TRbooora 
JOURNAL OF 
THE NEW ENGLAND BOTANICAL CLUB 
Vol. 22. June, 1920. No. 258. 
THE GENUS GALINSOGA IN NORTH AMERICA. 
Hanorp Sr. Jonn AND DoNALD WHITE. 
IN his studies of the “Ferns and Flowering Plants of Nantucket,” 
E. P. Bicknell has raised to specifie rank, as Galinsoga aristulata 
Bicknell, the plant that had previously passed as G. parviflora Cav., 
var. hispida DC. This variety is distinguished from the species 
G. parviflora in the 7th edition of Gray's Manual? on having “ Pubes- 
cence more copious, not appressed; pappus-scales of the disc-flowers 
attenuate and bristle-tipped." As Bicknell points out, the name 
hispida cannot be used for the plant in the specific category because 
of the earlier G. hispida Benth. He draws contrasts between the 
plant under consideration and various species in this and related 
genera, but his only comparison between it and the very closely 
related G. parviflora is, “This now widespread weed wherever I have 
met with it has not failed to prove itself always readily distinguish- 
able from the true G. parviflora Cav., even without reference to the 
constant and pronounced differences in the pappus scales." If the 
plant does differ from its relative in a constant and pronounced 
character of the pappus-scales, as well as in vegetative characters, 
it would be reasonable to treat it as a species. "The writers became 
interested in this question, and have endeavored to verify the point. 
As is very often the case, this small question led on to the larger one, 
of checking and evaluating the characters used to separate the spe- 
cies of the genus. We found that obvious and constant characters 
existed, especially in the pappus of the ray- and disc-flowers, and we 
! Bicknell, E. P. Bull. Torr. Bot. Cl. xliii. 270 (1916). 
? Robinson, B. L., and Fernald, M. L. Gray's Man, ed, 7. 843 (1908) 
