250 COMPOSITE FAMILY 



13. ERIGERON. Fleabane. 

 Technically distinguished from Aster only by the triangular 

 obtuse style-appendages, but usually also differs as follows: 

 involucral bracts narrow, little imbricated, without green tips; 

 rays very narrow, more numerous, in several rows; pappus 

 more scanty and fragile. 



Leaves clustered at base; heads solitary on nearly 

 naked peduncles. 

 Stems 6 in. or less high (rarely 9 in.); leaves short- 

 hairy. 



Leaves parted 1. E. cotnpositus. 



Leaves entire. 



Leaves spatulate 2. E. ursinus. 



Leaves linear 3. E. nevadensis. 



Stems 9 to 24 in. high; leaves nearly glabrous 4. E. salsuginosus. 



Leaves numerous along the flowering stems. 



Rays blue or violet (rarely whitish in no. 10), showy. 

 Pappus a single series of bristles. 



Leaves smooth, long 4. E. salsuginosus. 



Leaves rough, short. 



Plant tall; leaves J^ to 1J4 in- long 5. E. brezveri. 



Plant low, weak; leaves shorter 6. E. elmeri. 



Pappus double, the outer series very short. 



Perennial 9. E. concinnus. 



Annual 10. E. divergens. 



Rays white or pink or entirely wanting. 

 Heads entirely rayless. 



Stems low, gray-hairy 7. E. miser. 



Stems tall, nearly glabrous 8. E. inornatus. 



Heads with many showy white rays. 



Heads 1 to 4, large 11. E. coulteri. 



Heads many, small 12. E. ramosus. 



Heads with many small rays. 



Low plant; heads l / 2 in. across 13. E. armeriaefolius. 



Tall plant; heads not l /\ in. across 14. E. canadensis. 



1. E. compositus Pursh. Leaves crowded on the short 

 thick perennial stalks, forming dense mats, the blade short, 

 mostly with 1 to 3 lobes at the enlarged summit. Heads Yi 

 to 1 in. across, solitary on the nearly naked erect peduncles 

 which spring from the leafy mat and are only y 2 to 6 in. high. 

 Rays 40 to 60, light-purple or violet (entirely wanting in the 

 otherwise identical var. discoidea Gray). 



This compact little perennial, immediately known by its 

 peculiar leaves cut only at summit, is at home among the 

 granite peaks of our highest mountains, often growing near 

 banks of perpetual snow. It is not found until one has 

 ascended nearly to timber-line, when its purplish flowers may 

 be looked for in the crevices of rocks and in decomposed 

 granite. Such situations are plentiful in our Alpine Zone, a 



