Compositae. 



8i 



343 Achenes compressed, Carduus XIV. 



343 Achenes 4-ribbed, Onopordium XV. 



344 Pappus much longer than the achene, . . Serratula XIII. 



344 Pappus not longer than the achene, . Centaurea XVII. 



345 Heads with a conspicuous ray, usually differently 



coloured to the disk, 352 



345 Heads all of one colour, ray not conspicuous, 353 



346 Leaves all radical, appearing after the flowers, 354 



346 Stems leafy, 355 

 347 Involucre imbricated, 349 

 347 Involucre simple Tragopogon I. 



348 Achenes with a beak, Lactuca V. 



348 Achenes without a beak, , , . . Sonchus VI. 



349 Stem leafy, 350 

 349 Scape leafless, Leontodon II. 



350 Outer bracts broadly cordate, . . Helminthia XXXVI. 



350 Bracts equal, Picris XXXVII. 



351 Beak short or none, 356 



351 Beak long, Taraxacum IX. 



352 Leaves all radical, scape i-flowered, . . Bellis XXX. 



352 Leaves not all radical, 357 



353 Achenes angled crowned by a large epigynous 



disk, leaves not downy beneath, . . . Tanacetum XX. 



353 Achenes obovate with a small disk, leaves downy 



beneath, Artemisia XXI. 



354 Heads in racemes, Petasites XXIV. 



354 Heads solitary, Tussilago XXVI. 



355 Heads discoid, 358 



355 Heads with a conspicuous ray, 360 



356 Pappus white soft deciduous, .... Crepis VII. 



356 Pappus brown brittle, Hieracium VIII. 



357 Bracts of the involucre with scarious margins. Chrysanthemum XXXI. 

 357 Bracts without margins, Matricaria XXXII. 



358 Bracts of the involucre leafy, 359 



358 Bracts of the involucre dry scarious, 362 

 359 Leaves entire, 361 . ../ , , ,y\^ 



359 Leaves pinnatifid, '^^^ T ^^ ^-^f*^^ /^ . . Senecio XXVIl. 



360 Bracts of the involucre imbricated, 363 



360 Bracts of the involucre in one row, with 



scales at the base Senecio XXVIl. 



