896 CARDUACEAE 



and 1 cm. broad; bracts well imbricate; glandular green tips small, lanceolate. 

 Canons and meadows: Colo. Submont. Mont. S. 



23. M. spectabilis Greene. Biennial; stems several, 2-3 dm. high, glabrous 

 or nearly so; lower leaves oblanceolate, petioled, the upper linear and sessile; 

 involucres turbinate, about 1 cm. high and 12 mm. broad; bracts linear, acumi- 

 nate; tips almost as long as the chartaceous portion, glandular-puberulent; 

 ligules violet, 1 cm. long. Mountains: Colo. Mont. Au. 



24. M. cichoriacea Greene. Biennial; stem stout, 3-6 dm. high; leaves 

 pale green, glabrous, lanceolate, sessile, 3-5 cm. long, runcinate-dentate; invo- 

 lucres turbinate, about 7 mm. high and broad; bracts linear, acute; tips short, 

 glandular-puberulent; ligules about 6 mm. long, violet. Hills and mountains: 

 Colo. e Utah N.M. Ariz. Son Submont. Au. 



25. M. Fremontii Rydb. Biennial, with thick taproot; stems several, 4-5 

 dm. high; basal leaves oblanceolate, petioled, glandular-hispid and scabrous, 

 sharply dentate; upper leaves sessile, linear or lanceolate; heads over 1 cm. high; 

 bracts^linear-lanceolate, cinereous; ligules purple, 8-10 mm. long. River bottoms : 

 Colo. Jl. 



45. ERIGERON L. FLEABANE. 



Annual, biennial, or perennial herbs, caulescent or almost scapose. Leaves 

 alternate, entire, toothed, or lobed. Heads solitary, corymbose, or paniculate, 

 radiate or rarely discoid. Involucres hemispheric or saucer-shaped; bracts in 

 1-2, rarely 3 series, sub-equal or slightly imbricate; receptacle flat, naked. Ray- 

 flowers pistillate, white, pink, or purple, rarely ochroleucous or yellow, or want- 

 ing. Disk-flowers perfect with yellow corollas. Anthers entire and obtuse at 

 the base. Stigmas flattened, with mostly obtuse appendages. Achenes usually 

 flattened, 2-nerved, in a few species subterete and several-nerved. Pappus in a 

 single series of capillary scabrous bristles, or sometimes with a series of shorter 

 bristles outside. [Wyomingia A. Nels.] 



Bracts of the involucre in 1-2 series of almost equal length, not thickened on the back. 

 Rays inconspicuous, erect or ascending, usually involute and incurved, numerous; 

 often inside them a series of rayless pistillate flowers ; leaves entire. 



I. ACRES. 



Rays conspicuous, spreading, flat; no rayless pistillate flowers inside. 

 Plant without runners. 



Perennials with rootstocks or woody caudices. 



Leaves dissected or deeply cleft. III. COMPOSITI. 



Leaves entire or merely* toothed. 



Stems low, less than 2 dm. high, scapiform, usually bearing only one 



head; stem-leaves usually reduced. 

 Involucre and peduncles villous with many-celled hairs; bracts 



comparatively broad. II. UNIFLORT. 



Involucre and peduncles hirsute to glandular-puberulent or glabrate, 



not long-villous. IV. RADICATI. 



Stem leafy, 2-10 dm. high, if lower bearing several heads; stem-leaves 



ample. 

 Stems densely cespitose from a thick taproot; heads small, the 



disk rarely more than 1 cm. wide. 



Pappus double; stem hirsute. V. PUMILI. 



Pappus simple; stems strigose. VI. DECUMBENTES. 



Stems usually solitary from the ends of distinct (sometimes branched) 



rootstocks; heads large, the disk more than 1 cm. wide. 

 Bracts with loose tips; rays broad; pappus simple; lower leaves 



broadly oblanceolate, the upper often reduced. 

 Bracts villous. VII. ELATIORES. 



Bracts glandular-puberulent or glabrous. 



VIII. SALSUGINOSI. 

 Bracts appressed, except the very tips; rays narrow; pappus 



double; perennials with short rootstocks. 

 Upper stem-leaves ample, ovate to lanceolate, not much 

 smaller than the lower, which are more or less distinctly 

 3-nerved; peduncles usually short, ascending. 



IX. MACRANTHI. 



Upper stem-leaves reduced, linear-lanceolate; none of the 

 leaves 3-nerved; peduncles long and erect. 



X. GLABELLI. 



Annuals or biennials, or perennials by means of stolons and offsets. 

 Stem-leaves broad, cordate-clasping; perennials with offsets. 



XI. PHILADELPHICI. 



