a a dandis 
1901] Greenman, — Senecio in New England 3 
THE GENUS SENECIO IN NEW ENGLAND. 
J. M. GREENMAN. 
AMONG the flowering plants there are few genera more widely dis- 
tributed throughout North America than is the genus Senecio. In 
New England the indigenous species with but one exception (.S. 
Pseudo-Arnica, Less.) all belong to the same natural group, and ex- 
hibit very close affinity. 
The first species of this genus to be described from North America 
were S. aureus L., S. Ba/samitae, and S. obovatus, Muhl. These were 
followed by the publication of other Atlantic species by Michaux, 
Pursh and other prominent botanists. Nearly all of these early de- 
scribed species, however, were later regarded either as identical with 
S. aureus, L., or as varieties or forms of the same. By more recent 
authors certain of these earlier species have been reinstated, and 
seemingly very justly so. 
After a somewhat extended study of a representative collection of 
plants from different parts of North America, aided by a compari- 
son with the originals in the older herbaria, the writer has been led 
to the adoption of a somewhat intermediate course in the disposition 
of the species of this particular group, as well as in the treatment of 
the North American species as a whole. It is hoped that the com- 
plete results may be brought forward at an early date; but it is 
thought that a synopsis of all the forms which are at present known 
to occur in New England may be of sufficient interest to merit pub- 
lication. 
The synopsis herewith presented is based entirely upon the mac- 
'roscopic or more evident characters; and while now and then puz- 
zling forms occur, yet in the main the specific limitations are tolerably 
constant. It should, however, be borne in mind that in any group 
of plants where the foliage is subject to such variation as in this par- 
ticular group of Senecios, as complete specimens as possible should 
be obtained for satisfactory identification. The following are the 
species and varieties as now recognized for New England: 
* [ndigenous species: heads conspicuously radiate. 
Heads large, 2 cm. or more high: stems leafy throughout. 
I. PsEUDO-AnNiCA, Less. Stems 1 to 6 dm. high, more or less 
