222 COMPOSITE. (COMPOSITE FAMILY.) 



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

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

 gins ciliate 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. Sartwell has found it with 

 one or two small rays ! 



2. B. toiniala, Muhl. ( SWAMP BEGGAR-TICKS.) Smooth (1-2 C 

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

 into margined petioles which are slightly united at the base ; the lower ojlen 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-) awned, and with downwardly barbed 

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

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



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

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

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

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

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

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

 like. (Eu.) 



4. B. clirysanthemoides, 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; sterna 

 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 shoj-ter than the sJioivy '(yolden-yel- 

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

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

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



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

 4 high) ; leaves 1 - 3-pinnately parted, petioled; leaflets ovate-lanccolaie, 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. () Dry soil, Connecticut 

 to Illinois, and southward. 



43. VERBESINA, 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 



