Grassy plains of the Platte, Nuttall.—Scape 1-2 feet high, 2-4 times dichotomous.
Heads fastigiate, resembling those of C. biennis ; from which this
species is distinguished by its mostly naked and slightly pubescent scape,
narrower and less scarious scales of the involucre, &c., as well as the much
more entire leaves. Some states seem to approach the following species, so
as only to be distinguished by the larger heads, and more or less pubescent
involucre.
2. C. glauca: perennial, glabrous and glaucous throughout; leaves all
radical, thickish, spatulate-oblong, or nearly lanceolate, mucronate or somewhat
acuminate, tapering to the base, unequally runcinate-toothed or runci-
nate-pinnatifid, or some of the leaves entire; scape naked, twice or thrice
dichotomous, with minute bracts at the divisions; scales of the proper involucre
about 12, linear; the calyculate scales minute; achenia obscurely
angled, smooth, slightly attenuated towards the apex, as long as the pappus.
—Crepidium glaucum, Nutt. ! in trans. Amer. phil. soc. 1. c.
0. caulescens: not glaucous [?] ; stem with a cauline leaf at the first
division.—Crepidium caulescens, Nutt. 1. c.
Plains of the Upper Platte, Nuttall! Lieut. Fremont! July-Aug.—
Scapes about a foot high. Heads much smaller than in C. runcinata, about
30-flowered. Leaves 3-6 inches long, tapering into an indistinct or winged
petiole. Achenia strongly striate-ribbed, smooth.
3. C. occidentalis (Nutt.): perennial ? dwarf, canescent with a close fur-
furaceous pubescence; cauline leaves few, sessile, pinnately parted, with the
linear or lanceolate lobes often somewhat toothed; the radical lanceolate,
acute, runcinate-pinnatifid, tapering into a petiole ; the short lobes toothed ;
heads (few) paniculate-corymbose; proper scales of the cylindrical involucre
8- 10, linear-lanceolate, canescent, and sparsely hispid with blackish hairs
intermixed ; the calyculate scales few and very short; achenia fusiform, not
angled or striate, as long as the pappus.—Nutt. ! in jour. acad. Philad. 7.
p. 29. Psilochaena occidentalis, Nutt. ! in trans. Amer. phil. soc. 1. c.
On the Oregon, near the Rocky Mountains, Mr. Wyeth ! Plains of the
Platte, Nuttall!—A span high. Heads as large as in C. runcinata, about
20-flowered. Achenia probably all fertile, tapering to the apex, not rostrate.
Pappus grayish-white.
§ 2. Involucre few-flowered, cylindrical; the exterior calyculate scales very
short and oppressed: receptacle naked: achenia slender, 5-10-striate.—
P hjECAsium, Cass., Reichenb. (Crepis § Leptotheca, Nutt.}
4. C. nana (Richards.): perennial, nearly acaulescent, depressed, very
glabrous and glaucous; scapes numerous from the summit of the somewhat
fusiform caudex, clustered, bearing one or more about 14-flowered heads,
scarcely equalling the elliptical or roundish entire or sinuate-lyrate long-
petioled leaves; achenia linear, narrowed at the apex, scarcely rostrate.—
Richards.! appx. Frankl. journ. ed. 2. p. 92 ; Hook. ! appx. Parry's 2nd
voy. p . 397, t. 1, w fi- Bor.--Am. 1. p. 297. Hieracium, &c., Gmel.jl.
Sibir. 2. p. 20, t. 7, ƒ. 2 ^ -3 . Prenanthes pygmaea, Ledeb. in mem. acad.
St. Petersb. 5. p . 553. P. polymorpha, Ledeb. ! fi. Alt. 4. p. 144. (a. Sf /3.)
Barkhausia nana, DC.! prodr. 7. p. 156.
From the Arctic coast and islands ! to lat 64°, and on the northern Rocky
Mountains! (Also in Arctic Siberia!)—Scapes and leaves an inch or two in
height; the lamina of the inner leaves often oblong-linear. Corolla yellow,
turning purplish in drying. Achenia all uniform, or the central perhaps a
little longer than the marginal, 10-striate, a little constricted at the apex, and
then dilated into a disk that bears the pappus ; certainly none of them rostrate
as in BaTkhausia !
5. C. elegans (Hook.): perennial, very glabrous and glaucous; stems
numerous from the same fusiform root, slender, paniculate, bearing numerous
(small) 10-14-flowered heads ; radical leaves oval or spatulate, petioled,
nearly or quite entire; the cauline narrowly spatulate ; the upper linear, sessile.—
Hook. ! fi. Bor.-Am. 1. p. 297 ; DC. ! prodr. 7. p. 172. Barkhausia
elegans, Nutt, in trans. Amer. phil. soc. 1. c. p. 435.
On the Assiniboin River, Drummond!—Plant 6 inches high ; with rather
smaller heads than the preceding; the young achenia similar to those of that
species, and not more rostrate.
6. C. acuminata (Nutt.): perennial; stem nearly glabrous, sparingly
leafy, bearing numerous 8- 10-flowered heads in a naked and fastigiate compound
corymb ; leaves pubescent, lanceolate ; the radical runcinate-
pinnatifid, tapering at the base into a petiole, and at the apex into a slender
entire acumination ; the cauline few and sessile ; the uppermost narrowly
linear, entire ; calyculate involucral scales villous-pubescent when young.—
Nutt. ! in trans. Amer. phil. soc. 1. c. p. 437.
Plains of the Platte, Nuttall!—Root long and fusiform. Scapiform stem
a foot high. Radical leaves 4-5 inches long. Heads more slender than in
C. nana; the young achenia, pappus, &c. similar.
193. TROXIMON. Nutt. inFras. cat. 1813, Sf gen. 2. p. 127 ; not of Gcertn.
Agoseris, Raf. (excl. char.)—Ammogeton, Schrad.
Head many-flowered. Scales of the campanulate involucre ovate-lanceolate,
acute or acuminate (distinct or nearly so), membranaceous, somewhat
loosely imbricated in 2-3 series ; the exterior sometimes shorter. Receptacle
subalveolate, rarely with a few chaffy scales intermixed among the
flowers! Achenia glabrous, oblong-linear, somewhat obcompressed, 10-
ribbed, with a large basilar callus, more or less narrowed at the apex, but
scarcely if at all rostrate. Pappus longer than the achenium, consisting
of copious and unequal rather rigid white bristles, in several series, scarcely
scabrous, the stronger ones gradually thickened towards the base, and frequently
more or less flattened.—Perennial acaulescent herbs, with the aspect
of Scorzonera (natives of the Upper Mississippi and Missouri, the interior of
Oregon, Saskatchawan, &c.,); the naked simple scapes terminated by a large
head. Root fusiform or thickened. Leaves linear or lanceolate, elongated,
entire, denticulate, or rarely runcinate-pinnatifid. Flowers showy, yellow,
sometimes changing to purple or rose-color when old or in drying.
We find a gradual transition from the typical species of Troximon to Macrorhyn-
chus, to which genus this bears nearly the same relation that Crepis does to Barkhausia.
Even the nature of the pappus fails to furnish a very marked distinction,
although in Troximon it is more or less rigid. Indeed, were the genus founded on
T . cuspidatum alone, it would inevitably be referred to the subtribe Scorzonereae;
for all the bristles of the pappus in that species are somewhat flattened and wider
towards the base ; the inner and stronger ones so much so that they should rather
be termed palece than bristles. But this character is much less evident in the nearly
allied T. glaucum; and in the other species the bristles are capillary, although rather
stiff. The remaining Troximon of Gaertner proving a Scorzonera, the name should
certainly be kept for the present genus.
1 . T. cuspidatum (Pursh): somewhat tomentulose when young; leaves
narrowly linear-lanceolate, attenuate-acuminate, somewhat nerved, especially
vol. i i— 62