Pteronia.| COMPOSIT# (Harv.) 97 
Leaves linear or lin.-lanceolate, flat, not ciliate : 
Flowers yellow : 
Inv. scales softly fringed, callous ti (33) eallosa, 
Inv. scales —— , Tigid — ee glabrata. 
Flowers purple... .. --- (23) hirsuta, +. 
Lys. linear-terete, trigonous or filiform, not ciliate : 
Leaves sheathing at base, linear-filiform ... (20) flexicaulis, 
Leaves not sheathing at base: 
Lys. from 5 lines to an inch or more in length; 
Inv. scales dry, quite entire, membr. 
edged... .. ... (18) suceulenta, 
Inv. se. dry, rigid, opaque, serrato- 
lacerate ... (38) tenuifolia, 
Inv. sc. clammy, ciliolate, “‘mem- 
brane-edged, lacerate ... (13) pallens. 
Inv. sc. sub-viscid, ey silky: 
ciliate... ... (35) turbinata, 
Leaves 1—3- rarely 4- lines long : 
Twigs scabrous; heads obovoid, 
viscid, many-fl. .. (46) elongata. 
Glabrous; heads cylindrical; ‘scales 
memb. edged... (37) cylindracea. 
Glabrous, dwarf; heads. oblong-top- 
shaped; scales horny ... ... (43) empetrifolia, 
Leaves rigidly ciliate : 
Glabrous : 
Inv. scales mucronate; achenes villous (34) mucronata. 
Inv.sc.subacute; achenessparsely pilose (45) viscosa. 
Tny. sc. obtuse ; achenes —— glan- 
anlar... .. «. (48) adenocarpa. 
Twigs scabrous : 
Achenes sparsely pilose ... ... ... (46) elongata. 
Achenes quite glabrous... ... .... (47) stehelinoides. 
2. Invol. scales loosely imbricated, dry, linear, lanceolate or acuminate, often with 
wide, membranous 
Leaves alternate (at least the upper ones). 
Leaves, ae and ee ee age with minute, 
harsh points... s .. (50) seabra. 
Leaves glabrous or nearly 50: 
Achenes glabrous; leaves filiform ... ... (51) eamphorata. 
Achenes pubescent, or densely : 
Leaves pete ames crow’ fur- 
rowed beneath .. (3) baccharoides. 
Lys. lin. ~spathulate; inv. scales linear, 
tuse .. (2) glaucescens, 
Lys. linear, obtuse, pe ‘lines long : inv. 
scales acuminate... ... ... (28) leucoclada. 
Leaves oval or oblong : 
Obtuse; inv. scales broadly ovate, 
with a wide, membr. border ... (26) 
Acute ; inv. scales lin, — 
acuminate... .. (1) aspalatha. 
Lys ————* 10-12 lines. long: inv. 
lanceolate, acuminate ...... (30) acuminata. 
Leaves opposite, or pepe eres 80: 
Achenes hairy or villous : 
Iny. sc. ovate, with a wide, membranous border: 
Pappus bright red (1vs. glaucous, small, 
ovate oroblong) ... .. + (11) erythrocheta. 
Pappus pale, whitish or fulvous : 
VOL. III, 7 
