ASTER ARDENS 235 
— Rich rocky woods, filling cleared or half-open spaces, form- 
ing dense tangles ; reaching greatest development when growing 
more separately out of deep rich rock crevices; near N. Y. City, 
on gneissic rocks, at its prime Se. 15, two weeks earlier than 
most A. divaricatus plants close by ; and often forming circles 
around rocks and stumps. Examples : 
N. Y. , Inwood, Se. 27,’97; Yonkers, cip Mawr Park, summit rocks 
and Split ege Se 26, '96, Se. 25, '97, Se. 14 and 17, ’98, Se. 16, ’99, Se. 15, 1900. 
Se. I4, 1903, Se. '04, ras with late plants Oc. 26, '98, Nov. 3, '96, etc. ; develop- 
ment, IÓ in. high o n July 13, with 12 leaves, besides half as many already gone. ions 
** Bryn Mawr Park, woods, high rocky spot, Se. 4,'98," Bz.,as “A. Claytoni var. ?? 
, 98, Bi. ; Glen i woods, Se. 20, '98, 47. ; Cheilanthes rock, Ge: 
16, ’98, Bz. Hillview swamp, I5, 97, in drier rocky spots and thicket-covered 
ad banks along ditches; so i P '98, Se. '99, Se. 22, 1900; then destroyed by 
clearing. 
Allies. From A. divaricatus, A. ardensis in part distinguished 
by its pinnated floriferous inflorescence, its leaves, which if simi- 
larly strong in sinus are short, if similarly long are scutiform and 
brace-based, if winged are apt to have the wing semi-circular and 
margins slit-serrate. Its broad rounded bracts, red stem, and little 
pinched-urn heads, are other differences. 
From A. Zstriformis, with which it grows, A. ardens is dis- 
tinguished by absence of listriform leaves, by stronger coarser 
texture and habit, brighter red stem, less red in rays and disks, etc. 
Compared with A. C/aytoni; both have warm glowing golden 
disks, but in A. C/aytoni they develop little red, and turn sienna- 
brown ; in A. ardens the sienna is soon developed into red or crim- 
son. Both show red on the stem, strengthened sometimes into 
ebony ; in A. C/aytoni dull, in A. ardens very bright during growth, 
and of a more purplish cast ; in the similarly dark A. ebeneus there 
is less red, more brown or black. All three species have a pin- 
nated inflorescence branching deeply down the stem, each branch 
somewhat radiately and briefly divided at its summit in A. Clay- 
toni, corymbosely and very loosely compound in A. ardens, very 
densely in A. ebeneus. All may be smoothish to touch during 
growth ; A. ebeneus is much rougher when dry than A. Clayton 
and that more than A. ardens. 
Another congener, A. sti/ettiformis, is suggested by the slit- 
serrate upper axiles of A. ardens and by its broad bracts. The 
two grow together, and perhaps pass into each other—as what 
