filiform; the lower mostly 3-parted; heads very small, crowded in virgate
leafy panicles, tomentose, 3-4-flowered; two of the flowers pistillate and fertile;
the others staminate and sterile; receptacle slightly fimbrillate-pilose.—
Torr.! in ann. lye. N ew York, 2. p. 211. A. Plattensis, N u tt.! in trans.
Amer. phil. soc. (n. ser.) 7. p. 397.
Plains of the Platte, very abundant, D r . James ! N u t ta l l ! L ieu t. F r e mont!
July-Aug.—Plant 1-3 feet high; the branches slender and virgate.
Leaves 1-2 inches long, terete (revolute), very slender, white when young,
becoming somewhat glabrous when old.
§ 2. Rec ep ta c le n a k e d : heads homogamous ; the flow e rs a ll p e rfe c t a n d f e r tile
.— S e r iph i i j iu m , Bess.
8. A . cana (Pursh): shrubby, much branched, densely canescent throughout;
leaves linear-lanceolate, acute, flat, entire (the lowermost cuneiform
and sometimes acutely 3-lobed), equally clothed with the close silky tomen-
lum on both sides; heads obovoid-hemispherical, axillary, sessile, mostly
glomerate or spicate-paniculate, 4-6-flowered; exterior scales of the involucre
canescent; the inner scarious.—P u rsh ! fi. 2. p . 621; B e s s .! in H o o k . 1. c . ;
D C .p r o d r . 6 .p . 105. A. Columbiensis, N u tt.! g en . 2 .p . 142, Sf in trans.
A m e r. p h il . soc. (n. ser.) 7. p . 398, excluding the habitat in part.
Plains of the Upper Missouri and Platte to the Rocky Mountains, L ew is !
N u tta l l! M r . N ico lle t! L ieu t. Fremont! and plains of the Saskatchewan,
D rum m o n d !—The leaves of this well-marked species are very seldom in
any degree lobed, although there are some obscure indications in Pursh’s
specimens, collected by Lewis. We believe it has not been found west of
the Rocky Mountains; and Mr. Nuttall was mistaken in supposing it to be
the “ Wild Sage” of Lewis and Clarke’s Travels, which so abounds in the
woodless sterile plains of the interior of Oregon; so that the change of specific
name was the more unwarrantable. The name of W ild S a g e was doubtless
applied indiscriminately to several of the ensuing shrubby species, which inhabit
the region in question. But the plant given to Pursh by Lewis with
this name is the A. integrifolia, P u rsh (A. Ludoviciana, N u tt.), and was
collected on the bluffs of the Missouri, Oct. 1, 1804, upon the homeward
journey.
9. A . tr id e n ta ta (Nutt.): shrubby, much branched, densely silvery-canes-
cent; leaves crowded or fascicled, narrowly cuneiform, 3-toothed or 3-cleft at
the apex, the teeth or short lobes obtuse and approximate; those of the flower-
branchlets often linear and entire; heads obovoid, spicate-glomerate, disposed
in dense compound panicles, 5-6-flowered; exterior scales of the involucre
canescent, the inner scarious.—N u tt.! in trans. A m e r. p h il . soc. (n. ser.) 7.
p. 398. (from specimens not in flower.)
Plains of the Oregon and Lewis River (Rocky Mountains in herb.), N u tta
l l ! Wind River Chain of the Rocky Mountains, L ieu t. F rem ont! Aug.—
Shrub about a foot high, much branched. Leaves an inch or less in length,
3-4 lines wide at the apex, tapering to the base, both sides equally silvery-
tomentose; the teeth or lobes either very short, or 2-4 lines long, seldom again
toothed. Heads very numerous, smaller than in A. cana.
10. A . arbuscula (Nutt.! 1. c .): dwarf, shrubby, tomentose-canescent;
leaves short, cuneiform, 3-cleft; the lobes oblong, obtuse ; the lateral often
2-3-lobed ; heads globose-ovoid, 6-10-flowered, sessile, solitary or somewhat
clustered, forming a slender interrupted spike or spicate panicle; scales of
the involucre oval; the exterior tomentose, the inner scarious.
Arid plains of Lewis River, N u tta ll!—Shrub 4-6 inches high; the flowering
branches virgate and rather naked.
11. A. trifida (Nutt.! 1. c.) : shrubby, silky-canescent ; leaves 3-parted
towards the apex ; the segments linear, obtuse ; heads spicate, somewhat glomerate,
in a simple panicle, obovoid, 8-flowered; exterior scales of the involucre
ovate, canescent ; the inner oblong, glabrous, with scarious margins.
/?. rigida (Nutt. ! 1. c.) : leaves rigid, more silky and shining; the segments
rather acute.
Plains of the Rocky Mountains and Oregon, Nuttall!—Plant 6-8 inches
high.
§ 3. Receptacle naked (not hairy) : heads heterogamous ; the flowers all fertile.
—Abrotanum, (Tourn.) Bess.
* Perennial or shrubby.
12. A. Lindleyana (Bess.): shrubby, canescent towards the summit;
leaves nearly linear, canescently tomentose beneath; heads spicate-paniculate,
somewhat hemispherical, erect ; scales of the involucre canescent,
scarious at the apex, the outermost foliaceous ; corolla glabrous. Bess, in
Hook. 1. c., bf DC. 1. c.
a. légitima (Bess. 1. c.) : leaves entire, an inch to an inch and a half in
length.
13. brevifolia, (Bess. 1. c.) : leaves an inch long, in fascicles ; the primary
having probably fallen away.
y. suhdentata (Bess. 1. c.) : leaves linear-lanceolate, somewhat toothed at
the apex ; involucre white and tomentose.
S. Coronopus (Bess. 1. c.) : leaves pinnatifid-toothed towards the apex.—
A. pumila, Nutt. ?
“ North West Coast of America, Douglas, in herb. Lindl.", ex Besser.
Probably from the interior of Oregon__This species is unknown to us : perhaps
the following, of which we have only seen an imperfect specimen, is
one of its forms.
13. A. pumila (Nutt.) : dwarf, herbaceous, perennial, slightly tomentose-
pubescent ; leaves scattered, linear, entire, or sparingly laciniate or incised
towards the apex; heads sessile, subglobose, few, in a simple somewhat leafy
spike; scales of the involucre scarious, slightly tomentose ; the exterior ovate,
the inner broadly oval; “ flowers polygamous.”—Nutt.! in trans. Amer.
phil. soc. 1. c. p. 399.
Lewis River, in the Rocky Mountains.—Stems simple, 6-8 inches high,
from a somewhat woody base. Leaves an inch or more in length, scarcely
a line wide ; the teeth or lobes (one or two on each side) subulate. Nutt.
14. A. pedatifida (Nutt. ! 1. c.) : dwarf, suffruticose, somewhat canescent
or cinereous, cæspitose ; leaves 3-parted ; the lateral segments often 2-3-cleft,
linear, obtuse ; heads obovoid, sessile, bracteate, seldom clustered, few, in a
simple spike ; scales of the involucre ovate, pubescent, with shining scarious
margins ; corolla glabrous.
Arid plains of Lewis River, in the Rocky Mountains, Nuttall! Aug.—
“ A very distinct and peculiar species, with a stout woody root, sending out
tufts of low stems, three or four inches high, terminating in spikes of 4—10
flowers.” Nutt.
15. A. longifolia (Nutt.) : herbaceous (frequently woody at the base),
tomentose ; flowering stems simple ; leaves narrowly lanceolate-linear,
elongated, acute, entire, with revolute margins, tomentose-canescent beneath,
at length almost glabrous above ; the lower occasionally 3-5-cleft or laciniate
; the lobes linear ; heads cylindric-ovate, somewhat glomerate, sessile,
few-flowered ; involucre tomentose.—Nutt. ! gen. 2. p. 142, &ç in trans.
Amer. phil. soc. 1. c. ; not of Bess, in Hook. I. c. &çc.