3 1 4 COMPO SIT.E. [Bidens. 



32. BIDENS. Zinn. 



Achenium exalatum, subcompressum. Aristw pappi retrorsum hispida?, 2-5, persistentes. 

 — Herba; rarins Frutices, per totam zonem cBquinoctiakm et meridionalem divulgatcB, follis 

 integris vel varie sectisy rafnisque oppositis ; capitulis terminalihus soUtariis vel corymbosis, 

 discoideis vel radiatis, radio luteo vel albo ; involucris polgphyllis, biscrialibus, foliolis 

 exterioribus patentibus ; rachide jo/awa. Less. 



1. B. cernua ; floribus subradiatis cernuis, involucri foliolis exterioribus flore longioribus, 

 foliis lanceolatis subconnatis serratis. — Linn, — Engl, Bot, t 399. Pursh^ FL Am. v, 2. p. 

 566. — /3, minima. 



Hab. Througliout Cauada ; from Lake Huron, (Z)?-. Todd), to the Saskatchawan ; Dr. Richardson. 

 Drummond. — /3, Island of Orleans, In the St. Lawrence. Mrs. Sheppard.~Jn this and the following, the 

 stems are often partially clothed with short, coarse, and thick white hairs. 



w 



2. B, chrysanthemoides ; floribus radiatis cernuis, radio involucro subsequali triple 

 longiore, foliis oblongis utrinque attenuatis dentatis basi connatis. Ph, — Mich, Am, v. 2, p, 

 136. Pursh, FL Am, v. 2. p, 566. Elliott, Carol, v. 2, p, 429. 



Hab. Fort Vancouver (Douglas) and Straits of de Fuca, on the North -West coast. Dr. Scouler.— 

 These specimens are larger, and the leaves broader than in B, cernua ; but I do not think that the two 

 species are distinguished by any decided characters. 



3. B. frondosa ; floribus discoideis, involucro foliolis exterioribus foliaceis flore multo 

 longioribus, foliis ternatis (inferioribus quandoque pinnatis) foliolis lanceolatis serratis. — 

 Linn, — Mich, Am. v, 2. p, 136. Pursh, FL Am. v, 2. p. 566. EllioU, CaroL v. 2, p. 431. 



Hab. Canada, {Mrs, Percival), to the Saskatchawan. Dr. Richardson. Drummond, 



4. B.connata; floribus discoideis, involucri foliolis exterioribus flore sublon^noribus, 

 foliis tripartitis (inferioribus quandoque pinnatis) foliolis lanceolatis serratis. — Willd, Sp, PL 

 V. 3. p. 1718. Pursh, Fl. Am, v, 2. p, 566. Elliott, CaroL v, 2. p, 430. 



Hab. Woodfield, near Quebec, {Mrs. Sheppard)^ to Cumberland House, on the Saskatchawan. Dru7n- 

 mond.— In my specimens, both of this and the preceding, the leaves are all temate, and they only differ in the 

 relative length of the outer leaflets of the involucre. 



4 



5. B,pilosa; floribus discoideis, involucri foliolis exterioribus longitudine interiorum, 

 foliis inferioribus pinnatis, superioribus ternatis, foliolis oblongis, terminali lanceolato 

 reliquis duplo longiore. Willd,~~Linn, Sp, PL p, 1166. Pursh, FL Am. v. 2. p. 566. Elliott, 

 CaroL v, 2.^. 431. 



Hab. La Grande Chaudiere. Pursh. 



Subtrib. V. Helenie^. Capitula nunquam dioica ; si heterogama, floribus ? vel neutris 

 uniserialibus in ambitu corollasque lingulatas gerentibus, reliquis ^ , Pappus multipale- 

 aceus, perfectus, regularis, aut cequalis aut subaqualis, ubi tunc rami sttjli ^ apice 

 truncati sunt, palejs integris sive plumoso-fimbriatis seu pinnatisectis. Anthers ecaudatcB, 

 Achenium erostre, Involucrum polyphyllum. Less, 



1. Gaillardie.e. Nutt Pappi paleis integris, rachide ebracteolata aut tantum margine 

 bracteolata. Less, 



