244 coMPOsiT.E. (composite family.) 



72. ERECHTHITES, Raf. Fireweed. 

 Heads many-flowered, discoid ; the marginal flowers pistillate, veiy slender, 

 2-3-toothed ; the others perfect, 4 - 5-toothed. Scales of the cylindrical involu- 

 cre in a single row, linear, acute, bracted. Receptacle naked. Achenia oblong, 

 striate. Pappus of copious soft hairs. — Erect annual herbs, with alternate 

 simple leaves, and corymbose heads of. greenish flowers. 



1. E. hieracifolia, Raf Stem mostly branched, smooth or hairy ; leaves 

 lanceolate, sessile, sharply serrate or toothed ; the upper somewhat clasping ; 

 bracts subulate, minute ; pappus white. (Senecio hieracifolius, L) — Rich soil, 

 common. July - Sept. — Stem 1° - 5° high. 



73. CACALIA, L. 



Heads 5 - many-flowered ; the flowers all tubular and perfect, 5-cleft. Scales 

 of the involucre 5-30, in a single row. Receptacle flat, naked, or with a tuber- . 

 cular prominence in the centre. Achenia oblong, smooth. Pappus of numerous 

 capillary bristles. — Perennial, mostly smooth and tall herbs, with alternate 

 entire or lobed leaves, and corymbose heads of white flowers. 



* Receptacle flat : involucre about 12-leuved, 25 -30 flowered. 



1. C. suaveolens, L. Smooth ; leaves ovate, hastate, acute, toothed- 

 serrate, on winged petioles; the uppermost sessile; bracts filiform. — Low 

 ground, West Florida, and northward. Sept. and Oct. — Stem 3° - 5° high. 



* * Receptacle tubercular in the centre : scales of the involucre and flowers 5. 



2. C. reniformis, Muhl. Stem angled ; leaves not glaucous, angularly 

 toothed, on slender petioles ; the lowest large, reniform, the upper ones roundish ; 

 corymb compound. — Damp soil in the mountains of North Carolina and Teur 

 nessee. July and Aug. — Stem 4° -9° high. Radical leaves sometimes 2° 

 in diameter, the teeth mucronate. 



3. C. atriplicifolia, L. Stem terete, corymbosely branched above ; 

 leaves glaucous benealli, angularly lobed, the lobes mostly entire, mucronate ; 

 the lowest ones reniform ; the upper rhomboid ; corymbs compound. — Woods 

 and moist banks, Florida, and northward. — Aug. and Sept. — Stem 4° - 8° high. 

 Leaves smaller and thicker than the last. 



4. C. diversifolia, Torr. & Gray. Stem angled ; leaves not glaucous, 

 petioled ; the lowest broadly cordate or cordate-ovate, obtusely toothed, the upper 

 3 - 5-Iobed. — Muddy banks of the Chipola River, Marianna, West Florida. 



.May - Aug. — Stem 2° -3° high. 



5. C. ovata, Walt. Stem terete; leaves glaucous beneath, 3-5-nerved, 

 ovate or oval, obtuse, entire or wavy-toothed ; the lowest long-petioled ; the 

 upper on«6 sessile ; corymbs open. — Swamps, Georgia, Florida, and westward. 

 July and Aug. — Stem 3° - 4° high. Lowest leaves .5' - 8' long. 



6. C. tuberosa, Nutt. Stem furrowed, angled ; leaves not glaucous, oval 

 or lanceolate-oblong, strongly .5 - 7-ncrved, entire or slightly toothed ; the lowest 

 long-petioled ; corymbs dense. — Swamps, Georgia, Florida, and westward. 

 Aug. and Sept. — Stem 3° - 5° high. Leaves thick. 



