OP ARTS AND SCIENCES. 105 



Erect ; fruiting bracts denticulate, not muricate ; styles 

 included ; leaves lanceolate, entire. California . . 20. A. Coulteri. 



Procumbent; fruiting bracts acuminate, unequally 

 toothed, the sides naked or subcrested; leaves obo- 

 vate, petioled, entire. California 21. .4. Barclayana. 



Suberect; fruiting bracts margined nearly to the base, 

 7-toothed, the middle tooth largest ; styles very 

 short ; leaves undulate, sinuate. Key West . . 22. A. cristata. 



§ 6. Fruiting bracts orbicular, H-2^'f broad, with a double herbaceous toothed 

 margin, the sides carinate or rarely appendaged ; leaves narrow, V long 

 or less. 



* Apex of the fruiting bracts not foliaceous. 



Fruiting bracts \\" wide, radiately toothed, not appen- 

 daged ; leaves oblanceolate to linear, subdentate at 

 the apex. New Mexico 23. A. elegans. 



Fruiting bracts 2-2i^" wide, gash-toothed, rarely some- 

 what appendaged ; leaves lanceolate, entire. Cali- 

 fornia 2i. A. coronata. 



* * Fruiting bracts tooth-crested, with an acuminate foliaceous apex ; leaves 

 lanceolate, subentire. 



Flowers androgynous, axillary ; fruiting bracts with a 

 broad terminal lobe, doubly or triply tooth-crested; 

 leaves shortly petioled. Arizona 25. .4. Powellii. 



Male flowers in a naked panicle ; fruiting bracts with a 

 narrow apex, shortly appendaged ; leaves sessile. 



California 26. A. hracteosa. 



§ 7. Fruiting bracts rhombic-orbicular, united, indurated, subcompressed, 2-4" 

 long, usually conspicuously appendaged and the foliaceous margin 

 toothed and undulate; leaves triangular and subhastate, the lower 

 opposite. 



Male spikes short and dense ; leaves petioled. Eocky 



Mountains 27. A. argentea. 



Male spikes elongated, slender; leaves sessile; dis- 

 tantly branched. New Mexico to California . . 28. A. expansa. 



Sect. III. Perennials, more or less shrubby, appressed-scurfy : radicle usually 

 superior : leaves alternate. 



§ 8. Fruiting bracts orbicular to ovate, toothed, usually more or less appendaged 

 and somewhat spongy. 



* Fruiting bracts slightly compressed ; leaves ■J-2' long. 



Erect, woody ; fruiting bracts united to above the 

 middle 2" long or less, usually appendaged. Rocky 

 Mountains 29. A. Nuttallii. 



Erect, woody; bracts lanceolate, the linear apex only 



free, in fruit 4-6" long and strongly crested. Arizona. 30. A. acanthocarpa. 



Decumbent, subwoody at base ; bracts axillary, ovate, 

 3" long in fruit, united, usually crested, often not 

 toothed ; leaves thick, broad, obtuse. California . . 31. A. leucophylla. 



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