COMPOSITAE (COxMPOSlTE FAMILY) 837 



2. V. virglnica L. Stem narrowly or interruptedly winged, downy-pubescent 

 like the lower surface of the ovate-lanceolate feather-veined alternate leaves 

 heads in compound corymbs ; receptacle convex ; flowers white; rays 3-4 ovar- 

 achenes winged. — Dry soil, Pa. to Kan., and south w. Aug. 



* * 



Heads broader^ solitary or few. 



3. V. helianthoides Michx. Perennial ; stem hairy, 1 ni. or less high widely 

 winged by the decurrence of the ovate to ovate-lanceolate sessile alternate leaves 

 which are rough above and soft-hairy beneath ; involucre appre.ssed ; rays 8-15* 

 pistillate or neutral, usually sterile; achenes winged, tipped with 2 fragile awns. — 

 Prairies and copses, O. to la., south w. and southwestw. June, ,l\Ay. 



4. V. ENCELioiDES (Cav.) B. «& H., var. exauricciAta Robinson & Green- 

 man. Annual, branching, 3-6 dm. high, cinereous; leaves alternate, ovate or 

 cordate to deltoid-lanceolate, the petioles destitute of the wings or auricles 

 (characteristic of the typical more southern form) ; involucral bracts lineai; 

 equal, foliaceous, spreading ; rays numerous, fertile. — Kan. to Tex., and westw. • 

 adventive by roads, w. Mo.; also casual northeastw., e.g. in s. Me. {Parlin). ' 



54. C0RE6pSIS L. TicKSEED 



Heads many-flowered, radiate ; rays mostly 8, neutral, rarely wanting. In- 

 volucre double ; each series of about 8 bracts, the outer foliaceous and somewhat 

 spreading ; the inner broader and appressed, nearly membranaceous. Receptacle 

 flat, with membranaceous chaff deciduous with the fruit. Achenes flat, ol)Com- 

 pressed (i.e. flattened parallel with the bracts of the involucre), often winged, 

 not narrowed at the top, 2-toothed or 2-awned, or sometimes naked at the sum- 

 mit ; the awns not barbed downwardly. — Herbs, generally with opposite leaves 

 and yellow or party-colored (rarely purple) rays. Too near the last section of 

 Bidens, but generally well distinguished as a genus. (Name from Kbpis, a bug, 

 and 3f IS, appearance ; from the form of the achene.) 



§ 1. Style-tips truncate or nearly so ; outer involucre small and short ; rays rose- 

 color oryelloio, with brown base; pappus an obscure border or none. 



1. C. rbsea Nutt. Perennial; stem branching, leafy, smooth, 2-6 dm. high; 

 leaves linear, entire; heads small, somewhat corymbed, on short peduncles; 

 rays rose-color, 3-toothed ; achenes oblong, wingless. — Sandy grassy swamps 

 and shores, e. Mass, to N. J., and south w. July-Sept. 



2. C. tinct6ria Nutt. Annual, glabrous, often 1 m. high; leaves 1-2-pin- 

 nately divided, the lobes lanceolate to linear ; achenes oblong, wingless ; rays 

 yelloio, with more or less of crimson-brown. — Minn, to Tex., etc.; common in 

 cultivation ; often escaping to roadsides, etc., eastw. 



§2. Style-tips abruptly cuspidate^ hispid; involucres nearly equal; achenes 

 roundish, winged, incurved, often papillose and with a callus inside at base 

 and apex; pappus 2 small teeth or none ; rays mostly yellow and palmately 

 lobed; perennials, with long-pedunculate heads ; lower leaves petiolate. 



* Wings of achene broad, thin, spreading. 



3. C. lanceolata L. Smooth or hairy, 3-6 dm. high, tufted, branched only 

 at the base ; leaves all entire (the lower rarely with a pair of small lateral lobes), 

 lanceolate, the lowest oblanceolate or spatulate; outer bracts ovate-lanctolate. 

 — Rich or damp soil, Ont. and Mich, to Va., Mo., and southw.; also cultivated 

 on account of its showy heads, and sometimes escaping eastw. May-July. 



Var. vill6sa Michx. Hirsute below, the hirsute or villous leaves ratlier 

 broader. (C. crassifolia Ait.) —111. and Mo. to Fla. 



4. C. grandiflbra Hogg. Mostly glabrous ; lower leaves lanceolate and spatu- 

 late, entire, the upper -^-'^-parted, with lanceolate to linear and sometiines "J— 3- 

 parted lobes; heads as in the preceding or larger. — Damp soil, Mo. and e. 

 Kan. to Tex. and Ga. May-July. 



