COMPOSITE. (COMPOSITE FAMILY.) 
231 
setts, to New Jersey, rare. Aug.— Plant 8*-18' high, with small 
heads. 
C. tinct6ria, Nutt., a native of the Southwestern States, with yel¬ 
low rays brown-purple towards the base, is everywhere common in 
gardens. 
C. auriculata, L., is to be sought in Western Pennsylvania. 
37. BIDENS, L. Burr Marigold. 
Heads many-flowered ; the rays 3 — 8, neutral, frequently incon¬ 
spicuous or entirely wanting. Involucre double, the outer com¬ 
monly large and foliaceous. Receptacle flattish, the chaff decid¬ 
uous with the fruit. Achenia flattened parallel with the scales of 
the involucre, or slender and 4-sided, crowned with 2 or more 
rigid and persistent awns which are downwardly barbed. — An¬ 
nual or perennial herbs, with opposite various leaves, and mostly 
yellow flowers. (Name the Latin bidens, from the two teeth or 
awns of the fruit.) 
* Achenia flat, not tapering at the summit. (All annuals ?) 
1. B. fronddsa, L. (Common Beggar-ticks.) Smooth or 
rather hairy, tall (2°-6° high) and branching; leaves 3-5 -divided; 
the leaflets lanceolate, pointed, coarsely toothed, mostly stalked; outer 
leafy involucre much longer than the head, ciliate below ; rays none; 
achenia wedge-obovate, 2-awncd, the margins ciliate with upward bris¬ 
tles, except near the summit. — Moist waste places, a common coarse 
weed, very troublesome; the achenia, as in the other species, adher¬ 
ing by their retrorsely barbed awns to the dress, and to the fleece of 
animals. July — Sept. 
2. B. connata, Muhl. (Swamp Beggar-ticks.) Smooth 
(1° -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; 
narrowly wedge-form , 3- (2 - 4-) awned , and with downwar y ar e 
margins. (B. tripartita, Bigel.) — Wet grounds, common, especially 
from New York westward. 
3. B. cernua, L. (Nodding Burk-Marigold.) Nearly 
smooth, low; leaves all undivided, lanceolate, unequally serrate, scarce¬ 
ly connate ; heads nodding, with or without (light yellow) rays, oul ® 
involucre longer than the head; achenia wedge-obovate, 4-awned, 
the margins downwardly barbed. — Swamps and ditches, Massachu¬ 
setts to Michigan northward. — Rays, when present, sm er t an 1 
the next, the leaves irregularly toothed, and the outer in' o ucre 
more leaf-like. 
