LAYIA COMPOSITZ $51 
ACHYRACH ENA : 
lar, perfect. Bracts.of the involucre equal, in a single series, the 
base convolute and enclosing the ray-achene, foliaceous above, 
Receptacle flat, pubescent, with a row of chaffy scales between the 
ray- and disk-flowers, Style-branches of the disk-flowers filiform, 
very acute, hairy above, at length exserted and recurved. Achenes 
of the ray glabrous, linear-oblong, more or less obcompressed, 
somewhat incurved, crowned with a small protuberant areola, des- 
titute of pappus: of the disk linear-clavate, angled, appressed- 
pubescent or villous, with a pappus of 10-20 equal bristly or 
subulate awns which are naked and scabrous-serrulate above 
and plumose or villous with long weak hairs toward the base. 
L. glandulosa H. & A. 1. c. 358. Stems 4-12 inches high, diffusely 
branched, hispid or hirsute and with dark stipitate glands above: leaves 
linear-lanceolate, 1-2 inches long, the lower ones often more or less pinnati- 
fid: heads solitary at the end of the branches, campanulate, 6 lines high ; 
its bracts linear-oblong: rays 8-14, bright white, 6-8 lines long, 3-lobed: 
chaff of the receptacle lanceolate, equalling or exceeding the disk-flowers: 
pappus 10-20 stout bristles, copiouly villous. Sandy-banks and barren 
grounds, Brit. Columbia to California and Idaho, east of the Cascade Mts. 
L. Douglasii H..& A.1.c. ‘“‘ Low, sparsely hirsute or hispid, a few 
small stipitate glands on the upper leaves and involucre: radical leaves pin- 
natifid-dentate; upper, linear and entire: rays rather short, broad, 3-cleft ; 
lobes of disk-corola hirsute outside: akenes narrow, those of the disk vill- 
ous-pubescent: pappus of about 10 minutely scabrous linear-subulate flat 
palez, nearly equalling disk-corollas; their margins toward the base scan- 
tily beset with long and straight villous hairs. Gravelly banks, between 
the Dalles and Great Falls of the Colnmbia River, Douglas. ” 
57 ACHYRACHENA Schauer. Del. Sem. Hort. Vratsil 1838. 
A low annual with chiefly alternate leaves and middlesized 
heads of yellow flowers terminating the branches. Heads many- 
flowered ; the ray-flowers 6-10, with 3-cleft ligule much shorter 
than its filiform tube, little surpassing the disk; disk-corollas 
slender, 5-toothed. Involucre oblong-campanulate, of lanceolate 
‘thin-herbaceous bracts: chaff of the receptacle similar but thin- 
ner, only between the disk- and ray-flowers, distinct. Achenes 
all clavate, with attenuate base, symmetrical, 10-costate ; those of 
theray slightly obcompressed, rounded at apex and with slightly 
protuberant areola; those of the disk mostly fertile, the truncate 
apex bearing a large pappus of 10 elongated-oblong obtuse silvery- 
scarious pales, the 5 inner as long as the corolla and achene, the 
alternate outer ones shorter. 
A. mollis Shaurer |. c. Villous-pubescent and slightly glandular-viscid : 
stems erect, 6-18 incbes high branching: leaves alternate, or the lowest 
opposite, narrowly linear, 2-4 inches long, sessile, entire, or the lower la- 
ciniate: heads solitary, long-peduncled, terminating the stem and fastigiate 
branches, an inch or less long: pappus 8 lines long, in fruit when dry 
spreading and forming a globular silvery-chaffy head. In fields and open 
places, southern Oregon and western California. 
Tribev HELENIOIDE B. & H. Gen. ti, 167. Heads hete- 
rogamous and the ligulaie ray-flowers mostly fertile, or homogamous; 
