126 AMAEANTHACEAE. 



1. Centrostachys indica (L.) Standley, Journ. Wash. Acad. Sci. 5: 75. 1915. 



Achyranthes aspera indica L. Sp. PI. 204. 1753. 

 Achyranthes indica Mill. Gard. Diet. ed. 8, no. 2. 1768. 

 Achyranthes ohtusifolia Lam. Encycl. 1: 545. 1785. 

 Aohyrantlies aspera oMusifolia Griseb. El. Br. W. I. 62. 1859. 



Herbaceous, erect or ascending, simple or branched, 6-12 dm. high, rather 

 densely pubescent above. Leaves suborbicular or obovate-orbieular, pubescent, 

 2-5 cm. long, abruptly short-tipped at the apex, narrowed or cuneate at the 

 base, pinnateiy veined, the slender petioles 1-3 cm. long; spikes very slender, 

 2-6 dm. long, densely flowered above, the lower flowers scattered; flowers 

 about 4 mm. long; bracts subulate, horny, glabrous, a little shorter than the 

 calyx, deflexed; sepals acuminate. 



A weed in waste places and cultivated soils, throaghcut the archipelago from 

 Abaco south to Acklin's Island : — a weed in tropical and subtropical regions. 

 Blunt-leaved Cbnteostachys. 



4. ACHYRANTHES L. Sp. PI. 204. 1753. 



Decumbent or prostrate herbs. Leaves opposite, entire or nearly so. 

 Flowers perfect, in sessile or peduneled, head-like, usually white or silvery 

 spikes. Sepals 5, unequal. Stamens 5, the filaments partially united into a 

 cup-like tube; staminodia surpassing the filaments and 2-celled anthers, or 

 shorter. Ovary 1-celled; stigma capitate. Ovule solitary. Utricle flattened, 

 indehiscent. Seeds lenticular, smooth. [Greek, straw-flower.] Forty species 

 or more, mostly of tropical distribution. Type species: Achyranthes repens L. 



Plants succulent : leaves sessile. 1. A. marithna. 

 Plants not succulent. 



Sepals merely acute. 2. A. polygonoides. 



Sepals spinulose-tipped. 3. A. repens. 



1. Achyranthes maritima (St. Hil.) Standley, Journ. Wash. Acad. Sci. 5: 



74. 1915. 



Alternamthera maritima St. Hil. Voy. Bras. 2: 437. 1833. 



Plants glabrous, fleshy. Stems or the branches prostrate, 2-8 dm. long, 

 angled, branched; leaves leathery, cuneate to oblong or elliptic, 1.5-6 cm. long, 

 obtuse, commonly mueronate, entire, sessile or somewhat petioled; spikes dull 

 straw-colored, 6-12 mm. long, sessile, leaving a conspicuous sear when detached; 

 bracts ovate, keeled ; calyx J longer than the bracts ; sepals rigid, ovate, acute 

 and slightly awn-tipped, usually 5-nerved, glabrous ; staminodia longer than 

 the filaments, cleft or lacerate at the tip. 



Maritime sands at the wave line, Great Bahama, Frozen Cay, South Bimini, 

 Little Mangrove Cay, New Providence and Cat Island : — Bermuda : Florida : Cuba ; 

 Guiana to Brazil : west coast of Africa. Referred to by DoUey and by Herrick as 

 Oomphrena sp. Beach Achteanthes. 



2. Achyranthes polygonoides (L.) Lam. Encycl. 1: 547. 1785. 



Gomphrena polygonoides L. Sp. PI. 225. 1753. 



Alternanthera paronychioides St. Hil. Voy. Bras. 2: 439. 1833. 



Glabrous or sparingly pilose, branched, the branches procumbent or creep- 

 ing, 1-4 dm. long. Leaves spatulate to elliptic, 2 cm. long or less, obscurely 

 veined, acute or obtuse at the apex, narrowed at the base, the petioles 5-10 mm. 

 long; flowers in dense sessile globose axillary heads 8-12 mm. in diameter; 

 sepals bright white, shining, lanceolate, acute, slightly unequal, about 3 mm. 



