222 COMPOSITE. (COMPOSITE FAMILY.) 



late, pointed, coarsely toothed, mostly stalked; outer leafy involucre much longer 

 than the head, ciliate below ; rays none ; achenia wedge-obovate, 2-awned, the mar- 

 gins dilate with upward bristles, except near the summit. Moist waste places, a 

 common coarse weed, very troublesome ; the achenia, as in the other species, 

 adhering by their retrorsely barbed awns to the dress, and to the fleece of ani- 

 mals. July -Sept. In Western New York, Dr. Sartwcll has found it with 

 one or two small rays ! 



2. B. coiiiifila, Muhl. ( SWAMP BEGGAR-TICKS.) Smooth (l-2 

 high) ; leaves lanceolate or oblong-lanceolate, pointed, sharply serrate, tapering 

 into margined petioles which are slightly united at the base ; the lower often 3- 

 divided; the lateral divisions united at the base and decurrent on the petiole; scales of 

 the outer involucre longer than the head, mostly obtuse, scarcely ciliate ; rays 

 none; achenia narrowly wedge-form, 3- (2-4-) owned, and with downwardly barbed 

 margins. (B. tripartita, Bigel.) A thin-leaved more petioled form is B. petio- 

 lata, Nutt. Wet grounds, New York to Illinois, and southward. 



3. B. coniiia, L. (BUR-MARIGOLD.) Nearly smooth (5' -10' high); 

 leaves all undivided, lanceolate, unequally serrate, scarcely connate; heads nodding, 

 with or without (light yellow) rays; outer involucre longer than the head ; ache- 

 nia wedge-obovate, 4-awned, the margins downwardly barbed. Wet places, 

 New England to Wisconsin, and northward. Rays, when present, smaller than 

 in the next, the leaves irregularly toothed, and the outer involucre more leaf- 

 like. (Eu.) 



4. B. chrysanthemoides, Michx. (BUR-MARIGOLD.) Smooth, 

 erect or reclining at the base (6' -30' high) ; leaves lanceolate, tapering at both 

 ends, more or less connate, regularly serrate ; heads erect or nodding, conspicuously 

 radiate; outer involucre mostly shorter than the golden-yellow (!' long) rays; 

 achenia wedge-shaped, with almost prickly downwardly barbed margins ; awns 

 2, 3, or 4. Swamps ; common. Aug. - Oct. Probably runs into No. 3. 



# * Achenia linear-4-sided, slender, tapering at the summit. 



5. B. Beckii, Torr. (WATER MARIGOLD.) Aquatic, smooth; stems 

 long and slender, bearing crowded immersed leaves many times dissected into fine 

 capillary divisions ; the few emerging leaves lanceolate, slightly connate, toothed ; 

 heads single, short-peduncled ; involucre much shorter than the showy (golden-yel- 

 low) rays; achenia linear, thickish, smooth (' long), bearing 4-6 stout diver- 

 gent awns which are 1' long, barbed only towards the apex. 1J. Ponds and 

 slow deep streams, Massachusetts (rare) to Illinois and Wisconsin. 



6. B. bipinnata, L. (SPANISH NEEDLES.) Smooth, branched (1- 

 4 high) ; leaves 1 - 3-pinnately parted, petioled; leajlets ovate-lanceolate, mostly 

 wedge-shaped at the base ; heads small, on slender peduncles ; outer involucre of 

 linear scales, nearly as long as the short pale yellow rays ; achenia long and slender, 

 4-grooved and angled, nearly smooth, 3 - 4-awned. (J) Dry soil, Connecticut 

 to Illinois, and southward. 



43. VEIIBESINA, L. CROWNBEARD. 



Heads several - many-flowered ; the rays pistillate, few, or sometimes none. 

 Scales of the erect involucre few, imbricated in 2 or more rows. Receptacle 



