COMPOSITAE (COMPOSITE FAMILY) 



479 



61. Psilostrophe. 



62. Pericome. 



63. Hymenopappus. 



64. Leucampyx. 



65. Polypteris. 



Awns not retrorsely barbed or hispid, often at length 



deciduous. 



Ray-flowers fertile; achenes winged . . . 55. Ximenesta. 

 Ray-flowers neutral. 



Involucral bracts distinct, somewhat foliaceous 54. Helianthella. 

 Involucral bracts all more or less united at base 66. Coreopsis. 

 Awns retrorsely barbed or hispid. 



Involucral bracts united only at base . . .57. Bidens. 

 Involucral bracts united into a cup . . .58. Thelesperma. 

 Involucral bracts partly or wholly inclosing the ray achenes. 



Rays 1-5, inconspicuous, yellow ..... 59. Madia. 



Rays 8-12, conspicuous, white or rose 60. Layia. 



Tribe VI. HELENIEAE 



Herbage without oil-glands; not rank-scented but often aromatic. 

 Ligules persistent and becoming papery; plants more or less 

 woolly .......... 



Ligules deciduous or wanting. 



Achenes flat, with only marginal nerves ..... 



Achenes angled (not flat), nerved or striate. 

 Receptacle not chaffy. 



At least the tips of the involucral bracts petaloid or scar- 



ious. 



Heads rayless . '. '. . . . . Yw : 

 Heads radiate. 



Ligules white or yellowish ..... 



Ligules purple ....... 



Involucral bracts not petaloid or scarious. 

 Achenes 4-angled. 



Leaves all entire ....... .'v[ 



Leaves not all entire. 



Bracts of the involucre in 2 series, more or less 

 united . ...... 



Bracts of the involucre distinct. 

 Plants not glutinous or viscid. 



Flowers yellow ...... 



Flowers white or flesh-color . . , : ' .' 

 Plants glutinous or viscid . . 



Achenes 5-10-ribbed; herbage commonly impressed- 



punctate and resiniferous. 

 Pappus present. 



Involucral bracts erect. 



Leaves entire, usually linear . . . .71. Actinella. 



Leaves not entire. 



Herbage glabrous or becoming glabrate . 72. Hymenoxys. 



Low woolly alpine perennial, with enormous 



heads . . .... 73. Rydbergia. 



Involucral bracts spreading or reflexed. 



Leaves not decurrent on the stem, usually some 



of them parted .... 74. Dugaldea. 



Leaves decurrent on the stem, entire 75. Helenium. 



Pappus wanting ..... 76. Flaveria. 



Receptacle with bristle-like chaff ... 77. Gaillardia. 



Herbage with oil-glands, heavy or rank scented. 



Leaves pinnately divided ...... 78. Dysodia. 



Leaves entire, narrow ...... 79. Pectis. 



Tribe VH. ANTHEMIDEAE 



Receptacle chaffy, at least in part. 



Heads broad; rays conspicuous ...... 80. Anthemis. 



Heads narrow; rays short . . . . . . .81. Achillea. 



Receptacle naked. 



Heads solitary or corymbose. 



Receptacle conical, at least in age ..... 



Receptacle flattish or only moderately convex. 

 Heads radiate . . . . . . 



Heads rayless ......... 



Heads several to many, spicate or racemose-paniculate, discoid 



67. Platyschkuhria. 

 66. Eriophyllun. 



68. Bahia. 



69. Chaenactis. 



70. Hulsea. 



82. Matricaria. 



83. Chrysanthemum. 



84. Tanacetum. 



85. Artemisia. 



Tribe VHI. SENECIONEAE 



Flowers white or purple; rays wanting 

 Flowers yellow. 

 Leaves opposite. 



Involucral bracts spreading . 

 Involucral bracts erect or connivent 

 Leaves alternate. 



Shrubs; heads rayless, 4-9-flowered 

 Herbs; rays usually present, flowers many 



86. Petasites. 



87. Haploesthes. 



88. Arnica.* 



89. Tetradymia. 



90. Senecio. 



