or wavy-margined leaves, and one to many flower heads of yellow, 

 orange, red, pinkish, or sometimes white flowers. All of the indi- 

 vidual flowers of each head are set on a flat, naked, common base 

 (receptacle), and each has a strap-shaped (ligulate) corolla, which 

 is squared and five-toothed at the summit. The involucres are cylin- 

 drical or bell-shaped, with the principal bracts in one to three series, 

 the outer ones usually being smaller than the others. The "seeds" 

 (achenes) are columnar or cylindric, mostly 10-ribbed, not tapering 

 toward the apex but squared on top, and are crowned with long tufts 

 of fragile, stiffish, tawny, brownish or dull white bristles (pappus). 

 The hawkweeds are closely related to the hawkbeards (Crepis spp.), 

 and some of the species of the two genera are often confused. They 

 can be readily distinguished, however, since most of the hawkbeards 

 have toothed or deeply cleft leaves, their "seeds" are narrowed both 

 at the top and base, and the copious tufts of hairs crowning the 

 "seeds" are soft and white. In the hawkbeards the bracts of the 

 involucre are thickened at the base or on the midrib, and the foliage 

 is either hairless or densely woolly, whereas hawkweeds have un- 

 thickened bracts and the foliage tends to be rough-hairy. 



