COMPOSITiE. 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 yellow, at most ochndeucous. 



* Akeues 5-angled, destitute of iuterveinng ribs : corolladobes or teeth usually short. 



•i— Pappus various, but never wholly capillary, sometimes obsolete or wanting. 



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



rigid bracts : receptacle small, naked : corolla narrow. 



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

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



-w- ++ Involucre many-flowcre<I, lax, of 12 to 18 herliaceous or sid)membrauaceoas equal and 

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

 rose-pnrple or flesh-color. 



5. SCLEROLEPIS. Receptacle conical. Style-ln-anches elongated, filiforni-clavate. 

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

 truncate cartilaginous nerveless scales. Leaves verticillatc. 



6. TRICHOCORONIS. Eeceptacle convex. Styledirauchcs comparatively short, linear, 

 flat or flattisli-flliforni, not enlarged upward. Akenes not contracted above the basal callus. 

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

 ++++++ Involucre many-flowered, campanulate or hemisplierical, 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 

 une([ual. Eeceptacle either naked or paleaceous. Pappus simple, paleaceous, and the palete 

 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 capilhuy bristles equalling the narrow corolla, 

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



-1— -i— Pappus wholly of cajjillary and mostly uniserial bristles ; 



-H- These merely scabrous, indefinitely numerous : receptacle naked. 



9. MIKANIA. Involucre 4-flowered, composed of 4 or sometimes 8 sinnlar and equal tlun 

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

 small. Stems (at least in ours) twining. 



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

 twining nor climbing. 



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



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

 3-5-striate thin iiiil)ricated 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 are 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 iml)ricated ; the outer ones successively shorter : receptacle naked : corollas slender, 

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

 plumose or scal)rous capillary bristles : heads few-many-flowered. 



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

 series. Leaves nearly all alternate. 



13. BRICKELLIA. Pappus from barbellato or sulqdumose to merely scabrous. Leaves 

 opposite or alternate. 



-•— -i— Bracts of the involucre somewhat herbaceous or partly colored, inconspicuously wlien 

 at all striate or nerved, even when dry, 



•H- Well iniliricated, tlic outer successively shorter: leaves punctate, entire: flowers rose- 

 color, or altnornially and rarely white. 



