Genus 69. 



THISTLE FAMILY. 



4S9 



I. Ximenesia encelioides Cav. Golden Crownbeard. Fig. 4491. 



Ximenesia encelioides Cav. Icon. 2: 60. pi. 178. 1793. 

 Verbesina encelioides A. Gray, Syn. Fl. 1 : Part 2, 288. 



Annual; stem densely puberulent, much branched, 

 l-2 high. Leaves deltoid-ovate or deltoid-lanceo- 

 late, thin, 2'-4' long, acuminate, acute or blunt at the 

 apex, coarsely dentate, or even laciniate, green and 

 minutely pubescent above, pale and densely canescent 

 beneath, all alternate, or the lowest opposite, nar- 

 rowed at the base into naked or wing-margined peti- 

 oles, which are often provided with dilated append- 

 ages at the base; heads several or numerous, 1/-2' 

 broad ; involucre hemispheric, about V high, its bracts 

 lanceolate, canescent; rays 12-15, bright golden yel- 

 low, 3-toothed ; achenes of the disk-like flowers obo- 

 vate, winged, pubescent, their pappus of 2 subulate 

 awns, those of the ray-flowers rugose, thickened, 

 often wingless. 



In moist soil, Kansas to Texas, Arizona and Mexico, 

 and occasional in waste grounds farther east. Also in 

 Florida and widely distributed in warm regions as a 

 weed. Summer. 



70. COREOPSIS L. Sp. PI. 907. 1753. 



Anual or perennial, mostly erect herbs, with opposite leaves, or the upper alternate, and 

 large long-peduncled heads of both tubular and radiate flowers, the rays yellow, or brown 

 at the base, or brown throughout, or pink. Involucre usually hemispheric, its bracts in 2 

 distinct series, all united at the base, those of the outer series commonly narrower and shorter 

 than the inner. Receptacle flat or slightly convex, chaffy, the chaff flat or concave. Ray- 

 flowers neutral. Disk-flowers perfect, fertile, their corollas with slender tube and broader 

 S-toothed limb. Anthers mostly entire at the base. Style-tips truncate or subulate. Achenes 

 flat, orbicular to oblong, winged or wingless. Pappus of 2 short teeth, or a mere coroniform 

 border, or none. [Greek, bug-like, referring to the achenes.] 



About 55 species, natives of America, South Africa and Australia, known as Tickseed. In 

 addition to the following, some 20 others occur in the southern and western United States. Type 

 species: Coreopsis lanceolata L. 



1. Style-tips acute or cuspidate; outer involucral bracts about as long as the inner (except in 



C. tripteris). 

 Leaves simple, or pinnately lobed ; achenes often with a callus on the incurved inner side. 

 Achenes with thin flat broad wings. 



Leaves mostly near the base of the stem, the heads long-peduncled. 

 Glabrous, or sparingly hairy below. 

 Pubescent or hirsute. 

 Stem leafy to near the shorter-peduncled heads. 



Pubescent or hirsute ; leaves entire or with a few lateral lobes. 



Glabrous or very nearly so ; leaves 1-2-pinnately parted into narrow segments. 



4. C. grandiflora. 

 Achenes with thick, involute narrow wings. 5. C. auricula a. 



Leaves palmately 3-cleft or divided ; achenes without callus. 



Leaves petioled. 3-divided into lanceolate segments, or the upper entire. 6. C. tripteris. 

 Leaves sessile. 



Leaves rigid, deeply 3-lobed above the base. 7. C. palmata. 



Leaves divided to the base. 



Leaf-segments entire ; disk-flowers yellow. 8. C. major. 



Leaf-segments 1-2-parted. 



Disk-flowers yellow; leaf-segments linear-filiform. 9. C.verticillata. 



Disk-flowers purple-brown ; leaf-segments 1 "-3" wide. 10. C. delphinifolia. 



2. Style-tips truncate or obtuse; outer involucral bracts much shorter than the inner. [Genus 



Calliopsis Reichb.] 

 Achenes broadly winged ; annual. n. C. cardaminefolia. 



Achenes wingless. 



Rays yellow with brownish bases ; annual with pinnately divided leaves. 12. C. tinctoria. 



Rays rose-pink, rarely white; perennial with linear entire leaves. 13. C. rosea. 



C. lanceolata. 

 C. crassifolia. 



3. C. pubescens. 



