792 COMPOSITAE (COMPOSITE FAMILY^ 



tapering into winged petioles, partly sheathing at the base, sparsely serrulate ol 

 entire, the uppermost 3-8 cm. long ; racemes much crowded and appressed in 

 a dense wand-like panicle; involucre 4-6 mm. long, its bracts linear-oblong; 

 rays 6-6, small. —'Bogs and wet shores, Nfd. to Keewatin, s. to Minn., Pa., and 

 in the mts. to N. C. July-early Sept. 



20. S. specibsa Nutt. Stem stout, 0.5-2 m. high, smooth below, often 

 roughish above ; leaves thiokish, smooth, with rough margins, oval or ovate, 

 slightly serrate ; the uppermost 2-4 cm. long, oblong-lanceolate ; the lower 1.5-3 

 dm. long, 5-10 cm. wide, contracted into a margined petiole ; head^ somewhat 

 crowded in numerous erect racemes, forming an ample pyramidal or thyrsiform 

 panicle ; peduncles and pedicels rough-hairy ; involucre cylindric, often gluti- 

 nous, 4.5-6 mm. long, its firm bracts oblong; rays about 5, large. — Dry open 

 woods and thickets, local, Mass. to Minn., and southw. Sept., Oct. 



Var. angustJlta T. & G. Lower, rarely 1 m. high ; leaves lanceolate to ovate- 

 lanceolate, more nearly uniform, the lower 8-12 cm. long, 2-3 cm. wide; 

 inflorescence usually smaller. {S. rigidiuscula Porter.) — Dry open ground, 



0. to S. Dak. , and southw. Aug.-Oct. 



= = Beads paniculate, in mostly spreading or recurved-ascending secund 



clusters. 



a. Leaves fleshy ; plant maritime. 



21. S. semp^rvirens L. Smooth and stout, 0.3-2.5 m. high ; leaves entire, 

 lanceolate, slightly clasping ; the lower ones lanceolate-oblong, 1.5-6 dm. long, 

 obscurely triple-nerved ; the uppermost 4-15 cm. long ; racemes short, in an 

 open or contracted panicle ; involucre 4-6 mm. long, many-flowered ; rays showy 

 7-10. — Salt marshes, or rocks on the shore, Gulf of St. Lawrence, and southw., 

 Aug.-Nov. (rarely Dec). — Varies, in less brackish swamps, to forms with 

 thinner elongated linear-lanceolate leaves tapering to each end, and more erect 

 racemes in a more slender panicle. 



6. Leaves not fleshy ; plants not maritime. 



1. Sasal leaves long-petioled, conspicuously larger than the 10-30 (-40) remote 



or subremote cauline ones. 



o Stems strongly angled; leaves shagreen-scabrous on the upper surface ; heads 



Ib-'iO-flowered. 



22. S. pitula Muhl. Stem sharply 4:-angled, smooth, 0.5-2 m. high ; lower 

 leaves 1^ dm. long, ovate, acute, serrate, pale, very smooth and veiny under- 

 neath, but the upper surface very rough, like shagreen ; uppermost leaves lanceo- 

 late, 2-5 cm. long ; racemes rather short and numerous on the leafy-bracted 

 spreading branches ; heads rather large and full ; the involucre 3-4.5 mm. long, 

 nearly as broad, its linear-oblong bracts obtuse. — Bogs and swamps, chiefly in 

 calcareous regions, w. Me. to Ont., and southw. Aug., Sept. 



o o Stems terete or nearly so ; leaves smooth or smoothish (rarely scabrous) ; 

 heads 6-lo{-20)-flowered. 



+ Leaves mostly serrate, the lower and middle cauline (as well as the basal) 

 rather abruptly narrowed to the petiolar base. (Extreme forms of S. 

 ulmifolia might be sought here.) 



23. S. arguta Ait. Smooth; stem 6-15 dm. high, obscurely angled above; 

 leaves usually thin, sharply double-serrate ; the lower ovate or ovate-lanceolate, 

 1.5-4 dm. long, pointed at both ends, their petioles margined ; tlie upper 

 elliptical-lanceolate, 3-9 dm. long ; racemes pubescent, spreading, disposed in 

 an elongate open panicle ; involucre about 4 mm. long, its thin bracts bluntish ; 

 rays 6-7, large; achenes glabrous. — Open woods and thickets, w. Me. to Ont., 

 and southw. Aug., Sept. 



24. S. Bo6ttii Hook. Smooth, or scabrous-pubescent or below hirsute, 

 slender, often branched, 0.5-1.5 ni. high ; leaves rather finely serrate, ovate to 

 oblong-lanoexilate, pointed ; the lower 6-15 cm. long ; the upper .^raall, oblong to 

 narrowly lanceolate, often entire ; heads loosely racemose at the tips of the verj' 



