406 Compositaceae 
A. Rays |—3 mm. long. U. E. stachadifolium Lag. 
AA. Rays 10—20 mm. long. 
B. Akenes glabrou. W.C.E. (E caespitosum; E achillaeoides; E. peduncula- 
tum. ) E. lanatum Forbes 
BB. Akenes glandular. U. C. E. (E. gracile; E. integrifolium; E. lanceolatum.) 
E. multiflorum Rydb. 
RIGIOPAPPUS 
Annual, small, slender. Leaves opposite. Heads small, inconspicuously radiate, 
terminal, many-flowered; involucre-bracts many, narrowly linear, herbaceous, involute; 
receptacle flat. Ray-flowers 5—15, yellow but in age often becoming purplish or whitish, 
entire or 2-toothed, not exceeding the disk-flowers. Disk-flowers 3—5-toothed, yellow. 
Pappus 0—5 scale-like (naked) awns. (Gk. rigios—stiff, pappos—pappus.) E. 
R. leptocladus Gray 
CHAENACTIS 
Leaves alternate, entire to pinnately dissected. Heads rayless but the marginal 
flowers usually larger, solitary or cymose or corymbose, many-flowered; involucre-bracts 
linear, erect, equal, herbaceous; receptacle flat. Corolla short-toothed, yellow or white 
or flesh-color, marginal ones sometimes approaching rays. Akenes slender, pubescent. 
Pappus none or of veinless hyaline scales. (Gk. chainein=to yawn, aktis—=a ray; refer- 
ring to the dilated marginal corollas. ) 
A. Heads corymbose or cymose. 
B. Corollas yellow; plant merely puberulent. E. 
C. nevii Gray 
BB.  Corollas white or flesh-color; plant somewhat floccose-woolly. 
C. Leaves all entire; corollas white: papus of 10 scales. FE. 
C. cusickii Gray 
CC. Leaves 1|—2-pinnatifid. 
D. Pappus of 8—12 scales; corollas flesh-colored. E. (C. douglasii achillaet- 
folia.) C. douglasii H. & A. 
DD. Pappus of 4—5 scales: corollas white. E. 
C. steviodies H. & A. 
AA. Heads solitary; alpine; corollas flesh-colored. C. E. (C. alpina; C. douglasii 
aipira. ) C. nevadensis Gray 
BAHIA. 
Leaves in ours opposite, except above, palmately 2—5-parted. Heads rayless or 
radiate, terminal, small or medium, many-flowered: involucre-bracts herbaceous, in 12 
series, woolly; receptacle flat. Ray-flowers from none to conspicuous, yellow, in ours 
5—6, oval, hardly exceeding the disk-flowers. Disk-flowers yellow. Akenes narrow, 
4-angled. Pappus in ours of 4—8 scales. (Honor of J. F. Bahi, a Spanish botanist. ) 
EF. B, oppositifolia Nutt. 
HULSEA 
Viscid-pubescent, balsam-scented. Leaves alternate; in ours mostly basal, the lower 
incised to pinnatifid. Head | (ours), radiate, large, many-flowered; involucre-bracts thin, 
herbaceous, in 2—3 series; receptacle flat. Ray-flowers many, yellow. Disk-flowers 
yellow. Akenes linear-cuneate, flattish or somewhat 4-angled, soft-villous. Pappus of 4 
lacerate hyaline scales. E. (Honor of G. W. Hulse, a U. S. army surgeon. ) 
H, nana Gray 

