390 AMAKANTHACEAE 



present alternating with the fertile, lobed or toothed. Anthers introrse, 2-celled 

 or sometimes 1-celled. Gynoecium of a single pistil. Ovary solitary, 1-celled, 

 variable in shape, superior. Style terminal, sometimes almost wanting. Ovules 

 solitary or numerous, attached to the base of the cavity, amphitropous. Fruit 

 a membranous utricle or pyxidium, rarely a berry, 1 -many-seeded. Seed 

 lenticular or reniform, with a crustaceous testa. Embryo annular, often nearly 

 surrounding the endosperm. 



Anthers 2-celled. 

 Leaves alternate. 



Filaments united at the base : ovules 2-8 in a cavity. 1. CELOSIA. 



Filaments distinct : ovule solitary in each cavity. 



Perianth present in all flowers. 2. AMARANTHUS. 



Perianth wanting in pistillate flowers. 



Bracts of pistillate flowers narrow, soft and green throughout. 3. ACNIDA. 



Bracts of pistillate flowers cordate, scarious-margined and spine-tipped. 4. ACANTHOCHITON. 

 Leaves opposite. 5. ACHYRANTHES. 



Anthers 1-celled. 



Stamens perigynous. 6. BRAYULINEA. 



Stamens hypogynous. 



Stigmas capitate, notched or brush-like. 



Filaments united into a short cup at the base. 



Staminodia wanting. 7. GOSSYPIANTHUS. 



Staminodia present sometimes mere undulations. 



Foliage glabrous or pubescent with simple hairs : Staminodia longer 



than the filaments or shorter. 8. ALTERNANTHERA. 



Foliage pubescent with stellate hairs : Staminodia mere undulations. 9. CLADOTHRIX. 

 Filaments united into a long tube : calyx crested and often tubercled or 



spiny at maturity. 10. FROELICHIA. 



Stigmas 2-3, subulate or filiform. 



Flowers in head-like spikes, perfect. 



Pubescent plants: Staminodia present. 11. GOMPHRENA. 



Glabrous plants : Staminodia wanting. 12. LITHOPHILA. 



Flowers in panicles, dioecious. 13. IRESINE. 



1. CBLOSIA L. 



Annual herbs or shrubs, with upright or climbing stems. Leaves alternate : blades 

 entire or rarely lobed. Flowers perfect, subtended by bracts, in dense terminal or axillary 

 spikes. Sepals 5, scarious, striate. Stamens 5 : filaments united into a short tube at their 

 bases : anthers 2-celled. Ovary 1-celled : styles or stigmas 2-3, the latter sometimes 

 sessile. Ovules 2-8 in each cavity. Utricle included or exserted, circumscissile. Seeds 

 often erect, shining. 



1. Celosia paniculata L. Perennial, glabrous. Stems fully 1 m. long, more or less 

 widely branched : leaf -blades ovate, deltoid-ovate or ovate-lanceolate, 1.5-7 cm. long, acute or 

 slightly acuminate, entire, abruptly narrowed or truncate at the base ; petioles less than \ 

 as long as the blades : spikes solitary or panicled, 1-3 cm. long : sepals oblong, acute, 

 firm, 3.5-4 mm. long, much surpassing the bracts : utricle included : seed lenticular, 

 about 1 mm. long. 



In sandy soil, Florida, Texas and Mexico. 



2. AMARANTHUS L. 



Annual weedy herbs, with upright or diffusely branched and spreading stems, occasion- 

 ally armed with spines. Leaves alternate : blades flat, pinnately nerved, entire or undu- 

 late, sometimes crisped. Flowers' monoecious, polygamous or dioecious, in dense spikes or 

 clusters, each subtended by mostly 3 more or less conspicuous green, red or purple bracts. 

 Sepals 2-5, distinct. Stamens 2-5, distinct : anthers 2-celled, the sacs opening lengthwise. 

 Ovary 1-celled : styles or stigmas 2-3. Ovule solitary. Utricle circumscissile, irregularly 

 opening or indehisceni, 2-3-beaked. Seeds often lenticular and shining. Embryo annu- 

 lar. The plants flower in summer and fall or from spring to fall in the southern part of 

 our range. AMARANTH. PIGWEED. 



A. Sepals abruptly contracted into narrow claws. 

 Plants monoecious. 



Utricle indehiscent. 1. A. Berlandieri. 



Utricle circumscissile. 2. A, polygonoides~ 



Plants dioecious. 



Bracts scarious, acuminate, shorter than the sepals : stigmas usually 3. 3. A. Oregfiii. 



Bracts rigid, awn-tipped, longer than the sepals : stigmas usually 2. 4. A. Palmeri. 



