SEREAIULA. — -CENTATJEEA. 197 



St. about 3 feet high. L. deeply cordate-prolonged ; petioles 

 (hollow) scarcely angular, slightly furrowed. Stalks of the heads 

 rather long, those of the lower heads, longest. ' Heads usually 

 with much wool, twice as large; as those of ^. mimes. Fr. dark 

 brown with a few. paler spots towards the top. — Waste places 



B.vin. r ^ i- v^^ 



Seotion2. iS.BiJ.ffi^ri/'i.B.^.: Heads many-flowered; flowers 

 aU, tubular, perfect or dioecious, the exteiiial rpw, sometimes 

 female. Involucre of many rows of distinct phyUaries. Fila- 

 ments distinct. Pappus in many rows of dift'erent lengths, inner 

 row longest, hairlike or feathery, surrounded by a margin'. 



28. 'Seeeat'fla Linn. Saw-wort. 



1. ^. tinctdria (Ti.); 1. with bristly serratures pinnatifid some- 

 what lyrate, heads oblong, phyll. ovate adpresseJ, .inner ones 

 linear coloured. — St. 3. 16. — St. 2 — ^3 feet high, straight, erect, 

 angular, branched above. ' L. pinnatifid or lyrate, rarely entire. 

 Fl-. purple. — a. heads stalked in a lax corymb.^/3. iS monticola 



(Bor.) ; heads subsessile few larg;e close together Groves and 



tiiokets. P. Vin. E. 



Section?. CBNTAURBM. Heads many-flowered, discoidal; 

 outer row of fl. usually barren, enlarged, irregular. PhyUaries 

 in many, rows. Filaments distinct. Pappus in many rows of 

 different lengths, second row longest, setaceo-pilose, placed 

 within the margin which surrounds the epigynous disk, rarely 0. 



29. CENTAtr'REA lAnn. Knapweed. 

 * Fhyll. with a scarious pectinate not decurrent appendage. 



\C. Jdcea (L.) ; phyll.-appendages erect founded, pappus 0, 

 1. linear-lanceolate lower ones broader and toothed. — Inv. pale 

 brown; outermost phyll. with deeply,, pinnatifid appendages, 

 few innermost entire, the rest irregularly jagged. Heads radiant. 

 — Not na:tive„ i P. VHL IX.] E. 



1. C. nigra (L.) ; phyll. -appendages patent or erect lanceolate 

 or ovate-lanceolate pectinate their teeth subulate, pappus or 

 short deciduous, 1. lanceolate or ovate-lanceolate acute. — St. 

 i — 2 ft., high. L. green; lower narrowed into long stalks, entire 

 or sinuate-dentate ; upper se.ssUe. Heads globose. Few inner- 

 most phylL-appendages torn. Fr. oblong, downy. — a. C. nigra 

 (L.) ; phyU. -appendages erect or patent ovate-lanceolate usually 

 quite covering the phyll. their teeth long. Mart. Fl. Rust. 130. 

 iJ. XXV. 761. St. usually with long 1-headed branches. Pappus 

 or short. Heads sometimes radiant. — ,3. C. ideeipiens (Thuill ) ; 



