COMPOSITAE (COMPOSITE FAMILY) 775 



+- +- Leaves alternate ; pappas soft-capillary, copious. 



77. Erechtitcs. Heads discoid. Flowers whitish, the outer pistillate with filiform corollas. 



78. Cacalia. Heads discoid. Corollas white or cream-colored, 5-cleft. 

 T'.i Senecio. Heads usually radiate. Corollas yellow, 5-toothed. 



Tribe IX. CYNAREAE. Flowers all tubular and perfect (the outer ray-like and neutral In DOS. 

 86 and $7). Involucre much Imbricated. Anthers caudate, long-appendaged at tip. Style- 

 branches short or united, obtuse, unappendaged, smooth, with often a pubescent ring below. 

 Pappus mostly bristly. Leaves alternate. 



* Achenes attached by the base ; flowers all alike. 

 *- Leaves not prickly ; style-branches partly distinct ; filaments glabrous. 



80. Arctium. Involucral bracts hooked at the tip. Pappus of short rough bristles. 



+ *- Leaves prickly ; style-branches coherent, usually a pubescent ring below. 

 +* Involucres 1-flowered, aggregated into dense globose heads. 



81. Bchinops. General involucre small, reflexed, and hidden. Coarse, thistle-like herbs, with 



large globular (compound) heads of pale flowers. 



** ++ Involucres many-flowered. 



Filaments papillose-pilose, free. 



a. Receptacle densely bristly. 



82. Cardans. Pappus-bristles not plumose. 

 88. Cirsium. Pappus-bristles plumose. 



b. Receptacle deeply honeycombed, scarcely or not at all bristly. 



84. Onopordum. Pappus-bristles not plumose. 



= = Filaments glabrous, united into a tube. 



85. Silybum. Involucral bracts ending in a long stout splnescent appendage, spreading or 



redezed. Receptacle densely bristly. Pappus-bristles not plumose. Stout thistle-like 

 herbs, with large heads. 

 * * Acbenes obliquely attached ; marginal flowers often enlarged and ray -like. 



86. Centaurea. Pappus of several series of short scales or bristles or none. Flowers red, 



purple, blue, white, or rarely yellow. 



87. Cnicus. Pappus of 10 short horny teeth, 10 long bristles, and 10 shorter ones. Flowers 



yellow. 



SERIES LT. LIGULIFL6RAE 



Corolla ligulate in all the flowers of the head, and all the flowers perfect. 

 Herbs, wiih milky juice. Leaves alternate. 



Tribe X. CICHORlEAE. Characters of the series. 



* Pappus none ; annuals. 

 +- Leafy-stemmed. 



88. Lapsana. Involucre cylindrical, calyculate-bracteate at base. 



89. Serinia. Involucre not calyculate. 



- (- Leaves all basal. 



90. Arnoseris. Involucral bracts narrow, at length carinate-thickened. 



* * Pappus chaffy, or of both chaff and bristles. 



91. Cichoriom. Involucre double. Pappus a small crown of many bristle-form scales. 



92. Krigia. Involucre simple, not calyculate. Pappus of both chaff and bristles. 



* * * Pappus plumose. 



95,. Hypochaeris. Involucre calyculate. Achenes fusiform, the inner produced Into long slender 

 hfuks. Leaves radical. 



94. Leontodon. Similar. Achenes uniform. 



95. Picris Outer involucral bracts spreading. Achenes terete, not beaked. Stems leafy. 



96. Tragopogon. Involucre simple, not calyculate. Achenes long-beaked. Steins leafy. 



