WOOTON AND STANDLEY—FLORA OF NEW MEXICO. 683 
Leaves short, narrowly oblong, obtuse; heads 
NUMETOUS........----------- eee ee eee 6. A. boltoniae. 
Plants nowhere glandular. 
Outer bracts foliaceous, equaling or surpassing the inner. 
Plants low, 10 to 20 cm. high; leaves broad.........-- 8. A. apricus. 
Plants tall, 40 to 60 cm.; leaves narrow.......-.-.---- 9. A. canbyi. 
Outer bracts not conspicuously foliaceous, shorter than 
the inner. 
Bracts pubescent on the back, usually ciliate. 
Bracts not bristle-pointed; rays purple.......-..-10. A. vallicola. 
Bracts bristle-pointed ; rays usually white. 
Pubescence of the stems spreading or re- 
flexed. 
Heads small, 5 mm. high or less, very 
numerous........--- cece eee ee eeee 11. A. hebecladus. 
Heads larger, 7 mm. long or more, few. .12. A. crassulus. 
Pubescence of the stems appressed. 
Heads small, about 5 mm, high, numer- 
ous; bracts much imbricated, often 
reflexed.......----------------+5- 13, A. multiflorus. 
Heads larger, 7 mm. high or more, few; 
bracts nearly equal, erect......... 14. A. commutatus. 
Bracts glabrous, sometimes ciliate. 
Leaves conspicuously ciliate.........-.--------- 15. A. blepharophyllus. 
Leaves not ciliate. 
Plants glabrous throughout. 
Rays 2 mm. wide and 8 mm. long, showy; 
cauline leaves clasping........--- 16. A. laevis. 
Rays 1 mm. wide or less, not more than 
3 mm. long; cauline leaves not 
clasping. 
Stems much branched; leaves thick 
and fleshy, short; heads long- 
pedunculate......----------- 7. A, neomexicanus. 
Stems branched only above; leaves 
thin, long; heads short-pedun- 
culate.......-..0.0----------- 17. A. exilis. 
Stems pubescent, at least with pubescent 
lines above. 
Pubescence covering the peduncles. ..-. 18. A. lonchophyllus. 
Pubescence in lines on the peduncles. 
Heads short-pedunculate or nearly 
sessile; leaves thick........... 19. A. salicifolius. 
Heads long-pedunculate; leaves thin. 
Heads large, 10 to 15 mm. wide, 
few; stems little branched ; 
leaves of the inflorescence 
little reduced........----- 20. A. wootonii. 
Heads smaller, usually less than 
10 mm. wide, very nu- 
merous; stems tall, much 
branched; leaves of the 
inflorescence much re- 
reduced.........--------- 21. A. hesperius. 
