STUDIES IN THE COMPOSITAE. 243 
With me the Bidentidecze—or Coreopsides, if one prefer 
the more usual name—consitute a distinct tribe or subfamily 
of the Composite. 
Apparently the earliest plant of this tick-seed and dahlia 
alliance to be honored with a mention by any botanical 
author was that homely weed of Europe now known as 
Bidens tripartita. And while as yet plants were grouped 
together according to habitat, or uses, or according to 
resemblances in foliage, this type was always associated with 
another aquatic herb of similarly three-parted opposite 
leaves, namely Eupatorium cannabinum, or the genus Canna- 
bina as it was called by some. But as early as the year 
1583 Cesalpinus proposed to separate this aquatic tick- 
seed from the genus Hupatorium and to make it the type of 
a new genus which he denominated Brprens. ‘This is the 
origin of Bidens as a generic proposition; as a genus estab- 
lished upon habit, along with certain characters of flower 
and fruit; and the typeof the genus and of the subfamily 
is B. tripartita. 
2. Sketch of the History of BIDENS. 
During somewhat more than a half-century after Cesal- 
pinus this humble type which he had placed in separate 
generic rank under the name of Bidens was still, by all the 
multitude of botanists and botanical compilers, retained 
under Zupatorium as before. Then, toward the end of the 
seventeenth century,it began to be felt that this was an odd 
type to be associated with Zupatorium cannabinum, and its 
nearer relation to Chrysanthemum was suggested; after 
whieh suggestion a considerable number of authors treated 
it, and also some of its congeners then newly brought from 
America, as species of Chrysanthemum. 
PrrTONI1A, Vol. IV. Pages 243-284. Issued 26 Jan., Igor. 
