COMPOSITE. 51 



or thickened upward, minutely papillose or puberulous, or glabrous ; the stigmatic 

 lines only near the base and inconspicuous. Leaves either opposite or alternate. 

 Flowers never j'ellow, at most ochroleucous. 



* Akenes 5-anglecl, destitute of intervening ribs : corolla-lobes or teeth usually short. 



-K- Pappus various, but never wholly capillary, sometimes obsolete or wanting. 



++ Involucre 5-flowered (sometimes 3-4-flowered), cylindrical, of 5 or 6 mostly equal rather 



rigid bracts : receptacle small, naked : corolla narrow. 



4. STEVIA. Akenes linear, slender, sometimes compressed. Pappus coroniform-paleaceous 

 or aristiform, or composed both of awns (one or more) and short scales. 



-H- -H- Involucre manj'-flowered, lax, of 12 to 18 herbaceous or submembranaceous equal and 

 nerveless bracts : receptacle naked : corolla abruptly much dilated above the narrow tube, 

 rose-purple or flesh-color. 



5. SCLEROLEPIS. Eeceptacle conical. Style-branches elongated, filiform-clavate. 

 Akenes with an inane stipitiform base. Pappus conspicuous, of 5 broad and very obtuse or 

 truncate cartilaginous nerveless scales. Leaves verticillate. 



6. TRICHOCORONIS. Receptacle convex. Style-branches comparatively short, linear, 

 flat or flattish-filiform, not enlarged upward. Akenes not contracted above the basal callus. 

 Pappus minute or small, multisetulose-coroniforra. Leaves opposite or alternate. 



++++++ Involucre many-flowered, campanulate or hemispherical, of 2 or more series of 

 striate-nerved bracts, more or less imbricated : receptacle flat or convex : corolla rather 

 narrow : akenes not stipitate-attenuate, but with a strong basilar callus. 



7. AGERATUM. Involucre of mostly narrow bracts in 2 or 3 series, not conspicuously 

 unequal. Receptacle either naked or paleaceous. Pappus simple, paleaceous, and the palece 

 either muticous or aristate, or coroniform ; the crown sometimes almost obsolete. 



8. HOFMEISTERIA. Involucre more imbricated ; outer bracts successively shorter. Re- 

 ceptacle naked. Pappus of 2 to 12 slender or capillary bristles equalling the narrow corolla, 

 and as many or fewer alternating or exterior short and thin paleae. 



-1— H— Pappus wholly of capillary and. mostly uniserial bristles ; 

 ++ These merelj^ scabrous, indefinitely numerous : receptacle naked. 



9. MIKANIA. Involucre 4-flowered, composed of 4 or sometimes 8 similar and equal thin 

 bracts, with or without a loose and somewhat herbaceous subtending one. Receptacle 

 small. Stems (at least in ours) twining. 



10- EUPATORIUM. Involucre few-many-flowered, of more than 4 bracts. Neither 

 twining nor climbing. 



•H- -H- These long-plumose, rather few : receptacle naked. 



11. CARMINATIA. Involucre several-flowered, cylindraceous, of several lanceolate-linear 

 3-5-striate thin imliricated bracts, the exterior shorter. Receptacle small, flat, naked. Co- 

 rollas slender, 5-toothed. Style-branches filiform, acutish. Akenes slender, narrowish at 

 the apex. Pappus of 10 to 18 bristles, which ai-e slightly coherent at base in a single series, 

 plumose with long arachnoid hairs, deciduous together. 



* * Akenes 10;costate or striate. 

 -I— Bracts of the involucre not herbaceous, striate-nerved, conspicuously so when dry, regu- 

 larly imbricated; the outer ones successively shorter : receptacle naked : corollas slender, 

 5-toothed at summit ; the teeth mostly glandular externally : pappus a single series of 

 plumose or scabrous capillary bristles : heads few-many-flowered. 



1 2. KUHNIA. Pappus conspicuously plumose. Bracts of the involucre narrow, in few 

 series. Leaves nearly all alternate. 



13. BRICKELLIA. Pappus from barbellate or subplumose to merely scabrous. Leaves 

 opposite or alternate. 



4— -i— Bracts of the involucre somewhat herbaceous or partly colored, inconspicuously when 

 at all striate or nerved, even when dry, 



++ "Well imbricated, the outer successively shorter : leaves punctate, entire : flowers rose- 

 color, or abnormally and rarely white. 



