COMPOSITAE (COiMPOSITE EWMILY) 



803 



Annual ; involucre 6-S mm. high, of Unear-subulate loosely 



imbricated bracts 57. ^. subulaius. 



g. Leaves on branchlets broader h. 



h. Inflorescence loosely paniculate-corymbose. 



Bracts thin, uniform, Iir).3ar-lanceolate ; rays few, white or 



pinkish, rarely wanting 54. ^. acuminatus. 



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



violet 11.-4. radula. 



h. Inflorescence definitely paniculate i. 



i. Bracts ascending, their tips not squarrose. 



Bracts regularij- imbricated in several series. 



Bracts linear-attenuate 42. A. paniculatus. 



Bracts broad-linear or linear-oblong, •with conspicuous 



elliptic or subrhombic green tips . . . , 43. ^. salicifolius. 



Bracts subequal 45. A. longifoliits. 



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



foliaceous 46. ^. novi-helgii. 



d. Stem conspicuoush' 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. jdatyphyllus. 

 Involucre turbinate, narrower than high . . (3-4) A. depauperatus, \. 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 55. A. nemoralis. 



Upper leaves largest, coarsely toothed, long-acuminate . . 54. ^. acuminatus. 

 Heads paniculate or racemose ; bracts rather closely imbricated. 

 Bracts regularly imbricated in several series ; rays short, white 

 to lavender. 

 Heads regularly paniculate ; bracts Un ear-attenuate ; leaves 



lanceolate (42) A. paniculaiua, vars. 



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



colored dilated midribs ; leaves lanceolate to oblong . .40.-4. lateriflorus. 

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



(4.5) A. longi/olius, v. villicaulis. 



§ 1. HELEASTRUM (DC.) B. & H. Pappus simple, coarse and i-igid, 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. BIOTIA (DC.) T. & G. Invohicre obovoid-bell- 

 shaped, turbinate, or cylindric ; the bracts regularly 

 imbricated in several roics, oppressed, nearly destitute 

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

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

 petioled, coarsely serrate; heads in open corymbs 

 {rarely congested). 



* Bays white (sometimes colored in age) ; 

 branches of inflorescence without glands. 



^ Invohicre ovoid-bell-shaped or turbinate; plants simple, 

 rarely producing large tufted basal leaves. 



•M. 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-lanceolate, or deltoid-ovate, all btit the upper- 

 most heart-.«;haped at the base and on slender naked petioles ; 

 involucre (5-8 mm. high ; bracts thin, .scarious. mostly obtuse 

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

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



paludosus. 



919. A. divaricatus 



