582 



CICHORIACEAE. 



[Vol. III. 



Crepis intermedia A. 



Gray. Small-flowered Gray Hawksbeard. 

 (Fig- 3559-) 



Crepis intermedia A. Gray, Syn. Fl. i: Part 2, 432. 1884. 

 Perennial, cinereous-puberulent or scurfy; stem 

 rather slender, 1-3-leaved, i-2 high, naked and 

 branched above. Basal leaves lanceolate or oblong- 

 lanceolate, laciniate-pinnatifid, long acuminate at the 

 apex, narrowed at the base, 4 / -6 / long; stem leaves 

 lanceolate, sessile, less divided; heads several, 6 // -q // 

 broad, 5-8-flowered; involucre oblong-campanulate, its 

 principal bracts 5-8, lanceolate or linear-oblong, canes- 

 cent, acutish, somewhat keeled by the thickened midrib 

 when old, the outer ones few and short; achenes ob- 

 long, narrowed above, not beaked, strongly 10-ribbed. 



In dry soil, western Nebraska (according: to Williams) 

 and Colorado to California and British Columbia. May- 

 Sept. 



8. Crepis occidentalis Nutt. Large-flow- 

 ered Gray Hawksbeard. (Fig. 3560.) 

 Crepis occidentalis Nutt. Journ. Acad. Phil. 7: 29. 1834. 



Perennial, scurfy and canescent, sometimes also hir- 

 sute; stem rather stout, leaf)*, branched, 6'- 18' high. 

 Leaves oblong-lanceolate or oblong in outline, lacini- 

 ate-pinnatifid, acute or acuminate, the lower and basal 

 ones 6 / -io' long, narrowed into petioles, the upper 

 sessile and slightly clasping; heads few or several, 

 corymbose, stout-peduncled, about i / broad, 10-30- 

 flowered; involucre oblong-campanulate, canescent, 

 its principal bracts 9-24, linear, acute; achenes oblong, 

 sharply 10-ribbed, glabrous. 



Plains, western Nebraska (according to Gray) and Colo- 

 rado to California, north to the Northwest Territory and British Columbia 



May-July. 



21. KIERACIUM L. Sp. PI. 799. 1753. 

 Perennial hispid scabrous glandular or glabrous herbs, with alternate or basal leaves, 

 and small middle sized or large, solitary corymbose or paniculate heads of yellow orange or 

 red flowers. Involucre cylindric, campanulate, or nearly hemispheric, its principal bracts 

 in 1-3 series, the outer either regularly and gradually smaller or abruptly much smaller, 

 none of them much thickened at the base after flowering. Receptacle flat, naked or short- 

 fimbrillate. Rays truncate and 5-toothed at the apex. Anthers sagittate at the base. Style- 

 branches slender. Achenes oblong, columnar, or fusiform, not beaked, 10-15-ribbed, terete 

 or 4-5-angled. Pappus copious, or 1-2 rows of simple rather stiff persistent brown or brown- 

 ish bristles. [Greek, hawk.] 



Not fewer than 300 species, natives of the north temperate zone and the Andes of South Amer- 

 ica. Besides the following, some 15 others occur in western North America. Known as Hawkweed, 

 Hawk-bit, or Speerhawk. 



X- Flowering stem leafless, or with 1-5 leaves. 

 (a) Stem scapose, with a single head onl}-; introduced. 1. H. Pilosella. 

 (b) Heads corymbose or paniculate. 

 Leaves coarsely dentate; introduced species. 



Leaves cordate or subcordate. 2. H.miirornm. 



Leaves narrowed at both ends. 3. H. vulgatum. 



Leaves denticulate or entire 



Leaves mostly entire, spatulate to oblong; heads corymbose; introduced species. 



Heads 8" -1 2" broad; flowers red or orange. 4. H. aurantiacum. 



Heads $"-<)" broad; flowers yellow. 



Glaucous, slightly hispid. 5. H. praealtum. 



Densely hirsute. 6. H. pratense. 



Leaves, at least some of them, denticulate, mostly obovate or oval; heads corymbose-paniculate; 

 natives. 

 Principal bracts of the involucre glabrous, or nearly so. 



Stem glabrous, or nearly so; leaves usually purple-veined. 7. H. venosnm. 



Stem pilose below; leaves green. 8. H. Marianum. 



Involucre and peduncles densely hirsute and glandular. 9 H. Greenii. 



'.'.- -X- Flowering stem abundantly leafy, at least below. 

 (a) Principal bracts of the involucre in 2-4 series; heads corymbose. 

 Leaves sessile, not clasping; involucre glabrous. > 10. H. umbellalum. 



Leaves, at least the upper, clasping: involucre pubescent. 11. H. Canadense. 



