POBTULACACEAE. 137 



within, the back prolonged into an appendage; stamens numerous; capsule 

 conic, 8-10 mm. long. 



Sea beaches and saline borders, throughout the archipelago to Turks Island and 

 Cay Sal : — Bermuda ; North Carolina to Florida ; the West Indies ; Mexico to Co- 

 lombia and Venezuela ; Old World tropics. Plants from saline borders have smaller 

 leaves and seeds than those from sea beaches and coastal rocks. Sea Poeslaxe. 



Family 7. ALSINACEAE Wahl. 



Chickweed Family. 



Annual or perennial herbs with opposite entire leaves, estipulate or 

 stipulate, and mostly small perfect flowers, solitary or in cymes or umbels. 

 Calyx of 4 or 5 sepals, imbricated, at least in the bud, separate to the 

 base, or nearly so. Petals as many as the sepals, not clawed, rarely 

 wanting. Stamens twice as many as the sepals, or fewer, inserted at the 

 base of the sessile ovary, or on a small disk; filaments distinct, or cohering 

 below; anthers introrse, longitudinally dehiscent. Ovary usually 1-celled; 

 styles 2-5, distinct; ovules several or numerous, amphitropous or campylo- 

 tropous, borne on a central column. Fruit a capsule, dehiscent by valves 

 or by apical teeth. Embryo mostly curved and with incumbent cotyledons. 

 About 32 genera and 500 species, of wide distribution, most abundant in 

 temperate regions. 



1. DBYMAEIA "Willd; R. & S. Syst. 5: 406. 1819. 



Low branching herbs, with flat small leaves, small, often fugacious stip- 

 ules, and small mostly white flowers in cymes or solitary. Sepals 5, distinct. 

 Petals 5, cleft. ' Stamens 5 or fewer. Ovary 1-celled, many-ovuled; style 

 mostly 3-cleft. Fruit a 5-valved capsule. Seeds globose-reniform, the embryo 

 peripheral. [Greek, pertaining to the forest.] About 20 species, of tropical 

 and subtropical America, one also in the Old World tropics. Type species: 

 Iirymaria arenarioides H. & B. 



1. Dryraaria cordata (L.) Willd.; E. & S. Syst. 5: 406. 1819. 



Solosteum cordatum L. Sp. PI. 88. 1753. 



Annual, glabrous or puberulent above; stems very slender, diffuse, 1-4 

 dm. long. Leaves orbicular or broader than long, 6-20 mm. wide, membranous, 

 palmately veined, obtuse or cuspidulate at the apex, suboordate at the base, 

 short-petioled; peduncles filiform, usually much longer than the leaves, often 

 forked; cymes few-several-flowered; pedicels as long as the braotlets or 

 shorter; sepals 1.5-3 mm. long, oblong-lanceolate, acute; petals 2-cleft; stamens 

 2 or 3; capsule about as long as the sepals. 



Waste grounds, New Providence : — Florida ; West Indies and continental trop- 

 ical America. Dbymaeia. 



Family 8. PORTULAOACEAE Rchb. 



Purslane Family. 



Herbs, rarely somewhat woody, with regular perfect but unsymmet- 

 rical flowers. Sepals commonly 2 (rarely 5). Petals 4 to 6, rarely more, 



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