COMPOSITAE. 367 



Leaves ciliate and sparsely pi- 

 lose. E. leibergii. 

 Stems tall, leafy. 



Ray-flowers narrow, 100-150. 



Leaves entire; ray-flowers violet. E. speciosus. 

 Leaves dentate; ray-flowers pink. E. philadelphicus. 

 Ray-flowers broader, 30-60. 



Cauline leaves half-clasping at base. E. howellii. 

 Cauline leaves sessile or short- 

 petioled. 

 Involucre sparsely pilose. E. amplifolius. 



Involucre minutely glandular. E. salsuginosus. 



Erigeron canadensis L. Annual, strictly erect, simple or with erect 

 branches, usually 30-100 cm. high, loosely hirsute throughout; leaves numer- 

 ous, linear, entire, or the lower spatulate and incisely lobed or dentate; heads 

 panicled, very numerous, small, 3-5 mm. high; involucres cylindric; ray- 

 flowers whitish, very small. 



Native but weedy in habit and abundant in cultivated land. 



Erigeron acris debilis Gray. Biennial, erect, glabrous or sparsely pubes- 

 cent, 10-20 cm. high; basal leaves spatulate-lanceolate; cauline lanceolate, 

 sessile, all entire, acute or obtuse, 5-10 cm. long; heads few, paniculate or 

 corymbose, 6-8 mm. broad; involucre puberulent and somewhat hirsute; ray- 

 flowers very narrow, pinkish, equalling the disk, within them a series of tubular 

 filiform pistillate flowers; akenes smooth; pappus copious, brownish. 



In the mountains at about 2000 m. altitude. 



Erigeron ramosus septentrionalis Fernald & Wiegand. Annual or biennial, 

 erect, branched above, sparsely hirsute, leafy to the top; lower leaves spatulate- 

 lanceolate, acute, entire or dentate, the blades 5-8 cm. long; upper cauline 

 lanceolate, entire, sessile, smaller; heads loosely corymbed; involucre 3-4 mm. 

 high, glabrous or with a few bristly hairs; ray-flowers white, numerous, short, 

 4-6 mm. long; pappus of the disk-flowers double, the inner of few deciduous 

 bristles, the outer of short persistent scales; ray-flowers with few or no bristles 

 to the pappus. 



Prairies, not uncommon. 



Erigeron aureus Greene. (Aplopappus brandegei Gray.) Perennial from 

 a stout crown; herbage ashy-puberulent; stems 6-12 cm. high; leaves mostly 

 basal, obovate to spatulate, entire, petioled; cauline oblong to lanceolate, few, 

 small; heads solitary, 8-10 mm. broad; involucre loose, woolly; tegules lan- 

 ceolate; ray-flowers 15-20, bright yellow; akenes pubescent. 



High peaks of the Cascade Mountains at about 2700 m. altitude, British 

 Columbia and Washington; first found on Mount Stuart. 



Erigeron compositus trifidus (Hook.) Gray. Biennial, tufted from a 

 woody crown; basal leaves petioled, the blade 3-cleft, the lateral lobes often 

 again cleft; cauline sessile, often entire; flowering stems 5-10 cm. high; heads 

 solitary; ray-flowers 30-50, pink or white, 6-10 mm. long; akenes short-pubes- 

 cent; pappus simple. 



In rocky soil in the mountains at about 2500 m. altitude. 



Erigeron compositus discoideus Gray. Similar to E. compositus trifidus; 

 ray-flowers absent. 



Cascade Mountains, latitude 49°, Lyall. 



Erigeron uniflorus L. Perennial; stems erect, simple, 4-20 cm. high, 

 somewhat pubescent; basal leaves spatulate, obtuse, entire, 2-5 cm. long, the 

 blade as long as the petiole; cauline leaves lanceolate, acute, sessile; head 



