CHEXOPODIACEAE. 



115 



toothed or lobed, mostly petioled (in Salicornia reduced to mere ridges). 

 Flowers small, green or greenish, regular or slightly irregular, variously 

 clustered, occasionally solitary in the axils. Petals none. Calyx persistent, 

 2-5-lobed, 2-5-parted or rarely reduced to a single sepal, wanting in the 

 pistillate flowers of some genera. Stamens as many as the lobes or divisions 

 of the calyx, or fewer, and opposite them; filaments slender; anthers 2- 

 celled, longitudinally dehiscent. Disk usually none. Ovary 1-celled; ovule 

 solitary, amphitropous ; styles 1-3 ; stigmas capitate, or 2-3-lobed or divided. 

 Fruit a utricle, with a thin or coriaceous pericarp. Seed vertical or hori- 

 zontal; endosperm mealy, fleshy or wanting. About 75 genera and 550 

 species, of wide geographic distribution. 



Leafy herbs ; endosperm of the seed copious. 



Flowers perfect ; calyx 2-5-lobed. 



Flowers imperfect ; pistillate calyx none ; fruit enclosed in 



large bractlets. 

 Leafless herbs with opposite branches ; no endosperm. 



1. CHENOPODIUM L. 



1. Chenopodium. 



2. Atriplex. 



3. Sallcornin. 



Annual or perennial herbs, with alternate petioled leaves. Flowers small, 

 green, perfect, sessile, braetless, clustered. Calyx 2-5-parted or 2-5-lobed, em- 

 bracing or enclosing the utricle, its segments or lobes often keeled or ridged. 

 Stamens 1-5 ; filaments filiform or slender. Styles 2 or 3 ; seed horizontal or 

 vertical, sometimes in both positons in different flowers of the same species; 

 endosperm mealy; embryo completely or incompletely annular. [Greek, goose- 

 foot, from the shape of the leaves.] About 60 species, mostly weeds, of wide 

 geographic distribution. Type species: Chenopodium rubrum L. 



Embryo of the seed a complete ring ; plants not strongly odorous. 



Flowers in dense compound spikes. 

 Flowers in loose axillary panicles. 

 Embryo an incomplete ring ; plants strongly odorous. 



1. Chenopodium album L. 



LAMB'S QUARTERS. WHITE GOOSE- 

 FOOT. PIG- WEED. (Fig. 133.) An- 

 nual; stem usually slender, erect, 

 commonly much branched, l-9 tall. 

 Leaves rhombic-ovate or the upper 

 lanceolate, narrowed at the base, 3- 

 nerved, dentate, sinuate or lobed, or 

 the upper entire, l'-4' long; spikes 

 terminal and axillary, simple or com- 

 pound, often panicled ; calyx about 

 2" broad in fruit, its segments usu- 

 ally completely enclosing the utricle; 

 seed horizontal, black, shining, firmly 

 attached to the pericarp. 



In waste places, and cultivated 

 soil ; a common weed, naturalized from 

 Europe. Widely naturalized in warm 

 and temperate regions. Flowers from 

 winter to autumn. 



1. C. album. 



2. C. murale. 



3. C. ambrosioides. 



