310 SYNGENESIA FRUSTRANEA. ICentaurea. 



leaves angiilato-dentate sublyrate, upper ones lanceolate, with or 

 ■\vitliout a ray, pappus very short tufted. E. Sot. t. 278. — /3. 

 flowers radiant. — C. niyrescens, Willd. 



Meadows and pastures, frequent. Fl. June — Aug. I4.. — Stem 2 — 3 

 feet high. Leaves scabrous. Scales of the involucre almost black, the 

 teeth brown. Florets purple, numerous. Sir J. E. Smith describes the 

 scales of the calyx as having erect teeth or cilise, whicb I do not find to 

 be the case. The radiated var. appears to be not uncommou both in 

 Enofland and Scotland. 



3. C. Cijdnus, Li. (corn Blue-hotlle); scales of the involucre ser- 

 rated, leaves linear-entire the lowermost toothed. E. Bot. t. 217 . 



Corn-fields, frequent. FL July, Aug. ©. — 2 — 3 feet high, covered 

 vi'ith a loose, cottony down, especially on the stems and under-side of 

 the leaves. Florets of the disk small, ))urple ; of the rai/ few, larger, 

 bright blue, spreading. Scales of the involucre greenish, their margins 

 brown. 



4. C. Scabiosa, L. {^greater Knapweed); scales of the involucre 

 ciliated ovate downy, leaves roughisb pinnatifid, segments lanceo- 

 late acute. E. Bot. t. 56. 



Barren pastures, corn-fields, and road-sides. Fl. July, Aug. 1/! . — 

 2 — 3 feet high, erect, much branched. Involucres globose, very large, 

 their scales cottony, almost black, the fringe pale. 



5. C. Isndrdi, L. (Jersey Star-thistle); scales of the involucre 

 with palmated spines, leaves somewhat lyrateand scabrous tooth- 

 ed slightly amplexicaul, flowers terminal solitary with one or 

 more leaves at the base, E. Bot. t. 223G. 



Pastures in Jersey and Guernsey. Fl. July, Aug. 1^. 



6. C. Calcitraj)a, L. (^common Star-thistle); flowers mostly ses- 

 sile lateral, scales of the involucre spinulose at the base, ending 

 in a long broad spine, stem divaricated, leaves unequally pinna- 

 tifid spinuloso-dentate. E. Bot. t. 125. 



Gravelly, sandy and waste places, in the middle and S. of England ; 

 especially near the sea. Fl. July, Aug. 0. — Fioivers purple. — The 

 specific name is derived from the English word, Caltrops, (an instrument 

 of war with long points), latinized. 



7. C.*solstitidHs, L. (yellow Star-thistle, St Barnahy'' s-thistle); 

 flowers terminal solitary scales of the involucre palmato-spinose 

 at the base, ending in a long slender spine, stem winged from 

 the decurrent bases of the lanceolate unarmed leaves, radical 

 leaves lyrato-pinnatifid. E. Bot. t. 243. 



Occasionally seen in fields and waste places, princii)ally in the E. and 



S. of England, and near Dublin. Fl. July — Sept. Flowers yellow, 



as are the slender, needle-like spines of the involucre. 



