388 COMPOSITE. Bidens. 



twice the length of the disk. Achenia nearly smooth on the sides : awns rather slender, the 

 intermediate ones shorter than the others. 



Low wet places ; Penn-Yan {Dr. Sartwell). August - September. This species is not 

 rare in the State of New-Jersey. 



4. Bidens chrysanthemoides, Michx. Large-flowered Bur-marigold. 



Leaves all undivided, lanceolate, more or less connate, equally and rather remotely serrate ; 

 heads with large rays ; scales of the exterior involucre somewhat longer than the disk and 

 shorter than the rays, ciUate-serrulate, particularly below the middle ; interior scales mem- 

 branaceous, with a broad colored margin ; achenia cuneate, with the margin hispid downward ; 

 awns 2 - 4.— Michc. fl. 2. p. 136 ; Pursh,fi. 2. p. 566 ; Ell. sk. 2. p. 430 ; Bigel.fl. Bost. 

 p. 294 ; Torr. compend. p. 311 ; Beck, hot. p. 207 ; Darlingt. fl, Cest. p. 485 ; DC. prodr. 

 5. p. 595 ; Torr. ^ Gr. fl. N. Am. 2. p. 352. 



Annual ? Stem 1-2 feet high, erect or reclined at the base, smooth, branching. Leaves 

 3-6 inches long, varying from broadly to narrow lanceolate, tapering to each end, sessile. 

 Heads erect or somewhat nodding. Rays 8 - 10, obovate-oblong, bright orange-yellow, 

 variable in length, but usually about twice as long as the exterior involucre. Awns of the 

 achenia two, with one or two shorter intermediate ones. 



Swamps and margins of ponds ; common. August - November. Cattle seem to be fond 

 of this plant. The flowers are very conspicuous late in the season, in wet meadows. 



5. Bidens Beckii, Torr. (Plate LXVIII.) Water Marigold. 



Stem simple, sparingly branched ; leaves mostly submersed, dichotomously divided into 

 numerous capillary segments ; the emersed ones few, lanceolate, serrate or pinnatifidly laci- 

 niate ; heads solitary, erect, radiate, terminal ; scales of the exterior involucre few, oval or 

 oblong, shorter than the interior and somewhat resembling them, several times shorter than 

 the rays ; achenia smooth, 4 - 6-awned. — Torr. in Spreng. neue entd. 2. p. 135, and syst. 

 3. p. 455 ; Torr. compend. p. 312 ; Beck, hot. p. 207 ; DC. prodr. 5. p. 595 ; Torr. ^ Gr. 

 fl. N. Am. 2. p. 353. 



Perennial. Stem 2-6 feet or more in length, sometimes producing short branches from 

 the axils of the upper leaves, rather stout. Submersed leaves appearing verticillate, the 

 primary divisions extending to the base, the segments very numerous and as fine as horse- 

 hair ; the lowest emersed ones pinnatifid ; uppermost undivided, sharply serrate. Heads on 

 short terminal peduncles. Scales of the inner involucre lanceolate, acute. Rays golden yellow. 

 Achenia narrowly oblong. Awns commonly 6, unequal, hispid above, smooth below. 



In lakes, ponds and slow-flowing streams. First discovered in a pond near Schenectady, 

 by Dr. L. C. Beck. Schuyler's lake, and other waters in the western part of the State {Prof. 

 Gray and Prof. Aikin). Ponds near Augusta {Dr. Douglas). August. 



