COMPOSITAE (composite FAMILY) 851 



76. ARNICA L. 



Heads many-flowered ; rays pistillate. Bracts of the bell-shaped involucre 

 lanceolate, equal, somewhat in 2 rows. Receptacle flat, fimbrillate. Achenes 

 slender or spindle-shaped ; pappus a single row of rather rigid and strongly 

 roughened-denticulate bristles. — Perennial herbs (chiefly of mountains and cold 

 northern regions), with simple stems, bearing single or corymbed large heads 

 and opposite leaves. Flowers yellow. (Name thought to be a corruption of 

 Ptarmica.) 



* Basal leaves petioled ; stem leafy. 



H- Basal leaves tapering to the petiole. 



-w. Pappus bai'bellate, bright white. 



1. A. chionopappa Fernald. Stem 0.7-8.5 dm. high, villous with flat white 

 \airs; leaves 3-5 pairs, lanceolate to narrowly ovate, mostly confined to the 

 lower half of the stem, the basal on very long slender petioles : the lower canline 

 petioled, the upper sessile and much reduced; heads 1-3, 3-4 cm. broad ; invo- 

 lucre villous, the linear- or lance-attenuate bracts 7-10 mm. long; achenes 

 3.5-5 mm. long, densely setulose ; pappus in fruit 5-6.5 mm. long. — Cold lime- 

 stone cliffs and ledges, e. Que. and n. N. B. June, July. 



■^ ++ Pappus plumose, sordid. 



2. A. m611is Hook. Stem 1.5-7 dm. high, more or less crisp-villous through- 

 out, someiohat glandular above ; leaves oblanceolate to ovate, the basal slender- 

 petioled ; the cauline (3-5 pairs) mostly sessile, 0.3-1.5 dm. long, the upper- 

 most only slightly smaller; heads 1-9, on short (3-12 cm. long) naked or 

 rarely bracted glandular-villous peduncles, 4-6 cm. broad ; involucre glandular 

 and villous, its lance-attenuate often purple-tipped bracts 1-1.6 cm. long ; achenes 

 hirsute, 4-5 mm. long, shorter than the plumose yellow-brown or olive-tinged 

 pappus. (A. Chamissonis Man., ed. 6, not Less.; A. lanceolata Nutt.) — Banks 

 of streams, e. Que. to B. C, s. to the mts. of Me. and N. H., Col., and Cal. 

 June-Aug. 



Var. petiolaris Fernald. Leaves narroic, oblanceolate, all but the very 

 uppermost tapering to slender petioles; heads 3-4 cm. broad; involucral bracts 

 scarcely 1 cm, long. — By alpine brooks. Me., N. H., and n. N. Y. 



-i- -^ Basal leaves rounded or cordate at base. 



3. A. cordifolia Hook. Stem 1.5-6 dm. high, more or less villous throughout, 

 glandular above ; basal and lower cauline leaves ovate, coarsely dentate, slender- 

 petioled. upper short-petioled or subsessile ; heads 1-8, slender-peduncled, 5-7 

 cm. broad ; involucre villous, especially at base ; bracts lanceolate to oblong, 

 acuminate, 1.3-2 cm. long ; rays about 15 ; achenes hirsute ; pappus white, 

 barbellate. — Very local, n. Mich.; Yukon to S. D,, Col., Utah, and Cal. 



* * Basal leaves rosulate, broad and sessile; stem-leaves remote and small. 



4. A. acaiilis (Walt.) BSP. Hairy and rather glandular. 1 m. or less in 

 heiglit ; leaves thickish, S-b-nerved, ovate or oblong ; heads several, corymbed, 

 showy. (A. nudicaulis Xutt.) — Damp pine barrens, Del., s. Pa., and south w. 

 Mav, June. 



77. ERECHTITES Raf. Fireweed 



Heads manj'-flowered ; the flowers all tubular and fertile ; the marginal 

 pistillate, with a slender corolla. Bracts of the cylindrical involucre in a single 

 row, linear, acute, with a few small bractlots at the base. Receptacle naked. 

 Achenes oblong, tapering at the end ; pappus copious, of very fine and white 

 soft hairs. — Erect and coarse annuals, of rank smell, with alternate simple 

 leaves, and paniculate-corymbed heads of whitish tlowers. (The ancient name 

 of some species cf Groundsel, probably called after Ererhtheus.) 



1. E. hieracifolia (L.) Raf. Often hairy; stem grooved, 0.3 to 3 m. high : 



