98 AMARANTHACEAE 



Family 37. AMARANTHACEAE. 



Amaranth Family. 



Herbs or shrubs, or some tropical species trees, with opposite or alternate usually 

 entire leaves and no stipules. Flowers solitary, racemose, spicate or capitate, perfect, 

 polygamous or dioecious, each (or rarely each cluster of 2-5) subtended by a bract 

 and two bractlets, these usually hyaline, never foliaceous. Calyx rarely wanting, the 

 segments 5 or rarely 1-4, free or united at base, equal or the inner often shorter, 

 usually scarious or chartaceous, rarely herbaceous. Corolla wanting. Stamens op- 

 posite the calyx-segments and of the same number, fewer or rarely more numerous ; 

 filaments free or united below into a tube ; anthers dorsi-fixed, 1-2-celled. Ovary 

 superior, 1-celled; stigmas 2 or 3 ; ovules solitary (numerous in some tropical spe- 

 cies), amphitropous. Fruit a utricle, circumscissile, irregularly dehiscent, or inde- 

 hiscent. Seeds erect or inverted, often shiny, naked or arillate ; endosperm copious. 



A family of about 55 genera and 500 species, most abundant in tropical regions. 



Leaves alternate; plants not white-tomentose, annuals; filaments distinct; anthers 2-celled. 1. Amaranthus. 



Leaves opposite: our species perennial and white-tomentose; filaments connate at base; anthers 1-celled. 



r 2. Tidestromia. 



1. AMARANTHUS L. Sp. PI. 989. 1753. 



Annual herbs, with alternate petioled, undulate or crisped leaves. Flowers glomerate, 

 the glomerules axillary, spicate or paniculate, polygamous, monoecious or dioecious. 

 Sepals 2-5, distinct. Stamens usually of the same number as the sepals; filaments dis- 

 tinct; anther 2-celled. Utricle dehiscent or indehiscent; seed solitary, erect, smooth and 

 lustrous, compressed. [Name Greek, meaning unfading flower.] 



About 50 species, native of tropical and warm temperate regions. Type species, Amaranthus caudatus L. 



Utricle circumscissile. 



Sepals of the pistillate flowers oblong to lanceolate, usually narrowed above. 

 Flowers, at least the upper, in simple or paniculate spikes. 



Spikes thick, simple or usually crowded in a stiff glomerate panicle. 1. A. retroflexus. 



Spikes slender-cylindric, flexuous, usually in ample panicles. 2. A. hybridus. 



Flowers in axillary glomerules. 



Plants erect, bushy-branched; utricle wrinkled. 3. A. graecizans. 



Plants prostrate. 



Sepals of the pistillate flowers 4 or 5, 2.5-3 mm. long. 4. A. blitoides. 



Sepals of the pistillate flowers 1-3, one narrowly lanceolate, the others reduced and scale-like, 

 or wanting. 5 - A - cahformcus. 



Sepals of the pistillate flowers spatulate. 



Flowers dioecious; sepals of the pistillate flowers not fimbriate. 6. A. Palmeri. 



Flowers monoecious; sepals of pistillate flowers fimbriate. 7. A. fimbriata. 



Utricle indehiscent, slightly fleshy, 3-5-nerved. 8 - A - deflexus. 



1. Amaranthus retroflexus L. Rough Pigweed, Green Amaranth. Fig. 1559. 



Amaranthus retroflexus L. Sp. PI. 991. 1753. 



Amaranthus Powellii S. Wats. Proc. Amer. Acad. 10: 347. 1875. 



Stems stout, erect, simple or usually branched, 3-15 dm. high, roughish-puberulent below and 

 more or less villous-pubescent above. Leaves long-petioled, ovate or rhombic-ovate, undulate, 

 somewhat pubescent at least on the veins beneath, dull green; spikes thick, usually 8-15 mm. 

 thick crowded into a stiffly erect glomerate panicle; bracts attenuate into a rigid spmose tip; 

 sepals distinctly shorter than the bracts, lanceolate-oblong, acute or obtuse and spinulose-tipped; 

 stamens 3 or 5 ; utricle rugulose above ; seed compressed, rounded or obovate, black and shining. 



Waste places, cultivated fields and gardens, Sonoran and Transition Zones; throughout the Pacific States 

 and across the continent. Native of tropical America. Also known as Red Root. June-Dec. 



2. Amaranthus hybridus L. Spleen Amaranth, Slender Pigweed. Fig. 1560. 



Amaranthus hybridus L. Sp. PI. 990. 1753. 

 Amaranthus hypochondriaceus L. Sp. PI. 991. 1753. 

 Amaranthus chlorostachys Willd. Amaranth. 34. 1790. 



Closely resembling the preceding species, the stems more slender, 5-15 dm. high, smooth or 

 pubescent. Leaves darker green; spikes slender, simple or more or less densely paniculate, 

 spreading or drooping ; bracts long-awned ; sepals 5, oblong, acute and cuspidate ; utricle nearly 

 smooth ; seeds rounded, black and shining. 



Waste places and cultivated ground, Sonoran and Transition Zones; geographical range about the same as 

 that of the prece S dl ng species, but less common in the Pacific States. The foliage and inflorescence sometimes 

 tinged with red. June-Dec. 



Amaranthus cruentus L. Syst. ed. 10. 1269. 1759. This Chinese ornamental plant is an occasional escape 

 in Washington {St. John). Differs from A. retroflexus mainly in purple instead of green inflorescence and in 

 smaller sepals (1.5 mm. long). 



