COREOPSIS— CREPIS 267 



d. Leaves sessile or nearly so, the teeth spiny- 

 pointed C. atractyloides 

 b. Leaves petioleel, the teeth not spiny-tipped 



(1) Heads 10-25-flowered 



(a) Leaves 2-4 cm. long; involucral bracts 



erect, not spreading C. Wrightii 



(b) Leaves 5-10 mm. long; involucral bracts 



spreading and reflexed C. microphyllus 



(2) Heads 30-50-flowered 



'(a) Heads drooping C. grandiflorus 



(b) Heads erect C. dmbigens 

 2. Leaves lance-oblong to linear, sessile ; heads 40- 



50-flowered C. ImifoUus 



Coreopsis Linne 1753 Tickseed 

 (Gr. koris, tick, opsis, look, from the form of the achene) 

 Heads with yellow to brown neutral ray-flowers, disk-flowers yellow, 

 perfect, achenes flat, oblong to rounded, often winged, pappus of 2 short 

 teeth or none ; receptacle flat, 'with chaff, involucre hemispheric, the bracts 

 in 2 distinct rows, united at the base, the outer row usually narrower and 

 shorter ; heads solitary or in corymbs ; leaves opposite or alternate, entire 

 to pinnately-divided ; annual or perennial. 



1 . Rays brown at the base or brown all over ; leaves 



1-2-pinnately divided into linear segments C. tinctoria 



2. Rays bright yellow ; leaves spatulate or oblong, 



entire C. lanceoldta 



Crassina Scepin 1758 Zinnia 

 (Named for Crassus, an Italian botanist) 

 Heads with yellow or yellowish pistillate rays, becoming papery and 

 persistent, disk-flowers yellow, perfect, achenes flattened, usually wingless, 

 pappus of 2-4 erect awns ; receptacle conic, with chaff, involucre bell-shaped 

 to cylindric, the bracts papery, imbricated in several rows ; heads solitary on 

 the branches ; leaves opposite, entire, sessile ; annual or perennial. 

 Stems 6-12 in. high; leaves linear or lance-linear, 1-3 



cm. long; rays 4-5, 10-16 mm. long C. grandiMra 



Crepis Linne 1753 Hawksbeard 

 (Gr. krepis, sandal, perhaps from the basal leaves) 

 PI. 37, fig. 7. 

 Heads of strap-shaped yellow or orange perfect flowers, achenes linear- 

 oblong, 10-20-ribbed, not beaked, pappus of hair-like white bristles; re- 

 ceptacle flat, without chaff, involucre ovoid to cylindric, the main bracts 



