COMPOSITAE 321 



Heads in a terminal corymb. 29. A. acuininatiis. 



Heads solitary at the ends of slender branchlets and disposed in ra- 

 cemes or panicles. 

 Heads scattered, the peduncles prolonged, copiously scaly. 



30. A. dutnosiis. 

 Heads decidedly racemose or paniculate, the peduncles not con- 

 spicuously scaly. 

 Plant glabrous or pubescent, but not harsh : bracts of the involucre 

 acute or obtusish. 

 Heads paniculate, not in i-sided racemes. 



Blades of the cauline leaves of a lanceolate or narrowly oblong 

 type. 

 Heads mostly over 16 mm. broad. 

 Ligulesof the ray-flowers usually bluish violet : leaf-blades 



firm. 31. A. salicifolius. 



Ligules of the ray-flowers usually white : leaf-blades thin- 

 nish. 32. A. paniculatus. 



Heads mostly less than 16 mm. broad. 33. A. Tradescanti. 

 Blades of the cauline leaves of a linear-lanceolate or subulate 

 type. 

 Upper leaves with linear blades. 34. A. Faxonii. 



Upper leaves with subulate blades. 

 Stem paniculately branched and bushy. 



35. A. ericoides. 

 Stem nearly simple or with few ascending branches. 



36. A. Pringlei. 

 Heads racemose and disposed on one side of the branches. 



Blades of the cauline leaves of a broader type than linear or 

 linear-lanceolate, markedly toothed. 



Stem finely pubescent or glabrate. 37. A. lateriflorus. 



Stem villous. 38. A. hirsiiiicaulis. 



Blades of the cauline leaves linear or linear-lanceolate. 



39. A. viminens. 

 Plant very rough : bracts of the involucre obtuse. 



40. A. niultiflorus. 

 Leaves fleshy or succulent. 



Perennial plant : headsmostly over 12 mm. wide. 41. A. tenuifolius. 

 Annual plant : heads mostly less than 10 mm. wide. 



42. A. siibulatus. 



1. Aster divaricatus L. White Wood Aster. (Man. p. 949; I. F. 

 /• 3737-) lo open woodlands and thickets, in rather dry soil, Can. to 

 Man., Ga. and Tenu. — Pennsylvania: Northampton; Lancaster; 

 Huntingdon ; Ai^legheny ; Westmoreland. 



la. A. divaricatus cymulosus Burgess. (Man. p. 949.) N. Eng. 

 and N. Y, to Va. — Northampton. 



2. Aster tenebrosus Burgess. LoNG-r,EAVED Wood Aster. (Man, 

 p. 950; I. F. f. 3736.) In moist dark woodlands, N. Y. to Va. — Penn- 

 sylvania : Lancaster. 



3. Aster glomeratus (Nees.) Bernh. BERNHARDi's Aster. (Man. 

 p. 950; I. F. /. 3739.) In moist thickets, swamps or ravines, N. Y. and 

 Pa. — Pennsylvania : Ali^egheny. 



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