276 COMPOSITE, (composite family.) 



49. RUDBECKIA, L. CoyE-FLowER. 



Heads many-flowered, radiate; the rays neutral. Scales of the involucre 

 leaf-like, in about 2 rows, spreading. Receptacle conical or columnar; the 

 short chaff concave, not rigid. Achenes 4-augular (in our species), smooth, 

 not margined, flat at the top, with no pappus, or a minute crown-like border. 

 — Chiefly perennial herbs, witli alternate leaves, and showy terminal heads ; 

 the rays generally long, yellow, often darker at base. (Named in honor of 

 the Professors Rudbeck, father and son, predecessors of Linnaeus at Upsal.) 



* Dish columnar in fruit, dull greenish-yellow ; leaves divided and cut. 



1 . R. laciniata, L. Stem smooth, branching (2 - 7° high) ; leaves smooth 

 or roughish, the lowest pinnate, with 5-7 cut or 3-lobed leaflets ; upper leaves 

 irregularly 3-5-parted, the lobes ovate-lanceolate, pointed, or the uppermost 

 undivided; heads long-peduncled ; disk at first globular or hemispherical; 

 chaff truncate, downy at the tip; rays oblanceolate (1 -2' long), drooping. — 

 LoAv thickets ; common. July - Sept. — Var. humilis, Gray, low and glabrous, 

 some of the radical leaves undivided or with roundish divisions; heads smaller 

 (i' high) and ray shorter. Mountains of Va. and southward. 



* * Disk hemispherical to oblong-ovoid in fruit, dark purple or brown. 



•t- Lower leaves 3-lobed or parted. 



2. R. triloba, L. Hairy, biennial, much branched (2-5° high), the 

 branches slender and spreading; upper leaves ovate-lanceolate, sparingly 

 toothed, the lower 3-lobed, tapering at the base, coarsely -serrate (those from 

 the root pinnately parted or undivided) ; rays 8, oval or oblong ; chaff of the 

 black-purple depressed-globular disk smooth, awned. — Dry soil, Penn. to 

 Mich., Mo., and southward. Aug. — Heads small, but numerous and showy. 



3. R. subtomentosa, Pursh. Stem branching above (3-4° high), 

 downy, as well as the petiolate ovate or ovate-lanceolate serrate leaves beneath ; 

 heads short-peduncled ; disk globular, dull brown ; receptacle sweet-scented ; 

 chaff downy at the blunt apex. — Prairies, Wise, 111., Mo., and southward- 



■*- -t- Leaves undivided, rarely laciniately toothed. 



4. R. hirta, L. 5^'e?jn/a/, very rough and bristly -hairy throughout; stems 

 simple or branched near the base, stout (1-2° high), naked above, bearing 

 single large heads ; leaves nearly entire ; the upper oblong or lanceolate, sessile ; 

 the lower spatulate, triple-nerved, petioled ; rays (about 14) more or less ex- 

 ceeding the involucre; chajf (fthe dull brown disk hairy at the tip, acutish. — 

 Dry soil, western X. Y. to Wise, and southward. Now common as a weed 

 in eastern meadows, introduced with clover-seed from the West. June- 

 Aug. 



5. R. fiilgida, Ait. Hairy, the branches naked at the summit and bear- 

 ing single heads ; leaves spatulate-oblong or lanceolate, partly clasping, triple- 

 nerved, the upper entire, mostly obtuse; rays about 12, equalling or exceeding 

 the ample involucre; chaff of the dark purple disk nearly smooth and blunt. — 

 Dry soil, N. J. and Penn. to Ky., Mo., and southward. — Variable, 1-3° high ; 

 the rays orange-yellow. 



6. R. spathulata, Michx. Pubescence short and appressed ; slender, 

 8' -3° high; leaves obovate or spatulate or the upper ovate to lanceolate, 



