BIDENS. ^AOmLlEA. 185 



minal corymbose, rays much exceeding the dwk.—Imula Sm. — 

 Creeping,. floccose. St. 12 — 18 in. ygh,leafy. Heads larger 

 than in Sp. 1, bright yellow ; fr. ansular. Outer pappus cup- 

 like, crenulate.— Damp places. P. VUI. IX. E. S. I. 



Tribe III. Senecionece. 



Style of perfect fl. cylindrical ; branches long, linear, ending 

 in a bunch of hairs or sometimes extending beyond the hairs 

 into a short cone or iippeadage. Stigmatic lines broad and 

 prominent and extending as far as the hairs. 



Section 1. ITELXrliVTjSJS:^'. Heads discoid with all the 

 fl. similar and perfect ,• or rarely radiant with dissimilai flower.s. 

 Anth. without appendages. Receptacle scaly throughout or 

 only near the margin. Cor. of the perfect fl. with (iickened 

 lobes. Pappus of a few bristles in om- plants. 



II. (24.) Wjhess Idtm. 



1. B. tripattita, (L.) ; /. talked S-partite, segmraits lanceolate 

 sen-ate, fr. obovate-cuneate usually with 2 bristles. — JR. xvi. 941. 

 — St. 1 — 3 feet high, with opposite branches. L. narrowed into 

 winged footstalks, sometimes 'undivided, sOm^imjea pinnate-5- 

 fld. Heads terminal, Solitary, slightly diooping. Fl. brownish 

 yellow. — Sometimes radiant S-toothed marginal fl. ai-e found. — 

 Marshy places. A. Mil. IX. E. S. I. 



2. B. cer'mm (L.) ; I. sessile connate lanceolate imdivided' aei- 

 rate, fr. cuneate nSuaUy with 3- — 4 bristles. — H. xvi. 941. — St. 

 1 — 3 feet high, with opposite, hranches. L. simple, narrowed 

 below but not stalked; Heads terminal, solitary, drooping. Fl. 

 brownish yellow. — Sometimes radiant marginal fl. are fpund.^— 

 Watery places. A. VIH. IX. E. a 1. 



Section 2. ANTHEMIDE^, Heads usually radiant, fl. of 

 ray fern, or wholly barren. Anth. without appendages. Branches 

 of the style truncate, bearded, very rarely ending in a cone. 

 Pappus often wanting or crownUke^ rarely formed of scales or 

 slender hairs. 



12. (22.), Achille'a Luin^ Yarrow. 



1. A. Pta/mica (L.) ; I. shining linear-lanceolate attenuate 

 acide glabrous smooth uniformly andflnety serrate, teeth adpressed 

 mucronate minutely scafcrous at the margin, ray 8 — 12-flowered 

 equalling the involuerfej corymb compound; — M. xvi. 1024.— St. 

 about 2 feet high, slightly branched above, erect, leafy, angular, 



