously to C. ancrustifolia Michx. 

 ( = C virginica, L,. ) of the South. I have been able 

 to find no specimen from Delaware County of C. vir- 

 giyiica or of any other species, if C. midiflora be not 

 considered distinct. 



3 Fagopyrum fagopyrum (L,.) Karst. [F. esculenlnni Moench.] 



Eurasian cereal plant, occasionally appearing in cul- 

 tivated fields, or lingering after cultivation. 



4 Silene vulgaris (Moench.) (iarcke. 



[vS. lalifolia (Mill.) Britten and Rendle.] 



European. Occasional weed. Wawa. 



5 Silene dichotoma Klirli. 



Ivuropean. Occasional weed. Wawa, Newtown Square. 



