COMPOSLTAE (COMPOSITE FAMILY) 871 



* * * Hpuds 5-lS-f!()wered. raremose or paniculate, commonly pendulous ; leaves 

 variable, mostly petiolate, the lower cordate or truncate or hastate at base. 



•*- Involucre cylindrical (at least below the middle); bracts scarious-margined, 



the outer numerous, short, appressed. 



** Involucre of 6-8 primai'y bracts, S-V2-floioered. 



= Pappus deep reddish-brown. 



6. P. alba L. (White Lettuce, Rattlesnake-root.) Smooth and glau- 

 cous ; stem stout, usually purplish, 0.5-1.5 in. high, corymbose-panicled at 

 summit ; leaves angulate or triaugular-halberd-form, sinuate-toothed or 3-5-cleft, 

 the uppermost oblong and undivided ; involucre whitish-green and j^urplish, 

 glaucous; flowers whitish, (yahalus Hook.) — Rich woods and thickets, s. 

 Me. to the Saskatchewan, s. to Ga., Ky., and 111. Late July-early Oct. 



= = Pappus vjhitish or brownish-white. 



a. Primary bracts scarcely as long as the pappus, the small outer ones 



lanceolate. 



7. P. serpentaria Pursh. (Lion's-foot, Gall-of-the-earth.) Stem smooth, 

 3-12 dm. high, usually purplish, corymbose-panicled at summit ; leaves thick, 



^^ variously lobed, often pinnatifid with blunt or rounded lobes, 

 or even entire, the lower on margined petioles; heads chiefly 

 clustered at the tips of elongate branches; involucre funnel- 

 form, ciilindric below, its sublierbaceous green or purplish 

 J|,: Vj^^^* frequently setnlose bracts abruptly spreading above the middle ; 

 flowers purplish, greenish-white, or cream-color ; achenes 

 1035. P. serpentaria. yellow-brown. (Xabalus Hook.) — Dry open soil, e. Mass. 

 Heads x%. to Fla. and Ala. Sept., Oct. Fig. 1035. 



b. Primary bracts as long as the pappus, the small outer ones deltoid to ovate. 



8. P. trifoliolata (Cass.) Fernakl. (Gall-of-thr-earth.) Glabrous, 1 .5-15 

 dm. high ; leaves thinnish, nearly all petioled ; the lower mostly 3-divided or 

 angulate, occasionally uncleft or with the divisions finely dis- 

 sected ; inflorescence an elongate panicle, the heads clustered 

 at the tips of comparatively short ascending branches or in the 

 upper axils; involucre cylindric, glaucous; its pale green or 

 purple-tinged primary bracts linear-lanceolate, acute, the inner 

 icith broad scarious margins; outer calycidate bracts lance- 

 deltoid, rather fiiTu, with pale hyaline margins, regularly 1036. P. trifoliolata. 

 imbricated, the longest 1.5-2.5 mm. long; achenes yellow- Heads x%. 

 brown. {Nabalus Cass.; P. serpentaria Man. ed. 6, in part, 



not Pursh.) — Thickets and woods, Nfd. and Que. to Del., Pa., and along the 

 mts. to Tenn. Aug., Sept. Fig. 1036. 



9. P. nana (Bigel.) Torr. Stem simple and strict, 0.5-7.5 dm. high ; leaves 

 much as in the preceding, very variable in outline; inflorescence a thyrse or 

 raceme, rarely somewhat paniculate or subcorymbose ; involucre thick-cylindric, 

 glabrous ; bracts lead-color or blackish ; the primary ones linear- to lance-oblong, 

 blunt or acutish, the inner with narrow scarious margins; outer calycidate 

 bracts ovate to ovate-lanceolate, blackish-green, herbaceous or fleshy, very 

 unequal, the longest 3-6 mm. long; achenes yellowish- to reddish-brown. 

 (Nahalns DC; JP. serpentaria, var. Gray; P. trifoliolata, var. Fernald.) — 

 Rocky or mossy places, Lab. and Nfd. to the coast of N. S., and the higher mts. 

 of n. N. E. and n. N. Y. July-Sept. 



■^ -^ Involucre of 5 primary bracts, 6-6-floicered. 



10. P. altissima L. Smooth, tall and slender, 1-2 m. high ; heads in small 

 axillary and terminal loose clusters forming a long and wand-like leafy panicle; 

 leaves membranaceous, all petioled, ovate, heart-shaped, or triangular, and 

 merely toothed or cleft, with naked or winged petioles, or frequently 3-5-parted, 



