564 HYPERICACEAE 



lanceolate, acuminate; petals oval or obovate, 2-3 mm. long; stamens 5-10; 

 capsule narrowly conic. H. canadense majus A. Gray. Wet places: Me. 

 N.J. Colo. Wash. B.C. Plain Submont. Jl-Au. 



FAMILY 83. ELATINACEAE. WATER-WORT FAMILY. 



Herbs or shrubby plants, ours low water herbs, with opposite or whorled 

 leaves, with stipules. Flowers inconspicuous, perfect, regular, solitary or 

 clustered in the axils of the leaves. Sepals 2-5, imbricate. Petals as many, 

 hypogynous. Stamens 2-5, or sometimes 10. Gynoecium of 2-5 united 

 carpels. Ovary 2-5-celled, with central placentae; stigmas 2-5, distinct. 

 Fruit a septicidal capsule. 



1. ELATINE L. WATER-WORT, MUD-PURSLANE. 



Low water plants. Leaves opposite or whorled, entire. Flowers usually 

 solitary, axillary. Sepals 2-4, membranous, obtuse, nerveless. Petals and 

 stamens as many as the sepals or the latter twice as many. Ovary and fruit 

 2-4-celled. Styles 2-4. Capsule membranous, 2-4-valved. 



Flowers sessile; stamens 2-3, as many as the petals. 



Leaves oblanceolate ; flowers usually 3-merous. 1. E. triandra. 



Leaves obovate. 



Flowers 3-merous; plant red; leaves 2 mm. long. 2. E. rubella. 



Flowers 2-merous; plant green; leaves 4-6 mm. long. 3. E. americana. 



Flowers pedicelled; stamens 6-8, twice as many as the sepals and petals. 



4. E. WiUiamsii. 



1. E. triandra Schkur. Immersed water plant, flaccid; stems 5-10 cm. 

 long; leaves opposite, oblong or oblanceolate; flowers sessile; sepals usually 2; 

 seeds slightly curved, little sculptured. Shallow water: 111. Colo. Wash.; 

 Eu. Plain Submont. 



2. E. rubella Rydb. Low and depressed annual, whole plant reddish; 

 stems scarcely more than 5 mm. long; leaves opposite, broadly obovate-spatu- 

 late, fleshy; flowers sessile; pod depressed-globose, 1.5 mm. in diameter; seeds 

 curved, sculptured as in the next. Wet volcanic sand: Yellowstone National 

 Park. Mont. 



3. E. americana (Pursh) Arn. Diffuse rooting annual; stems 1-4 cm. long; 

 leaves obovate, very obtuse, 2-6 mm. long; petals in the terrestrial form rose- 

 colored; pod globose, 1 mm. in diameter; seeds slightly curved, sculptured with 

 9-10 longitudinal and 20-30 cross-bars. Mud and shallow water: Que. Va. 

 Tex. Calif. B.C. Plain Submont. Jl-S. 



4. E. WiUiamsii Rydb. Slender diffuse annual; stems 3-5 cm. long; leaves 

 broadly spatulate, distinctly petioled, 5-8 mm. long, thin, indistinctly 3-nerved; 

 flowers on pedicels 1-2 mm. long; capsule 1.5 mm. in diameter; seeds curved 

 into a hook, less than 0.5 mm. long, with numerous cross-lines. Shallow water: 

 Mont. Au-S. 



FAMILY 84. FRANKENIACEAE. FRANKENIA FAMILY. 



Low herbs or undershrubs, with opposite or whorled, entire, thick leaves, 

 with a stipular membrane connecting their bases. Flowers small, perfect, 

 regular. Sepals 4 or 5, united into a tube. Petals as many, clawed. Gynoe- 

 cium of 3 or 4 united carpels; ovary 1-celled, with as many parietal placentae. 

 Fruit a capsule, septicidal, enclosed in the calyx. 



1. FRANKENIA L. 



Characters of the family. 



1. F. Jamesii Torr. Erect shrub, 3-6 dm. high, thickly branched; branches 

 scabrous-puberulent; leaves nearly glabrous, linear, 5-10 mm. long, with re volute 

 margins, fascicled; petals white; blades 4 mm. long, cuneate, erose-truncate ; 



