COMPOSITiE. (composite FAMILY.) 251 



■*-*■ ■*-*■ Leaves more or less plainly 3-rihbed ; heads in one-sided spreading or re- 

 curved racemes, forming an ample panicle. Not maritime. 

 = Smooth and glabrous, at least the stem and bright qrem leaves, 

 a. Leaves Jirm and rather rigid ; involucral scales thirkish, obtuse, r/uite unequal. 



29. S. Missouriensis, Nutt. Smooth througliout (l-. 3° hi^rh); leaves 

 linear-lanrcolali', or tlie lower broadly lanceolate, tapering tc. both ends, with 

 'ery rough margins; teeth, if any, sharp and rigid ; heads and dense crowded 

 racemes nearly as in u. 28 ; achenes nearly glabrous. — Dry ])rairies, from Wise, 

 and Ind. soutli and westward. — Heads 1^-2" long. 



30. S. Shortii, Torr. & Gray. IStem slender, simple (2-4° high), mi- 

 nutely rougliish-pubcscent above; leaves (the larger 2-3' long) oblong-iance- 

 olate, acute, tlie lower mostly serrate with a few fine teeth ; racemes mostly 

 short in a crowded panicle ; achenes silk-g-pubescent. — Rocks at the Falls of 

 the Ohio; Ark. — A handsome species; heads 3" long, narrow. 



b. Leaves thinner ; involucral scales thin, chiejijj linear, obtuse. 



31. S. serotina, Ait. Stem stout (2-7° high), smooth, often glaucous; 

 leaves quite smooth both sides, lanceolate, taper-pointed, very sharply serrate, 

 except tlie narrowed base, rough-ciliate ; the ample panicle pubescent ; rai/s 

 7 -\4, rather long. (S. gigantea, of previous ed.) — Copses and fence-rows; 

 common, and presenting many varieties. Seldom very tall. 



A'ar. gigantea, Gray. Commonly tall, 5-8° high; leaves more or less 

 pubescent or hispidulous beneath. (S. gigantea, Ait.; S. serotina of previous 

 ed.) — Thickets and low grounds, Can. to Tex. 



32. S. rupestris, Kaf. Stem smooth, slender, 2-3° high; leaves linear- 

 lanceolate, tapering both ways, entire or nearly so ; panicle narrow ; heads very 

 small ; rays 4-6, very short. — Rocky river-banks, W. Va. to Ky. and Ind. 



= = Pubescent {at least the stem) or hispidulous-scabrous. 



33. S. Canadensis, L. Stem rough-hairy, t^W and stout (3 - 6° high) ; 

 leaves lanceolate, pointed, sharply serrate (sometimes almost entire), more or 

 less pubescent beneath aud rough above ; heads small ; rays very short. — Borders 

 of thickets and fields; very common. — Varies greatly in the roughness and 

 hairiness of the stem and leaves, the latter oblong-lanceolate or elongated 

 linear-lanceolate; — in var. pr6ckra, whitish-woolly underneath; and in var. 

 scXbra also very rough above, often entire, and rugose-veined. 



34. S. nemoralis, Ait. Clothed rrith a minute and close grayish-hoary 

 (soft or roughisli) pubescence ; stem simple or corymbed at the summit (^-2^° 

 high) ; leaves oblanceolate or spatulate-oblong, the lower somewhat crenate- 

 toothed and tapering into a petiole; racemes numerous, dense, at length re- 

 curved, forming a large and crowded compound raceme or jianicle whicli is 

 usually turned to one side; scales of the involucre linear-oblong. a])pressod ; 

 rays 5-9. — Dry sterile fields; very common. Flowers very bright yellow, 

 beginning early in Aug. — Var. incana, Gray, of Minn., and westward, is a 

 dwarf form, with rigid oval or oblong leaves, rather strongly serrate or entire, 

 and the clusters of heads in a dense oblong or conical thyrse. 



35. S. r^dula, Nutt. Stem and oblong or obovate-spatulate leaves rigid 

 and very rough, not hoary, the upper sessile; scales oblong, rigid; rays 3-6; 

 otherwise nearly as in n. 34. — Dry hills, W. Ill,, Minn., Kan., and s<Hithward. 



