918 MISC. PUBLICATION 42 3, U. S. DEPT. OF AGRICULTURE 



19. Plants perennial; involucre not conspicuously many-ranked 



(20). 



20. Leaves not glaucous; lower leaves much larger than the 



upper ones and petioled; involucre pubescent dorsally, 



not glandular 3. A. adscendens. 



20. Leaves glaucous or glaucescent; stem uniformly leafy, the 



leaves lanceolate to linear-oblong, sessile; involucre and 

 at least the upper part of the stem stipitate-glandular. 



7. A. GLAUCODES. 



19. Plants annual, biennial, or rarely perennial; involucre con- 

 spicuously many-ranked, the phyllaries with a whitish 

 chartaceous base and an abrupt, often squarrose, herbace- 

 ous tip (21). 



21. Herbaceous tips of the phyllaries comparatively short, 



usualty appressed, rhombic or narrowly triangular, 

 much shorter than the chartaceous whitish base (22) . 

 22. Phyllaries canescent-puberulent, with few or no glandular 

 hairs, their green tips usually narrow-triangular. 



19. A. CANESCENS. 



22. Phyllaries conspicuously glandular, their green tips 



usually rhombic 24. A. cichoriaceus. 



21. Herbaceous tips of the phyllaries comparatively long, 

 subulate, spreading, often as long as or longer than the 

 chartaceous whitish base (23) . 



23. Phyllaries densely cinereous-puberulous, scarcely or not 



at all glandular 20. A. tephrodes. 



23. Phyllaries more or less densely glandular, sometimes also 

 pubescent with eglandular hairs (24) . 

 24. Stem densely glandular-hispid and -hispidulous, 

 essentially without eglandular hairs. 



21. A. BIGELOVII. 



24. Stem with abundant eglandular hairs, sometimes also 



glandular (25). 



25. Plants relatively low (40 cm. high or less) ; leaves 



(except the lowest) linear or essentially so, those 



of the stem 3 mm. wide or less. 



22. A. ADENOLEPIS. 



25. Plants tall (60 cm. high or more); leaves mostly 

 lanceolate or oblong-lanceolate. 



23. A. AQUIFOLIUS. 



1. Aster pauciflorus Nutt., Gen. PI. 2: 154. 1818. 



Aster hydrophilus Greene ex Woot. and Standi., Contrib. U. S. 

 Natl. Herbarium 16: 187. 1913. 



San Bernardino ranch and valley of the San Pedro River (Cochise 

 County), Santa Cruz River valley (Pima County), 2,300 to 4,000 feet, 

 alluvial soil, May to September. Saskatchewan to Texas, New 

 Mexico, southeastern Arizona, and Mexico. 



2. Aster commutatus (Torr. and Gray) A. Gray, Syn. Fl. I 2 : 185. 



1884. 



Aster multiflorus var. commutatus Torr. and Gray, Fl. North 

 Amer. 2: 125. 1841. 



Widely distributed in Arizona, 5,000 to 8,000 feet, mostly in the 

 pine belt, August to October. Minnesota to British Columbia, south 

 to Texas, New Mexico, and Arizona. 



The typical form, with stems appressed-pubescent and phyllaries 

 subequal, has been collected at Flagstaff and Mormon Lake, Coconino 

 County (Fulton 6371, Collom 806). The var. polycephalus (Rydb.) 

 Blake (A polycephalus Rydb.), with stems appressed-pubescent and 

 involucre distinctly graduated, ranges from the Hopi Indian Reserva- 

 tion and the Grand Canyon to the mountains of Cochise and Pima 



