STUDIES IN THE CowrosriTAE.— VII. 
1. Some Helenioid Genera. 
Our North Ameriean plants forming the types of Gail- 
laridia, Actinella and Picradenia are possessed of no charac- 
ters of achene and pappus by which they may be distin- 
guished as genera; and the only botanist of the last half 
century who has shown any approach to consistency in the 
treatment of them was the late M. Baillon, who merged 
them allin one, under the oldest name, Gaillardia. Asa 
Gray left Gaillardia as originally constituted, but merged in 
one Nuttall’s Actinella and Hooker’s Picradenia, which was 
manifestly an inconsistency ; an arbitrary procedure, backed 
by no phytological reason whatsoever ; for Nuttall’s Actinella 
acaulis, the type of his genus, is much nearer Gaillardia 
than it is to Picradenia, both habitally and in characters of 
calyx, flowers, ete. It would have been decidedly more 
reasonableand philosophic to have followed Pursh, who never 
doubted that A. acaulis Nutt., was a true Gaillardia. 
Baillon paid no heed to habital marks as indicating ge- 
neric limits. Gray, on the other hand, professed to heed 
them, but nevertheless put Actinella and Picradenia together, 
which are as totally dissimilar in habit as any two genera 
that can be named among the,Helenioidee. They are also 
well enough fortified as separate genera, by very notable 
differences as to their involucres, as was long since pointed 
out by Sir William Hooker, and also by good characters of 
their ray-corollas, as I shall indicate. 
Actinella as employed by Nuttall and by Gray is a homo- 
nym. Persoon had early applied it to a different genus. Ra- 
finesque’s Ptilepida is but a synonym of Persoon’s (not Nutt- 
all's) Actinella; and its use, attempted in the recent Check | 
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