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



mixed with water. The leaves and young shoots were used for greens, 

 the Hopi Indians usually boiling them with meat. This tribe is 

 reported to have used the ashes of A. canescens as a substitute for 

 baking powder. The pollen of many species is a cause of hay fever. 



Key to the species 



1. Fruiting bracts fleshy-thickened and bright red at maturity, deltoid-cuneate, 

 coarsely few-toothed; plant perennial; stems prostrate or nearly so, some- 

 times woody below, much-branched; leaf blades whitish scurfy beneath, 

 glabrate above, oblong or obovate-oblong, shallowly dentate or entire. 



3. A. SEMIBACCATA. 



1. Fruiting bracts not becoming fleshy-thickened and bright red (2). 



2. Stems herbaceous; plants mostly annual, commonly monoecious, the stami- 

 nate and pistillate flowers in the same or in separate clusters (3). 

 3. Leaf blades triangular-hastate, commonly becoming glabrate and green 

 on both faces, the lowest leaves often opposite; fruiting bracts acute 

 or acutish, rounded deltoid, often hastate, united only at base. 



1. A. PATULA. 



3. Leaf blades not distinctly hastate, sometimes subhastate, usually remaining 



scurfy and whitish, grayish, or yellowish, at least on the lower surface 



4. Fruiting bracts (often those in the same axil) commonly distinctly 

 dimorphic, some of them wedge-shaped, about 3 mm. long, broadly 

 truncate and emarginate or denticulate at apex and with smooth 

 faces, others rounded- triangular or suborbicular, larger, with dentate 

 margins and prominently crested faces; leaf blades more or less 

 cordate at base, broadly triangular to suborbicular, the margins 



entire 4. A. saccaria. 



4. Fruiting bracts not noticeably dimorphic; leaf blades not cordate at 

 base (5). 

 5. Bracts of the fruits orbicular, their margins herbaceous and evenly 



dentate all around 7. A. elegans. 



5. Bracts of the fruits not orbicular (sometimes semiorbicular in A. 



argentea), their margins not herbaceous and evenly dentate all 



around (6). 



6. Leaf blades strongly 3-nerved from the base with long, ascending, 



lateral nerves, entire, whitish farinose beneath; fruiting bracts 



conspicuously differentiated into a 2- to several-crested basal 



portion and a smooth, truncate and apiculate, or acute, apical 



portion; plant sometimes with arachnoid as well as scurfy 



pubescence 6. A. powellii. 



6. Leaf blades not strongly 3-nerved from the base, or if so, the lateral 



nerves short or spreading or the margins of the blades dentate; 



fruiting bracts not conspicuously differentiated basally and 



apically (7). 



7. Staminate flowers in conspicuous naked or nearly naked terminal 



panicles; leaf blades seldom less than 3 times as long as wide; 



fruiting bracts 2 to 3 mm. long (8) . 



8. Leaf blades obtuse to acute at apex, commonly widest above 



the middle, densely white-farinose beneath when mature; 



fruiting bracts strongly ribbed but usually not tuberculate 



on the faces, broadly deltoid or somewhat wedge-shaped, 



coarsely dentate 8. A. wrightii. 



8. Leaf blades sharply acute or acuminate at apex, widest at or 



below the middle, sparsely farinose or glabrate beneath 

 when mature; fruiting bracts usually tuberculate on the 



faces 9. A. serenana. 



7. Staminate flowers not in conspicuous naked panicles; leaf blades 



less than 3 times as long as wide; fruiting bracts more than 



3 mm. long at maturity (9). 



9. Leaf blades oblong-lanceolate to ovate, conspicuously and some- 



times acutely dentate, sometimes green and glabrate on both 

 faces when mature; fruiting bracts rhombic or deltoid, 

 cuneate at base, acutish to short-acuminate at apex, dentate, 

 strongly 3-nerved, usually short-crested on the faces. 



2. A. rosea. 



