AMAKANTHACEAE. 123 



Anthers 4-celled. 

 Leaves alternate. 



Fruit several-seeded. 1. Celosia. 



Fruit 1-seeded. 2. Amaranthus. 



Leaves opposite. 3. Centrostachys. 



Anthers 2-celled. 



Stigma capitate. 4. Achyrdnthes. 



Stigma-lobes subulate or filiform. 

 Flowers in dense heads. 



Stamens 2 ; perianth sessile. 5. Lithophila. 



Stamens 5 ; perianth stalked. 6. Philoxerus. 



Flowers in panicled spikes. 7. Iresine. 



1. CELOSIA L. Sp. PI. 205. 1753. 



Herbs or shrubs, with alternate leaves and small perfect bracted flowers, 

 in spikes or fascicles. Perianth 5-parted, the segments scarious, striate. 

 Stamens 5; filaments filiform or subulate, connate at the base; anthers 4- 

 celled. Ovary 2-many-ovuled; style present or wanting; stigmas 2 or 3. 

 Utricle circumscissile or irregularly rupturing. Seeds 2 to many, lenticular, 

 shining; embryo annular, endosperm starchy. [Greek, burned, from the dry 

 parched flowers of some species.] About 40 species, of tropical and subtropical 

 distribution. Type species: Celosia argentea L. 



1. Celosia nitida Vahl, Symb. 2: 44. 1791. 



Perennial; glabrous. Stem slender, erect or vine-like, 3-15 dm. long; 

 petioles slender, 5-20 mm. long; leaves ovate to rhombic-lanceolate, 2-7 cm. 

 long, obtuse, acute or acuminate at the apex, truncate or obtuse and often 

 oblique at the base; inflorescence of panicled spikes, 1-5 cm. long; bracts 

 nearly half as long as the sepals, ovate to lanceolate, keeled, acuminate; sepals 

 elliptic-lanceolate, about 5 mm. long, acuminate, dark brown, strongly parallel- 

 veined; style short; utricle globose-ovoid, shorter than the calyx; seeds black, 

 smooth. 



Moist soil and thickets, Acklin's Island, Anguilla Isles : Florida ; West Indies ; 

 Texas ; Mexico ; northern South America. SLENDER CELOSIA. 



2. AMARANTHUS L. Sp. PI. 989. 1753. 



Annual branched erect or diffusely spreading glabrous or pubescent herbs, 

 with petioled pinnately veined leaves and small monoecious polygamous or 

 dioecious, green or purplish, mostly 3-bracteolate flowers in dense terminal spikes 

 or axillary clusters, Calyx of 1-5 distinct sepals. Stamens 1-5; anthers 

 longitudinally dehiscent. Styles or stigmas 2 or 3. Fruit an ovoid or oblong 

 utricle, 1-seeded, 2-3-beaked by the styles. Embryo annular. [Greek, unfad- 

 ing flower, from the dry, unwithering bracts.] About 60 species of wide 

 geographic distribution. Type species: Amaranthus caudatus L. 



Flowers all axillary ; sepals of pistillate flowers spatulate. 



Peduncles short and thick ; utricle indehiscent. 1. A. crassipes. 



Peduncles none ; utricle circumscissile. 2. A. polygonoides. 



Staminate flowers mostly in terminal spikes ; sepals of pis- 

 tillate flowers oblong or obovate. 

 Utricle indehiscent. 



Utricle smooth. 3. A. viridis. 



Utricle wrinkled. 4. A. gracilis. 



Utricle circumscissile or bursting irregularly. 



Leaf axils with a pair of spines. 5. A. spinosus. 



Plants not spiny. 



Plants glabrous or nearly so. G. A. dubius. 



Plants pubescent or villous. 7. A. hybridus. 



