572 226. COMPOSITAE 



274. Corolla of the marginal flowers strap-shaped, but shorter than the style, 



or thread-shaped, yellowish or whitish. — Species 80. Some of them 

 yield condiments, medicaments, or insect-poison. {Marsea Adans., 



including Webbia Schultz) Conyza Less. 



Corolla of the marginal flowers strap-shaped, longer than the style. In- 

 volucral bracts in two rows. Herbs or undershrubs 275 



275. Ray-flowers yellow. Heads in corymbs. — Species 33. Southern and 



tropical Africa Nidorella Cass. 



Ray-flowers red or white. (See 232.) Erigeron L. 



276. (267.) Ray-flowers yellow, sometimes reddish when old, or wanting. 



Pappus of bristles. [Subtribe solidagininae.] 277 



Ra3^-flowers white, blue, or red 289 



277. Heads with all the flowers hermaphrodite ; the inner flowers sometimes 



sterile 278 



Heads with the inner flowers hermaphrodite and surrounded by one row 

 of female or neuter marginal flowers 286 



278. Involucral bracts in one row or in two very unequal rows (the outer of 



much smaller bracts). Fruits 3 — lo-ribbed. Herbs 279 



Involucral bracts in two subequal rows or in 3 or more rows. . . . 280 



279. Hairy appendages of the style-branches short. Pappus of bristles. 



Leaves radical. — Species i. West Africa. . . Psednotrichia Hiern 



Hairy appendages of the style-branches long. Pappus of hairs. Leaves 



alternate. — Species 20. Tropical and South-west Africa. (Including 



Crassocephalum Moench, under Senecio L.) . . . . Gynura Cass. 



280. Pappus-bristles in i row. Shrubs. Leaves linear. Heads in leafy 



corymbs 281 



Pappus-bristles in 2 or more rows 282 



281. Fruits turgid, 5-ribbed. — Species i. South Africa (Orange River Colony). 



Pentheriella O. Hoffm. & Muschler 



Fruits compressed. — Species 13. South Africa. Some are used as 



ornamental plants Chrysocoma L. 



282. Pappus-bristles in 2 very unequal rows, the outer of very short, sometimes 



scale-Hke bristles. Fruits compressed 283 



Pappus-bristles in 2 subequal rows or in 3 or more rows 284 



283. Outer pappus-bristles scale-like. Hairy appendages of the style-branches 



linear, obtuse. Herbs. Leaves opposite. — Species 2. Southern 



West Africa. {Adenogonum Welw.) .... Engleria O. Hoffm. 



Outer pappus-bristles hair-like. Hairy appendages of the style-branches 



lanceolate. Shrubs. — Species 3. South Africa. . . . Fresenia DC. 



284. Stem woody, shrubby. — Species 33. South Africa to Damaraland. 



Pteronia L. 

 Stem herbaceous. Fruits compressed. Pappus-bristles in 2 or 3 rows. 285 



285. Leaves decurrent. Flowers yellow. Heads in corymbs. — Species 2. 



South Africa. (Under Chrysocoma L.) . . . Heteromma Benth. 

 Leaves not decurrent, (See 232.) Aster L., 



