962 CARDUACEAE 



fertile or sterile; corollas campanulate, funnelform, or trumpet-shaped, 5-toothed, 

 regular; anthers with lanceolate or subulate tips; style either 2-cleft and the 

 branches more or less recurved, truncate at the apex, with an erose or fimbriate 

 apex, or else entire and surmounted by an erose or fimbriate cup; achenes ellip- 

 soid, terete, usually glabrous, without pappus. 



Disk-flowers sterile, their styles undivided or with short erect branches; receptacle naked. 

 Annual or perennial herbs; style of the disk-flowers undivided, ending in a cup- 

 shaped penicillate appendix. I. DRACUNCTJLOIDES. 

 Low shrubs or undershrubs; style of the disk-flowers usually more or less 2-cleft, each 



branch erect with truncate penicillate or erose apex. II. FILIFOLIAE. 



Disk-flowers fertile, their styles 2-cleft; branches more or less recurved. 

 Marginal pistillate flowers present. 

 Receptacle hairy. 



Heads numerous, usually paniculate; plant more or less shrubby at the base. 



III. FRIGIDAE. 



Heads few, 1-12, racemose; plant low, herbaceous, from a rootstock, 1-3 dm. 



high. IV. LANATAE. 



Receptacle naked. 



Annual or biennial herbs with bipinnatifld leaves. V. ANNTJAE. 



Perennials. 



Leaves silvery or silky or glabrate, but not tomentose beneath. 



Plants low, herbaceous perennial, with rootstocks; heads many-flowered, 

 nodding in a simple racemose inflorescence; leaves divided into linear 

 or oblong divisions. VI. NORVEGICAE. 



Plants more or less shrubby at the base; heads paniculate. 



Leaves pinnately dissected into narrow divisions (glabrate forms of 



A. Abrotanum, A. graveolens and A. tennis). 

 Leaves cuneate, 3-toothed at the apex or the upper entire. 



XIII. BlGELOVIANAE. 



Leaves more or less tomentose beneath. 



Leaves not dissected into narrowly linear more or less divergent divi- 

 sions; these, if narrow, very few, directed forward and entire. 

 Leaves greener and glabrate above, at least in age. 



Heads 60-100-flowered; leaves twice pinna tifld with obtuse 

 divisions, the lower long-petioled. 



VII. FRANSERIOIDES. 



Heads 5 50-flowered ; leaves simple or once pinnatifid, or if bi- 

 pinnatifid, with acute lobes and sessile or short-petioled. 

 Leaves entire or with a few lobes, if dissected to near the 

 midrib, the lobes rather broad [except in A. mexicana}. 



VIII. VULGARES. 



Leaves deeply dissected to near the midrib; divisions linear 

 or oblong, usually more or less cleft. 



X. DlSCOLORES. 



Leaves white-tomentose on both sides. IX. GNAPHALOIDES. 



Leaves once or twice dissected into linear or filiform, more or less spread- 

 ing divisions. 

 Leaf-segments broadly linear or linear-lanceolate, usually again 



lobed or toothed. X. DISCOLORES. 



Leaf-segments narrowly linear or filiform, mostly revolute. 



Leaves once pinnatifid; plant herbaceous; style of the ray-flow- 

 ers long-exserted. XI. WRIGHTIANAE. 

 Leaves twice pinnatifid; plant suffruticose; style of the ray- 

 flowers short-exserted. XII. PONTICAE. 

 Marginal pistillate flowers wanting; receptacle naked. 



Shrubs 1-50 dm. high; leaves canescent, not with raised midribs. 



Heads in terminal panicles; leaves entire, 3-5-toothed to 3-5-divided at the 



apex. XIV. TRIDENTATAE. 



Heads axillary; leaves pinnatifid into linear divisions. XV. RIGIDAE. 

 Dwarf undershrubs, scarcely more than 1 dm. high; leaves pinnatifld into linear- 

 spatulate divisions, green, with the ribs raised beneath. 



XVI. PYGMAEAE. 



I. DRACUNCULOIDES. 



Leaves all entire or the lower 3-fid. 



Leaves densely pubescent when young. 1. A. glauca. 



Leaves glabrous. 



Involucre 3-4 mm. broad; lower stem-leaves 3-12 mm. wide; heads 30-100-flow- 

 ered; outermost involucral bracts almost as long as the inner. 



2. A. aromatica. 



Involucre 2-3 mm. broad; leaves 1-3 mm. wide; heads 20-40-flowered ; outer 

 bracts much shorter than the inner. 3. A. dracunculoides. 



Leaves, at least the lower, pinnatifid or bipinnatifid. 



Heads very small, 2-3 mm. broad, numerous in large leafy panicles; plants mostly 



tall, 3-10 dm. high. 

 Biennials; heads mostly erect; outer bracts acute. 



Plant glabrous or nearly so. 4. A. caudata. 



