COMPOSITAE (COMPOSITE FAMILY) 



803 



Annual ; Involucre 6-8 min. high, of linear-subulate loosely 



imbricated bracts 57. A. tubulatua. 



g. Leaves on branchlets broader h. 



h. Inflorescence loosely paniculate-corymbose. 



Bracts thin, uniform, linear-lanceolate ; rays few, white or 



pinkish, rarely wanting 54. A. acuminatu*. 



Bracts firm, oblong, the tips foliaceous ; rays numerous, 



violet 11. A. radula. 



h. Inflorescence definitely paniculate *. 



i. Bracts ascending, their tips not squarrose. 



Bracts regularly imbricated in several series. 



Bracts linear-attenuate 42. A. paniculatus. 



Bracts broad-linear or linear-oblong, with conspicuous 



elliptic or subrhombic green tips . . . . 43. A. salicifolius. 



Bracts subequal 45. A. longifolius. 



i. Bracts with spreading or squarrose tips, the outer mostly 



foliaceous 46. A. novi-belgii. 



d. Stem conspicuously pubescent j. 

 j. Bracts with definite firm subulate tips. 



Involucre hemispherical or campanulate, as broad as high ; leaves 



lanceolate to oblong-lanceolate .... (33) A. ericoides, v. platyphyllus. 

 Involucre turbinate, narrower than high . . (34) A. depauperatus, v. parviceps. 

 j. Bracts without firm subulate tips. 



Heads solitary or loosely paniculate-corymbose ; bracts thin, linear- 

 lanceolate, loosely imbricated ; rays whitish, violet, or rose-pink. 

 Leaves essentially uniform and crowded on the stem, entire or 



slightly toothed, blunt or acutish 



Upper leaves largest, coarsely toothed, long-acuminate 

 Heads paniculate or racemose ; bracts rather closely imbricated. 

 Bracts regularly imbricated in several series ; rays short, white 



to lavender. 

 Heads regularly paniculate ; bracts linear-attenuate ; leaves 



lanceolate (42) A. paniculatus, vars. 



Heads in more or less 1 -sided racemes; bracts generally with 



colored dilated midribs ; leaves lanceolate to oblong . . 40. A. lateriflorus. 

 Bracts subequal ; rays long, blue or violet ; stem densely villous 



(45) A. longifolius, v. viUicaulis. 



55. A. nemoraUs. 

 54. A. acuminatus. 



1. HELEASTRUM (DC.) B. & H. Pappus simple, coarse and rigid, the 

 stronger bristles somewhat clavate / bracts rigid, more or less foliaceous, 

 nearly equal. 



1. A. palud&sus Ait. Stems 3-7 dm. high, glabrous or nearly so; heads 

 rather few, racemose or spicate ; involucre 1 cm. high ; outer bracts lax, foli- 

 aceous ; rays purple ; leaves linear, entire. Kan. to Tex. , 

 N. C., and Ga. FIG. 918. 



2. BIOTIA (DC.) T. & G. Involucre obovoid-bell- 

 shaped, turbinate, or cylindric; the bracts regularly 

 imbricated in several rows, appressed, nearly destitute 

 of herbaceous tips ; rays 6-18 ; achenes slender ; pap- 

 pus slightly rigid, simple ; lower leaves heart-shaped, 

 petioled, coarsely serrate; heads in open corymbs 

 (rarely congested). 



* Eays white (sometimes colored in age) ; 

 branches of inflorescence without glands. 



918. A. paludosus. 



*- Involucre ovoid-bell -shaped or turbinate; plants simple, 

 rarely producing large tufted basal leaves. 



w- Leaves thin, smooth or sparsely hairy but not rough. 



2. A. divaricatus L. Stem slender, somewhat zigzag, 3-9 

 dm. high, glabrous or sparingly pilose ; leaves coarsely and 

 unequally serrate with sharp spreading teeth, taper-pointed, 

 ovate, ovate-lanceolate, or deltoid-ovate, all but the upper- 

 most heart-shaped at the base and on slender naked petioles ; 

 involucre 0-8 mm. high ; bracts thin, scarious, mostly obtuse 

 and ciliate, with inconspicuous green tips, the outer short and 

 oblong or oblong-triangular, the inner linear; rays 6-12. 



919. A. divaricatus 



