802 



COMPOSITAE (composite FAMILY) 



Rays 6 mm. or less long ; leaves slightly serrate . . 41. A. TVadescanti. 



Rays longer ; leaves entire . . (42) A. paniculatus, v. hellidifiovux. 

 Branches divaricate ; small heads in 1-sided racemes . 89. A. vimineun. 



Branches ascending, terminated by solitary heads (39) A. mmineus, v. saxatilis. 



Rays violet or rose-pink (exceptionally white) 

 Leaves at most 4.5 cm. long, becoming revolute . . 55 



Leaves longer, plane 44 



V. Involucre more than 5 mm. high Y. 

 T. Bracts with definite firm subulate tips 

 Y. Bracts without firm subulate tips Z. 



A. 

 A. 



nemoraUa. 

 junceus. 



32. A. polyphyllus. 



Leaves at most 4.5 cm. long. 



52. A. linariifoliua. 

 55. A. nemoralis. 



57. A. suhulatus. 



58. A. anguatua, 



59. A.frondoaua. 



A. tenwifoliua. 

 A. paludoatia. 



IT. 



A. junceiia. 



A. 

 A. 

 A. 



mulUjlorua. 



comrnutatua. 



amethyatinua. 



Stems many, rigid, from a woody caudex ; bracts firm, the 

 inner blunt ; rays blue-violet ...... 



Stem single, from a slender rootstock ; bracts thin, linear- 

 attenuate ; rays rose-pink 



Z. Leaves longer a. 

 a. Annuals, with inconspicuous rays. 



Bracts definitely imbricated, linear or linear-subulate 

 Bracts subequal, the outer foliaceous. 

 Leaves linear-attenuate ; ray.s shorter than the style 

 Leaves linear-oblanceolate to spatulate ; rays longer than 



the style 



a. Perennials, with mostly conspicuous rays b. 

 b. Bracts firm, lanceolate. 



Bracts unequal, regularly imbricated, not foliaceous . 56. 

 Bracts subequal or imbricated, with spreading foliaceous 



tips 1. 



b. Bracts thin, linear or linear-lanceolate. 



Bracts with conspicuous elliptic or subrhombic green tips. 

 Heads terminating minutely foliose-bracteolate branch- 

 lets 38. ^. dumoaua. 



Heads paniculate, or if few on leafy (not minutely 



foliose-bracteolate) branches 43. ^. aalidfoliua. 



Bracts without conspicuous colored tips. 



Rays white ; bracts very narrowly Hnear-attenuate, 



regularly imbricated, 4-6 mm. long (42) A. paniculatua, v. helUdiflorua. 

 Rays violet or rose-pink ; bracts linear-lanceolate, less 

 definitelv imbricated, mostly longer . . .44. 

 Stem conspicuously pubesi!ent. 



Involucral bracts (or at least the outer ones) bristly-ciliate. 

 Leaves crowded, rigid ; rays white (rarely purple-tinged). 



Heads 5-6 mm. high 36. 



Heads 7-9 mm. high 87. 



Leaves not rigid ; rays blue 35. 



Involucral bracts not bristlj^-ciliate. 

 Bracts with firm suJbulate tips ; short rays usually white. 

 Involucre hemispherical or campanulate, as 6road as high (33) A. ericoidea, v. villoaua. 

 Involucre turbinate, narrower than high . . (.34) A. depauperatua, \. parvicepa. 

 Bracts thin, linear-attenuate, without firm subulate tips ; stem 



puberulent ; long rays violet or rose-pink . . . .55. 

 T. Stem-leaves lanceolate or broader c. 



c. Heads in flat-topped corymbs ; rays white or whitish (not blue or violet). 



Leaves rigid, linear-lanceolate ; pappus simple 53. 



Leaves not rigid, broader ; pappus double. 



Involucre 3-4.5 mm. high ; leaves lanceolate to ovate . . . 50. 

 Involucre 5-7 mm. high ; leaves obovate to oblong . . .51. 

 c. Heads paniculate or racemose d. 

 d. Stems glabrous or essentially so e. 

 e. Involucre 5 mm. or less high. 



Bracts with definite firm subulate tips 33. 



Bracts without firm subulate tips. 

 Heads in more or less 1-sided racemes. 



Leaves narrowly lanceolate, scarcely serrate ; bracts linear- 

 attenuate 39. ^. vimineus. 



Leaves broader, serrate ; bracts with the midrib dilated 



upward and rather conspicuous 



Heads on ascending-paniculate branches. 

 Bracts linear -attenuate. 

 Heads (including rays) 1-1.5 cm. broad; 



slender and green .... 

 Heads larger ; bracts green chiefly at tip . 

 Bracts broad-linear or linear-oblong, with 

 elliptic or subrhombic green tips . 

 6. Involucre more than 5 mm. high /. 



'/. Bracts with definite firm subulate tips 



/. Bracts without firm subulate tips g. 

 g. Leaves on branchlets reduced to rigid subulate bracts. 



Perennial; involucre 9 mm. or more high, of lirui closely 

 imbricated bluntish bracts 



A. nemoralia. 



A. piarmicoidea. 



A. 

 A. 



umbellatua, 

 injirmua. 



A. ericoidea. 



40. A. lateriflorus. 



bracts very 



conspicuous 



41. 



42. 



A. Tradeacanti. 

 A. paniculatua. 



43. A. aalidfoliua. 

 32. A. polyphyllua. 



28. A. turhinellua. 



