II COMPOSITE 243 



S. erucsefolius has the habit of S. Jacohcea, but is 

 more pubescent. The achenes are all equally hairy. 



S. squalidus. — A Southern European species which 

 has become naturalised on old walls at Oxford and 

 elsewhere. The achenes all bear silky hairs. 



S. paludosus. — A native of the Fens in the eastern 

 counties. It has glabrous achenes. 



S. saracenicus. — A South European plant which has 

 become naturalised by river-sides and in moist meadows. 

 The achenes are glabrous. 



S. palustris. — Native in the Fens district, but very 

 rare. The achenes are glabrous, with strong ribs. 



S. campestris occurs on dry banks and chalk downs 

 in York, Lincoln, and southwards. The achenes are 

 downy, with faint ribs. 



DORONICTJM 



Disk flowers complete. Eay flowers female, without 

 any pollen brush on the stigma. Two species occur 

 in Britain, naturalised in plantations. Sometimes 

 glabrous, sometimes hairy, and generally glandular 

 towards the summit. 



D. Pardalianches. — The ray flowers have rudiments 

 of stamens, and are as richly supplied with honey as the 

 disk flowers. A native of Central and Southern Europe. 



BiDENS 



Ray flowers sometimes absent ; when present, with- 

 out either stamens or pistil. The achenes terminate in 

 a few (2-5) stifi" awns, covered with reflexed prickles. 

 The generic name was suggested by the two stifi" awns 

 of some species. We have two species : one, B. cernua, 

 with undivided leaves, while in B. tripartita they are 

 deeply cut into 3-5 segments. They grow in watery 

 places, and are both nearly glabrous. 



B. cernua. — The ray florets are sometimes wanting. 

 The achenes have 2-3, rarely 4 awns. 



