402 Compositaceae 
BLEPHARIPAPPUS (Ptilonella) 
Annual, branched, 1|—3 dm. high. Leaves alternate, narrow, linear, sessile, entire. 
Heads radiate, 6—12 mm. long (ours) ; involucre-bracts nearly in | series, almost equal; 
receptacle convex. Ray-flowers 3—6, pistillate, fertile, white, broad-cuneiform, 
3-toothed. Disk-flowers 6—12, perfect or the central ones sterile, white or purplish, 
5-toothed. Akenes turbinate, silky-villous. Pappus none or scale-like: scales 100i} 
linear or awn-like; their margins hyaline, lacerate-fimbriate so as to appear plumose. (Gk. 
blepharon—an eye-lash, Pappos—pappus. ) 
A. Plant puberulent and scabrous, with some hispid hairs above; branch-leaves not 
appressed; involucre bracts 8—1l0 mm. long; ray-corolla inrolling in sunshine. E. 
(Ptilonella scabra.) B. scaber Hook. 
AA. Plant smooth; branch-leaves appressed; involucre-bracts 4-6 mm. long; ray- 
corolla not inrolling in sunshine. E. B. laevis Gray 
MADIA TAR-WEED 
Annual, often ‘viscid or glandular. Leaves linear or lanceolate, entire or slightly 
serrate, at least the upper alternate. Heads radiate or rayless, few to many flowered; 
involucre-bracts in | series, herbaceous, keeled, much inrolled at margin, enclosing the 
ray-akenes, their tips erect or rolled in; receptacle flat or convex. Ray-flowers 0—20, 
pistillate, somewhat wedge-shaped, 3-toothed, yellow. Disk-flowers perfect, fertile or 
sterile, | to many, yellow. Akenes 4-angled to flattish, glabrous. Pappus none, or in 
M. madioides of 5—8 fimbriate-lacerate scales. (From madi, the name in Chile.) 
A. _ Disk-flowers 3 to many, their corollas pubescent; heads and ray-corollas mostly long- 
er than in AA; peduncles not long or else not filiform. 
B. Heads scattered in cymes or corymbs or panicles. 
C. Most of the leaves opposite; ray-corollas 8—20 mm. long. 
D.  Disk-akenes with pappus of 5—8 fimbriate-lacerate scales; involucre-bracts 
8—12, with short inconspicuous tps. W. (Anisocarpus madioides.) 
M. madioides Pip. 
DD. Pappus none; involucre-bracts 12—20, with long linear tips. 
E. Heads in a cyme; involucre bract with linear tip almost as long as the 
body. W. (Madaria elegans. ) M. elegans Don. 
EE. Heads in a corymb; involucre-bract with linear tip not nearly as long 
as the body. U. E. (Madaria corymbosa. ) M. corymbosa (DC.) 
CC. Most of the leaves alternate; ray-corollas 4-8 mm. long or none. 
F. Plant with lemon odor; ray-akenes wide. FE. M. citriodora Gray 
FF. Plant without lemon odor; ray-akenes not wide, but flattish. 
G. Disk-akenes 4-angled; disk- and ray-akenes prominently 1-veined on 
the faces. W.E. M. sativa Mol. (Chili Tar-weed ) 
GG. Disk-akenes flattish; neither disk- nor ray-akenes prominently veined on 
the face. W.E. (M. dissitiflora; M. racemosa.) 
M. sativa racemosa Gray 
BB. Heads congested in dense somewhat head-like clusters; pappus none ; leaves - 
mostly alternate. 
H. Ray-flowers 6—12: disk-flowers 5—12; heads 1218 mm. high, W. 
(M. capitata.) M. sativa capitate Pip. 
HH. Ray-flowers 0—5; disk flowers 3—5; heads 6—10 mm. high. 
I. Stems glandular to base; clusters of heads cymosely arranged on the plant. E. 
M. ramosa Pip. 

