346 CARDUACEAE. 



2. Tonestus pygmaeus (T. & G.) A. Nels. (Aplopappus pygmaeus A. 

 Gray; Macronema pygmaeum Greene) On mountains of Wyo. and Colo. 

 Alt. 10,000-13,000 ft. Clear Creek; Gray's Peak; Little Kate Mine, La Plata 

 Mountains ; Mt. Princeton ; Cameron Pass, Larimer Co. ; Pike's Peak ; Bald 

 Mountain; Silver Plume; Mt. Garfield; near Pagosa Peak; Beaver Creek; 

 Raton Range; Middle Park. 



19. SOLID AGO L. GOLDEN ROD. 



Leaves glabrous or slightly pubescent along the veins and on the margins. 



Leaves not triple-veined ; branches of the inflorescence not recurved-spread- 



ing ; heads not secund. 



Bracts of the inflorescence lanceolate or linear-lanceolate, acute or acuminate. 

 Leaves ciliate at the base. I. VIRGAUREAE. 



Leaves not ciliate at the base. IV. GLABERRIMAE. 



Bracts of the inflorescence oblong or linear-oblong, obtuse. 



Leaves, at least the basal ones, toothed ; stem-leaves few ; plants 1-4 dm. 



high. II. HUMILES. 



Leaves all entire ; stem very leafy, 4-8 dm. high. III. SPECIOSAE. 



Leaves triple-veined ; heads more or less secund on recurved-spreading branches. 

 Plants slender, not very leafy, 2-4 dm. high ; stem-leaves narrowly oblan- 

 ceolate or linear. IV. GLABERRIMAE. 



Plant tall, leafy, 4-10 dm. high; stem-leaves lanceolate. V. SEROTINAE. 

 Leaves densely canescent. 



Leaves lanceolate ; bracts narrowly linear-lanceolate. VI. SEROTIXAE. 



Leaves, at least the lower ones, oblanceolate or obovate. VII. INCAN T AE. 



I. VIRGAUREAE. 



Plant low and slender, 1-3 dm. high ; inflorescence corymbiform ; branches with 



a single or a few corymbose heads. 

 Heads 7-9 mm. high ; inner bracts linear-lanceolate, of about the same length 



as the flowers and pappus; plant 2-3 dm. high. i. S. scopulorum. 



Heads 5-7 mm. high ; bracts lanceolate ; the inner shorter than the flowers and 



the pappus ; plant usually less than 2 dm. high. 2. 6". ciliosa. 



Plants stout, 3-4 dm. high ; inflorescence paniculate ; branches racemiform : heads 



7-9 mm. high. 

 Basal leaves broadly oblanceolate, acute ; stem pubescent. 



3. S. rubra. 



Basal leaves narrowly oblanceolate, obtuse ; stem glabrous up to the inflorescence. 



4. S. laericanlis. 



II. HUMILES. 



Plant low, 1-1.5 dm. high; inflorescence with few heads, short, congested. 



5. .5". decumbcns. 

 Plant taller, 2-4 dm. high ; inflorescence with many heads, elongated. 



Leaves not ciliate ; bracts oblong ; inflorescence usually narrow. 



6. S. oreophila. 

 Leaves ciliate at the base ; bracts linear ; inflorescence open. 



7. -5". dilatata. 



III. SPECIOSAE. 



One species. 8- $" pallida. 



IV. GLABERRIMAE. 



Heads less than 5 mm. high ; stem slender. 



Inflorescence decidedly viscid ; leaves indistinctly triple-veined. 



9. 5". viscidula. 

 Inflorescence not viscid ; leaves distinctly triple-veined. 



