Addisonia 65 



(Plate 113) 



COREOPSIS LEAVENWORTHH 

 Leavenworth's Tickseed 



Native oj peninsular Florida 

 Family Carduacsa^ Thisti,© Family 



Coreopsis Leavenworthii T. & G. Fl. N. Am, 2: 346. 1842. 



An annual plant, five feet tall or less, bright green, often with a 

 short-jointed caudex at the base. The stems are relatively slender, 

 simple or sparingly branched and erect, or much branched near 

 the base and more or less diffuse; the branches are glabrous, 

 terete or longitudinally ridged when dry, and usually branched 

 throughout. The leaves are opposite, glabrous, the lower ones 

 with linear or narrowly spatulate blades, which are entire, or deeply 

 pinnatifid with one to three pairs of narrow lateral lobes; the 

 upper leaves have entire blades narrower than those of the lower 

 ones. The bracts subtending the peduncles in the inflorescence 

 are filiform or nearly so. The showy heads are slender-peduncled 

 and erect. The involucre is double, hemispheric in anthesis, and 

 persistent. The outer bracts are lanceolate-subulate to lanceolate 

 or ovate-lanceolate, a twelfth of an inch long or less; the inner 

 bracts are ovate, olDtuse, thrice as long as the outer ones or more, 

 somewhat fleshy, and glabrous. The copiously pitted receptacle 

 is convex or sometimes nearly hemispheric, bearing narrowly hnear 

 bractlets. The disk is dark-brown or nearly black, about a quarter 

 of an inch wide or less. The disk-corollas are numerous, narrowly 

 funnelform, and less than one sixth of an inch long, with broadly 

 ovate lobes. The stamens are slightly exserted, with ovate tips, the 

 anthers longer than the free portion of the filaments. The ray is 

 composed of about 8 flowers; the ligules are bright yellow, spread- 

 ing, with blades varying from ovate to cuneate, about a half inch 

 long, and obtusely three-lobed at the apex. The pappus is two 

 upwardly barbed subulate awns. The achenes are roundish in 

 outline, less than one sixth of an inch long, over all, the body ellip- 

 soid, black, minutely punctate-cancellate, and usually sparingly 

 granular-dotted. The wings are thin and translucent, each about 

 as wide as the diameter of the achene-body, very finely laterally 

 striate, extending above the top of the achene-body; in the sinus 

 thus formed the two pappus-awns, in length about equal to the 

 diameter of the achene-body, arise. 



The genus Coreopsis, well known to plant lovers through several 

 species almost universally cultivated in gardens, is represented by 

 not less than twenty-four native ones in the southern states east 

 of the Mississippi River. As many as fourteen species grow natur- 

 ally in Florida. Some of these found their way to Linnaeus before 



