COMFOSIT.E. (composite FAMILY.) 207 



Pappus clear white (except in one Mulgedium). 

 Achenia conspicuously beaked. No. 



Achenia ribbed. Stemless herbs ...... TARAXACUM. 94 



Achenia flat. Stems leafy LACTUCA. 96 



Achenia bealiless or nearly so. 



Flowers blue. Achenia sliglitly beaked MULGEDIUM. 96 



Flowers yeUow. Achenia beakless SONCHUS. 97 



Suborder I. TUBUI.IFI.ORiE. 



Tribe I. VERNONIACE^E. Heads discoid; the flowers all tubular and 

 perfect: branches of the stijle terete, Jj I i form, hairy all over; the stigmatic 

 lines only on the lower part. — Herbs, with edternate leaves and purple 

 flowers. 



1. VERNONIA, Sclireb. Iron-weed. 



Heads many-flowered, the flo-\\ers all equal and tubular. Involucre shorter 

 than the flowers ; the scales closely imbricated in several rows. Receptacle 

 naked. Achenia cylindrical, ribbed. Pajjpus double; the exterior consisting 

 of very sliort scale-like bristles, tlie intei-ior of copious capillary bristles. — 

 Perennial herbs, with alternate leaves, and corymbose purple flowers. 



1. V. oligophylla, Michx. Stem nearly naked ; leaves rough above, 

 pube.scent beneath, denticulate ; those at the ba.se large, oval or oblong, the 

 others small, distant, lanceolate ; corymb few-flowered, spreading ; involucre 

 bell-shaped, the scales lanceolate, acuminate, fringed. — Damp pine barrens. 

 July. — Steni 2° high, sparingly branched. 



2. V. Noveboracensis, Willd. Stem more or less pubescent, branched 

 above ; leaves lanceolate, serrate, mostl}- roughish above, smooth or pubescent 

 beneath; corymbs spreading; involucre hemispherical, the scales fringed, 

 ovate, ending in a long filil'orni point, or simply acute. — River banks and 

 low ground. July -Sept. — Stem 3°-G° high. Scales of the involucre 

 purple, and usually covered with web-like hairs. 



Var. latifolia, Gray. Stem 2°-3°hign; lower leaves oval or oblong, 

 coarsely serrate, paler beneath, the upper lanceolate, entire ; scales of the 

 involucre fringed, acute. — Dry woodlands, Georgia and Florida. July. 



3. v. Baldwinii, Torr. Tomentose; stem 2° -3° high ; leaves ovate- 

 lanceolate, acuminate, serrulate; heads rather small and crowded, globose, 

 canescent ; scales of the involucre appressed, with spreading or recurved tips; 

 achenia pubescent. — W. Tennessee {Gatlinger), and westward. 



4. V. altissima, Nutt. Stem 4°-10° high, smooth; leaves lanceolate 

 or oblong, tlie lower coarsely serrate, mostly glabrous ; corymlis spreading ; 

 heads scattered, the scales smooth, obtuse, appressed ; achenia slightly his])id. 

 — Low ground, chiefly in the upper districts. July - August. 



5. V. fasciculata, Michx. Stem slender, smooth, 2° -5° high, very 

 leafy; leaves linear-lanceolate, varying to ol)long, acuminate, smooth above, 

 puncticulate ; heads crowded ; scales of the involucre downy on the margins, 

 acute ; achenia smooth. — River banks, Tennessee, and westward. August. 



