BIDENS 281 



extreme state is markedly different from the short-rayed form in which 

 the ray florets are closely contiguous, intermediate forms are found, 

 so that it can be scarcely called a good variety. It may be remarked 

 liowever that all the plants in one station remain pretty constant, but 

 that the permanence of the extreme form has not been tested by 

 cultivation. Specimens from Wytham were distributed by me through 

 the Bot. Exch. Club in 1887. The beautiful golden yellow flowers 

 contrast well with the sombre purple of Mentha aquatica, a plant 

 frequently associated with I. dysenterica. Both the Scarlet Admiral and 

 Common Blue Butterflies are very fond of this species, which occurs 

 in all the bordering counties. 



P. viilg'aris, Gaertn. 1. c. ISmall Fledbane. 



P. Pidicaria, Karst. Inula PuUcaria, Linn. Sp. PL 882 (1753). I. uligi- 

 nosa, Sibth. Fl. Oxon. 256 (1794). Conyza minima, Gerard, 390. 



Top. Bot. 259. Syme, E. B. v. 103, t. 771. Nyman, 394. Fl. Oxf. 169. 

 Native. Inundatal. Margins of ponds. Very rare. A. July- August. 

 First record. Inula Pidicaria. Plentiful in the parishes of Burghfield 

 and Mortimer, Dr. Beeke in lit. 1799. 



4. Kennet. Burghfield. Mortimer, Dr. Beeke. (I have not seen 



it here.) 



5. Loddon. Bulmarsh Heath, Budge in Herb. Brit. Mas. 1800. Near 



Wellington College (^perhaps in Hants). Wokingham, Pennu. 

 Between Bray and Holyport. Near Sandford Mill. 

 P. vidgaris, which is one of our rarer plants, is not recorded for Bucks 

 or Gloucestershire ; it appears to be a decreasing species. 



[Xanthium Stkumakium, Linn. Sp. PI. 98^, is recorded as a casvial plant for 

 Surrey and Hants, and X. spinosum has been seen by Mr. W. Clarke in 



wnts.] 



BIDENS, Linn. Gen. n. 840 (Tournefort, Inst. t. 262;. 



B. cernua, Linn. Sp. PI. 832 (1753). Nodding Bin- Marigold. 



Verbesifia, Gesner. Bidens, folio non dissecta, Caesalp. 



Top. Bot. 248. Syme, E. B. iv. 93, t. 763. Nyman, 348. Fl. Oxf. 156. 

 Native. Paludal. Pond-sides and wet places. Bare north of Beading, 

 and possibly absent from the Isis and Ock districts. Common in 

 the Loddon district. A. or B. June-September. 

 First record. Wash Water, Russell's Cat. 1839. 



[1. Isis. Mr. Boswell records it for Eynsham in Oxfordshire ; it may 

 be found on the Berkshire side of the stream, but I have not 

 yet met with it.] 

 2. Ock. Marked as having been seen by Mr. F. Walker in either 

 Marcham, Appleton, or Tubney, but I have not been able to 

 confirm it. 



