COMPOSITAE (COMPOSITE FAMILY) 



803 



66. A. nemoralfa. 

 54. A. acuminatut. 



Annual ; Involucre 6-S mm. high, of linear-subulate loosely 



imbricated bracts ......... 81. A. tubulalut. 



g. Leaves on branchlets broader h. 



h. Inflorescence loosely paniculate-corymbose. 



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



pinkish, rarely wanting ....... 64. A. acuminatut. 



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



violet ........... 11. A. radula. 



h. Inflorescence definitely paniculate i. 



i. Bracts ascending, their tips not squarrose. 



Bracts regularly imbricated in several series. 

 Bracts linear-attenuate ....... 42. A. paniculatut. 



Bracts broad-linear or linear-oblong, with conspicuous 



elliptic or subrhouibic green tips . . . . 48. A. alicif<>lius. 



Bracts subequal ......... 45. A. iongifolius. 



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



foliaceous ...... . . . . 46. A. nori-belgii. 



d. Stem conspicuously pubescent j. 4 



j. Bracts with definite firm subulate tips. 



Involucre hemispherical or campanulate, as broad as high; leaves 



lanceolate to oblong-lanceolate .... (83) A. ericoides, v. plutyphyllwt. 



Involucre ttirbinate, narrower than high . . (84) A. depauperates, v. 

 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 



rpl'i-r 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. lateriJlorvH. 

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



(46) A. longifolius, v. viUicaulig. 



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. paludbsus 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. BI6TIA (DC.) T. & G. Involucre obovoid-bell- 

 shaped, turbinate, or cylindric; the bracts regularly 

 imbricated in several rotes, oppressed, nearly i7.-stitxte 

 of herbaceous tips ; rays (5-18 ; achenes slender ; pap- 

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

 petioled, coarsely serrate; heads in open corymbs 

 (rarely congested). 



* Says white (sometimes colored in age); 

 branches of inflorescence without glands. 



918. A. paludosus. 



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

 rarely producing large tufted basal leaves. 



++ 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 icith sharp spreading teeth, taper-pointed, 

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

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

 involucre 6-8 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 0-12. 919. A. divaricatus 



