Family 2. CARDUACEAE 

 Tribe 10. HELENIEAE 



Per Axel Rydberg 



Heads radiate or discoid. Ray-flowers, when present, pistillate and usually 

 fertile (except in Gaillardia and Helenium); corollas usually ligulate (in 

 Amblyopapptis tubular, in Lembertia and Microspermum irregularly 3-5- 

 toothed, in Blennosperma and Baeria sometimes wanting). Disk-flowers her- 

 maphrodite, mostly fertile or rarely sterile, with actinomorphic, 5- or more 

 rarely 3- or 4-toothed corollas (in Chaenactis the marginal ones sometimes 

 enlarged and irregular). Involucral bracts mostly herbaceous and green, 

 rarely with dry scarious margins, except in the first subtribe mostly in 1 or 2 

 series or subtended by an external calyculum of smaller bracts. Receptacle 

 without paleae (except in Leucampyx, and sometimes a few between the rays 

 and the disk in Helenium), but in Gaillardia and Clappia and in species of 

 Chaenactis and Flaveria bristly, in Whitneya woolly, and in Baeria pilose. 

 Style-branches mostly flattened, more or less hispidulous and often ap- 

 pendaged. Pappus of scales (squamellae) or stiff awns, or wanting. 



Involucral bracts usually broad, in 3-5 series, imbricate, the 



outer shorter; ray -corollas deciduous or none. 

 Involucral bracts in 1—2 series, nearly equal in length, or 

 rarely with 1—3 small outer calyculate bracts. 

 Ray-corollas persistent on the achenes and falling off with 



them, marcescent. 

 Ray-corollas deciduous from the achenes or none. 

 Achenes flat with only marginal ribs or veins. 

 Achenes distinctly 3— 5 -angled, or if less distinctly so, 

 then obconic. 

 Style-branches either short or with a distinct ap- 

 pendage, not hispidulous to or below the 

 fork ; either disk- or ray-corollas or both yel- 

 low, if purple the involucre not narrow. 

 Bracts of the involucre wholly herbaceous or 

 somewhat chartaceous at the base, with- 

 out scarious margins. 

 Achenes either prismatic, or clavate-ob- 

 pyramidal, i. e., long and slender, 

 several times as long as broad, but 

 gradually tapering to the base; throat 

 of the disk-corollas mostly campanu- 

 late or funnelform, rarely much longer 

 than the tube; bracts appressed, usu- 

 ally broad. 

 Receptacle flat or convex and rounded 

 at the apex. 

 Achenes prismatic; pappus partly or 

 wholly of awns or in Amauria a 

 callous crown. 

 Achenes clavate-obpyramidal ; pap- 

 pus squamellate or rarely want- 

 ing. 

 Involucral bracts distinct, not at 

 all enclosing the ray-achenes; 

 plant rarely floccose (except 

 Hulsea) . 

 Involucral bracts either united 

 below or very concave and 

 partly enclosing the ray- 

 achenes; plants more or less 

 floccose. 



Voeume 34, Part 1, 1914] 



Subtribe 1. JattmEanaE. £_ 



Subtribe 2. Riddellianae. 

 Subtribe 3. Peritylanae. 



Subtribe 4. Amaurianae. 



Subtribe 5. Bahianae. 



Subtribe 11. Eriophyelanae. 



