80 CHENOPODIACEAE 



Plants not glandular nor aromatic. 



Pericarp easily separateil fiom the seed. 



Calyx lobes barely keeled. 2. C. Bosiinnum. 



Calyx lobes strongly keeled. 



Leaves linear to oblong. 3. C. lepfophylhtm. 



Leaves triangular-hastate. 4. C. Fremonlii iiicanum. 



Pericarp separated from seed Avith difficulty. 

 Leaves coarsely 2-8-toothed. 

 Leaves sinuate to i«cised. 

 Sepals strongly keeled. 

 Sepals not keeled in fruit. 



Leaves white-glaucous beneath. 

 Leaves green on both sides. 

 Seeds with rounded margins. 

 Seeds with acute margins. 

 Plants glandular or aromatic. 



Leaves sinuate-pinnatitid. 9. C. Botrys. 



Leaves repand-dentate to incised. 



Flowers in leafy spikes. 10. C. ambrosinides. 



Flowers in leafless spikes. IL C. anlhelminticum. 



1. C. album I>. Pigweed. Erect annual, 6' -10° high, mealy : 

 leaves rhombic-ovate to linear lanceolate, at least the lower usually angu- 

 late-toothed, acuminate to obtuse : spikes in terminal clusters. — ^Abun- 

 dant in waste places. May-November. A form with linear entire leaves 

 occurring in the southern part and apparently native may be distinct. 



Var. viride ( L. ) Moq. Plant not mealy : leaves obtuse or acute. — 

 Infrequent in waste places. 



Var. Berlandieri (Moq.) Mackenzie & Bush, n. comb Plant not 

 mealy : leaves cuspidate or bristle-tipped. — Abundant in waste places. 

 (C. lierlnndkri Mo(i. ) 



2. C. BoBcianum Moq. Wood Pigwked. 1°-4° high, not mealy : 

 leaves oblong-lanceolate, slender-petioled, nearly entire : flowers in 

 slender, terminal spikes on widely diverging branches. — Common in 

 woods and thickets July-October. 



3. C. leptophyllum (Moq.) Nutt. N.\rhow-leaved Pigwkkd. 

 Annual, G'-'MV high, more or less mealy : leaves linear to oblong-linear, 

 entire : branches erect : flowers densely clustered. — Infrequent along rail- 

 roads and in sandy soil throughout. May-October. 



Var. oblongifolium S. Wats. Leaves oblong. — With the type but 

 much more common. 



4. C. Fremontil incanum S. Wats. PuAiuiE I'KiWKED. Annual, 

 about Q' high, erect, mealy : leaves broadly triangular-hastate, sinuate- 

 dentate, densely mealy on both sides : spikes slender, axillary and ter- 

 minal. — Has been found as a waif at Courtney: also at Armstrong, 

 Kanstis. July-September. 



5. C. urbicum L. City Pigwekd. Dull green annual, 1^3' high, 

 not mealy, erect: leaves triangular-ovate, irregularly dentate: spikes 

 terminal and axillary, the upper longer than the leaves. — Waste places in 

 Kansas City and Sheffield. Not common. .June-September. 



