172 
none, sometimes truncate, more commonly acuminate or aristate at tip: mostly low 
herbs. 
== = Involucre spreading or soon retlexed., 
90. Helenium. livolucral bracts subulate or linear: rays fertile or sterile, rarely 
none: disk-corollas with short or almost obsolete tube, the teeth of the limb obtuse 
and glandular-pubescent: pappus of 5 or 6 thin scarious scales: leaves commonly 
impressed-punctate, mostly decurrent. 
91. Amblyolepis. Principal involucral bracts foliaceous and lanceolate; an inner 
hyaline serics resembling the conspicuous blunt nerveless scales of the pappus: rays 
fertile, ample: disk-corollas glabrous throughout, with a distinct tube as long as 
the ampliate throat, the lobes attennate-acute: leaves neither punctate nor decur- 
rent. 
++ ++ Receptacle beset with setiform or subulate fimbrille among the flowers. 
92. Gaillardia. Involucre broad, largely foliaceous and lax: ray-flowers neutral, 
sometimes none: lobes of disk-corollas beset with jointed hairs: pappus conspicu- 
ous, longer than the achene, of 5 to 10 hyaline scarious awned scales, 
***** Tnvoluere of the small heads composed of a few equal connivent bracts in a 
single series: ligules small: achenes terete, oblong or linear, 8 to 10 
striate-costate: leaves opposite: no oil-glands. 
93. Sartwellia. Heads with about 5 ligulate female and rather numerous perfect 
tubular flowers: disk-corollas 4 or 5-toothed: involucral bracts 5: pappus a deep 
cupule with fimbriolate edge, or of 4 or 5 narrowly oblong fimbriolate-truncate scales 
alternating with as many awns. 
94. Flaveria. Heads 1 to several-flowered, the flowers all fertile and tubular, or 
one femaie and short-ligulate: disk-corollas 5-toothed: involueral bracts 2 to 5: 
pappus none, or rarely of 2 to 4 thin scales. ’ 
****** Tnvolucre a series of equal bracts, either distinct or united into a cup or 
tube, dotted or striped with oil-glands: rays when present fertile: 
achenes mostly narrow and striate: herbage like the involucre commonly 
dotted with some oil-glands. 
+ Style-branches of perfect flowers more or less elongated, appendiculate or truncate. 
= Pappus simple, of copious capillary scabrous bristles: receptacle naked and smooth; 
involucral bracts distinct. 
95. Porophyllum. Ray-flowers none; involucral bracts 5 to 10: achenes slender. 
96. Chrysactinia. Ray-flowers conspicuous: involucral bracts 10 or more: 
achenes short-linear, not attenuate upward: flowers all yellow. 
= = Pappus double, of distinct bristles and scales: receptacle naked: involucral 
bracts distinct. 
97. Nicolletia. Involucre oblong or cylindraceous: achenes filiform-linear, with 
tapering base: pappus double, outer of numerous capillary bristles, inner of5 lanceo- 
late long hyaline awned scales. 
= = = Pappus either wholly of scales, or some or all of the scales bearing or 
largely resolved into awns or capillary bristles: receptacle variously fimbrillate, 
dentate, or naked: involucral bracts united or sometimes distinct. 
98. Dysodia. Proper bracts of the involucre generally united at base, rarely quite 
separate, rarely united to near the summit: pappus a row of chafty scales dissected 
into as many bristles. 
99. Hymenatherum. Involucre cupulately gamophyllous high up: pappus of 
chaffy scales, either awned or pointed, or partly resolved into bristles, or some or all 
of them entire and even truneate. 
+ + Style-branches of perfect flowers very short, obtuse and inappendiculate. 
100. Pectis. Heads radiate: involucre of few or several equal keeled bracts in a 
