COMPOSITE. 51 



or thickened upward, minutely papillose or puberulous, or glabrous; the stum-ilk- 

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

 Flowers never yellow, at most ochroleucous. 



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



-f- 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-palcaceous 

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



H. ++ Involucre many-flowered, lax, of 12 to 18 herbaceous or submembranaceous equal and 

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

 rose-purple or flesh-color. 



5. SCLEROLEPIS. Receptacle conical. Style-branches elongated, filifonn-clavate. 

 Akeues with an inane stipitiform base. Pappus conspicuous, of 5 broad and u n obtuse or 

 truncate cartilaginous nerveless scales. Leaves verticillate. 



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

 flat or ilattish-filiform, not enlarged upward. Akeues not contraeied above the basal callus.' 

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



H- -H- -H- Involucre many-flowered, campanulate or hemispberical, of 2 or more series of 

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

 narrow : akeues not stipitate-atteuuate, 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 palea? 

 either muticous or aristate, or corouiform ; 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 palere. 



f -i Pappus wholly of capillary aud mostly uniscrial bristles; 

 H- These merely 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. Recepi .-. 

 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. 



1 1. CARMINATIA. Involucre several-flowered, cylindraceous, of seyeral lanceolate linear 

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

 rollas slender, 5-toothed. Style-branches filiform, acutish. Akeues slender, narrowisli at 

 the apex. Pappus of 10 to 18 bristles, which are slightly coherent at base in a single scries, 

 plumose with loug 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. 



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

 series. Leaves nearly all alternate. 



13. BRICKELLIA. Pappus from barbellate or subphunose to merely scabrous. Lca\cs 

 opposite or alternate. 



K. H__ Bracts of the involucre somewhat herbaceous or partly colored, inconspicuously when 

 at all striate or nerved, even when dry, 



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

 color, or abnormally aud rarely white. 



