usually white-mealy throughout to glabrous, obtusely angled, striate; leaves oval- 

 rhombic, rarely ovate or lanceolate, 2.5-8 cm. long, usually conspicuously longer 

 than broad, obtuse or rounded and apiculate at the apex, often shallowly 3-lobed, 

 irregularly sinuate-dentate, rarely subentire, mostly thick, pale-green and glabrate 

 above, very finely and commonly densely farinose beneath, the reduced upper 

 blades ovate to lanceolate, usually entire, acute and mucronate, not hastate; 

 flowers in large glomerules, these in dense axillary. or terminal stout erect or 

 ascending paniculate spikes to 3 dm. long, the inflorescence usually narrow and 

 compact, rarely lax, grayish-green, sparsely leafy; perianth copiously and finely 

 farinose, deeply lobed, the lobes green, white-margined, acutely keeled, completely 

 enclosing the fruit; pericarp adherent to the seed; seed horizontal, black, shining, 

 1.1-1.5 mm. broad, nearly smooth to minutely pitted, the margin obtuse. C. viride 

 L. 



In mud at edge of lakes, salt flats and on floodlands and in waste places 

 near marshes, uncommon in Tex., Okla. (Alfalfa Co.) and Ariz. (Apache, 

 Coconino, Yavapai and Pinal cos.), Mar.-Sept.; Euras. weed, Nfld. to Fla., w. to 

 Yuk. and B.C., s. to Mex. and S.A.; N. Afr. 



This species is commonly grazed by ducks and geese and represents an impor- 

 tant item of green food. The leaves and young plants are also eaten by people 

 as cooked greens. 



Fam. 53. Amaranthaceae Juss. Amaranth Family 



Weedy herbs and subshrubs, annuals or perennials, with erect to prostrate or 

 scandent stems; leaves alternate or opposite, petioled or sessile, without stipules; 

 flowers perfect to imperfect or polygamous, solitary or glomerulate, racemose, 

 spicate or capitate, each flower or flower cluster subtended by imbricate bracts; 

 perianth of 2 to 5 distinct scarious or chartaceous tepals, rarely 1 or entirely 

 absent in some species of Acnidci; corolla absent; stamens 2 to 5, opposite the 

 tepals; ovary superior, 1 -celled; styles 1 or 2 and terminal or absent; fruit a 

 membranous utricle, circumscissile, irregularly dehiscent or indehiscent; seeds 

 erect or inverted, lenticular, oblong or reniform-orbicular, smooth or nearly so, 

 lustrous; embryo annular, the cotyledons incumbent, the radicle inferior or superior. 



About 850 species in 65 genera, cosmopolitan but mosdy tropical. 



Most of our amaranths are found in weedy areas, commonly called "waste- 

 lands," one reason being because they are often poorly drained or subject to 

 flooding. Because of this, it is very possible that we should have included more 

 of these species. However, since we have based our treatment on factual evidence 

 instead of on speculation it must stand as is. 



1. Leaves alternate; anthers 4-celled; filaments distinct or united at the base (2) 



1. Leaves opposite; anthers 2-celled; stamens 2 to 5; flowers 5-merous (3) 



2(1). Perianth present in all flowers; stamens 5, rarely 1 to 3; bracts not much- 

 enlarged and not cordate in fruit 1. Amaranthus 



2. Perianth lacking or only occasionally present in pistillate flowers; stamens 5.... 



2. Acnida 



3(1). Stem erect; inflorescence paniculate; most of the flowers unisexual 



3. Iresine 



3. Stem prostrate or decumbent; inflorescence solitary heads or short spikes; 



few (if any) flowers unisexual (4) 



4(3). Style 1 or none; stigma 1 and capitate 4. Alternanthera 



4. Styles 1 or 2; stigmas typically 2 5. Philoxerus 



857 



