244 COMPOSITE. (COMPOSITE FAMILY.) 



72. ERECHTHITES, Raf. FIREWEED. 

 Heads many-flowered, discoid ; the marginal flowers pistillate, very 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. ideracifolia, 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 fiat : involucre about 12-leaved, 25 - 30-jloivered. 



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 Tea- 

 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 beneath, 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. diver sifolia, Torr. & Gray. Stem angled ; leaves not glaucous, 

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



3 - 5-lobed. 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 ones 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-nerved, entire or slightly toothed ; the lowest 

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

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



