252 COMPOSITA. (COMPOSITE FAMILY.) 
ribbed or angled, muricate on the ribs ; the apex abruptly produced into a long 
beak. Pappus of copious white hairs. — Stemless perennial herbs. Scapes hol- 
low, bearing a single head of yellow flowers. Leaves all radical, oblong or 
lanceolate, entire or pinnatifid. ts $ 
1. T. Dens-leonis, Desf. Leaves pinnatifid, the lobes acute, toothed; 
heads showy. — Damp soil, sparingly naturalized. 
*. 
88. PYRRHOPAPPUS, DC. 
Heads many-flowered. Involucre double, of numerous subulate scales ; the 
inner ones erect and partially united, often with a callous appendage at the apex. : 
Receptacle flat, naked. Achenia oblong, nearly terete, 5-furrowed ; the un 
narrowed into a long filiform beak. Pappus of copious soft reddish or brownish 
hairs. — Smooth annual herbs. Leaves oblong or lanceolate, commonly toothed 
or pinnatifid. Heads solitary, terminating the naked stem or pedunclelike 
branches. Flowers yellow. 
d 
1. P. Carolinianus, DC. Stem branching ; leaves lanceolate, mostly 
toothed or pinnatifid ; achenia shorter than the filiform beak. (Borkhausia, 
Ell.) — Fields, Florida to Mississippi, and northward. April - July.— Stem 
19 - 2° high. | 
89. LACTUCA, L. LETTUCE. 
Heads few- or many-flowered. Scales of the cylindrical involucre imbricated ; 
the outer ones short. Receptacle naked. Achenia compressed parallel pde 
scales, smooth, abruptly narrowed into a filiform beak. Pappus of copious 
white hairs.— Tall herbs, with entire or pinnatifid leaves. Heads paniculate. 
Flowers white, purple, blue, or yellow. 
1. L. elongata, Muhl. Smooth or nearly so; stem tall (49— 89), simple 
or paniculate; leaves elongated, lanceolate, sessile or partly clasping ; the upper 
ones mostly entire; the lower pinnatifid ; panicle long, leafless ; flowers yellow. 
— Var. InTEGRIFOLIA. Leaves all undivided, or the lowest pinnatifid ; flower 
yellow or purplish. — Var. GRAMINIFOLIA. Smaller (2°- 39), leaves linear wv 
linear-lanceolate, rather rigid, all entire, or the lowest ones sparingly 
or pinnatifid ; flowers purple. — Dry soil, Florida, and northward. July- S° 
90. MULGEDIUM, Cas. 
Heads many-flowered. Scales of the involucre imbricated, ‘the outer ones 
short. Receptacle naked. Achenia smooth, laterally compressed, narrowed wt 
a short beak, which is expanded into a ciliate disk at the apex. Pappus of 99 
pious white or tawny hairs.— Tall hetbs. Leaves pinnatifid or unc 
Flowers mostly blue. 
gU * Pappus white. 
1. M. acuminatum, DC. Smooth ; stem panicled above; leaves 0Y% 
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