69. Gentianaceae (p. 346). Glabrous herbs; leaves entire, sessile and simple (except in Menyanthes). Capsule 1-celled with 2 parietal placentae or the whole inner surface ovuliferous, many-seeded.

[b.] Leaves alternate (sometimes opposite in Polemoniaceae and Hydrophyllaceae); corolla-lobes always 5 in our species.

70. Polemoniaceae (p. 354). Capsule usually 3-celled, loculicidal; seeds 1--many in each cell on the stout placental axis. Style 3-cleft or -lobed. Leaves opposite or alternate, simple or compound.

71. Hydrophyllaceae (p. 357). Leaves often lobed or divided, and the inflorescence frequently scorpioid. Style 2-parted or 2-lobed. Capsule 1-celled, 2-valved with two parietal or introflexed placentae, or sometimes 2-celled. Seeds 2 or more on each placenta.

72. Borraginaceae (p. 360). Leaves mostly entire and plants often rough-hispid; inflorescence commonly scorpioid. Style 1. Ovary 4-ovulate, usually 4-lobed and maturing as 4 separate or separable nutlets, or not lobed, 2--4-celled and separating when ripe into 2 or 4 nutlets.

73. Convolvulaceae (p. 367). Usually twining or trailing; flowers on axillary peduncles or cymose-glomerate. Corolla 5-lobed or 5-plaited, twisted in the bud. Styles 1 or 2. Ovary 2- (sometimes 3- or spuriously 4-) celled, becoming a globular 4--6-seeded capsule (or ovaries two and distinct in Dichondra). Cotyledons broad-foliaceous.

74. Solanaceae (p. 373). Style 1. Ovary 2-celled (rarely 3--5-celled), with numerous ovules on axillary placentae, becoming a pod or berry.

Cotyledons narrow.

[++][++][++] Corolla more or less bil.a.b.i.ately irregular (sometimes nearly regular), 5-lobed. Fertile stamens 4 and didynamous, or 2. Style 1. Ovary always of two carpels.

[a.] Ovules several or many.

75. Scrophulariaceae (p. 377). Capsule 2-celled, with central placentae.

Seeds small, usually numerous. Herbs; leaves alternate or opposite.

76. Orobanchaceae (p. 393). Root-parasites with no green foliage. Capsule 1-celled, with 2 simple or double parietal placentae. Seeds many.

77. Lentibulariaceae (p. 395). Aquatic or marsh herbs, with scapes or scape-like peduncles, sometimes nearly leafless. Corolla personate and spurred. Capsule globular, 1-celled; placentae central, free, many-seeded.

78. Bignoniaceae (p. 398). Large-flowered trees or often climbing shrubs, with usually opposite simple or compound leaves. Capsule 2-celled by a part.i.tion between the 2 parietal placentae. Seeds numerous, large, mostly winged.

79. Pedaliaceae (p. 399). Herbs, with opposite simple leaves. Ovary 1-celled with two bilamellar parietal placentae, or 2--4-celled by their union, becoming drupaceous or capsular. Seeds few or many, wingless.

80. Acanthaceae (p. 399). Herbs, with opposite simple leaves. Capsule 2-celled, loculicidal, with each axile placenta bearing 2--10 flattish seeds.

[b.] Cells of the ovary 1--2-ovuled; herbs or low shrubs, with opposite leaves.

81. Verbenaceae (p. 401). Ovary 2--4-celled, not lobed, the dry or drupaceous fruit separating into 2 or 4 1-seeded nutlets (fruit 1-celled and 1-seeded in Phryma). Style terminal.

82. l.a.b.i.atae (p. 403). Ovary deeply 4-lobed around the style, the lobes becoming dry seed-like nutlets. Stems square; aromatic.

[+][+] Corolla scarious and nerveless; flowers regular, 4-merous; style 1.

83. Plantaginaceae (p. 422). Scapose herbs, with perfect or polygamo-dicious or moncious flowers in 1--many-flowered spikes.

Fruit a circ.u.mscissile 2-celled capsule, with one or more peltate seeds in each cell, or an achene.

DIVISION III. APETALOUS EXOGENS. The corolla wanting (except in some Euphorbiaceae), and sometimes also the calyx.

[*] 1. Ovary superior (though sometimes enclosed within the calyx), 1-celled with a solitary basal ovule (several-celled in Phytolaccaceae); embryo coiled or curved (nearly straight in Polygonaceae) in or about mealy alb.u.men (alb.u.men none in some Chenopodiaceae); herbs.

[+] Fruit the hardened or membranous closed base of the corolla-like perianth enclosing a utricle.

84. Nyctaginaceae (p. 425). Perianth tubular or funnelform. Stamens hypogynous. Fruit ribbed or winged. Leaves opposite; stipules none.

[+][+] Fruit a utricle; perianth mostly persistent, small, 4--5-lobed or -parted, or none.

85. Illecebraceae (p. 426). Perianth herbaceous. Stamens perigynous.

Leaves opposite; stipules scarious (none in Scleranthus).

86. Amarantaceae (p. 427). Flowers sessile, bracteate, the bracts (usually 3) more or less dry and scarious, as well as the 3--5 distinct sepals. Stamens 1--5, hypogynous. Utricle indehiscent or circ.u.mscissile.

Embryo annular. Leaves mostly alternate, entire; stipules none.

87. Chenopodiaceae (p. 430). Flowers sessile, not scarious-bracteate.

Sepals greenish or succulent, 5 or fewer, or none. Stamens 5 or fewer, perigynous or hypogynous. Embryo annular or spiral or conduplicate.

Leaves alternate; stipules none.

[+][+][+] Ovary of several 1-ovuled carpels, in fruit a berry (in our genera).

88. Phytolaccaceae (p. 435). Sepals 4--5, petaloid or herbaceous. Stamens 5--30, hypogynous. Carpels 5--12. Embryo annular. Leaves alternate, entire; stipules none.

[+][+][+][+] Fruit a triangular or lenticular achene.

89. Polygonaceae (p. 436). Flowers on jointed pedicels. Calyx 3--6-lobed or -parted, more or less corolla-like. Stamens 4--12, on the calyx.

Embryo nearly straight. Leaves alternate, with sheathing stipules or none.

[*] 2. Ovary compound, the cells many-ovuled (or 1-ovuled in Piperaceae); embryo minute in copious alb.u.men; flowers perfect.

90. Podostemaceae (p. 444). Aquatic, with the aspect of sea-weeds or mosses, with minute naked flowers from a spathe-like involucre. Ovary superior; pod 2--3-celled.

91. Aristolochiaceae (p. 444). Terrestrial herbs or climbing shrubs.

Calyx valvate, adnate at least at base to the 6-celled many-seeded ovary. Stamens 6--12, more or less united with the style. Leaves alternate, mostly cordate; stipules none.

92. Piperaceae (-- Saurureae), (p. 446). Marsh herb (our species). Perianth none. Carpels 3--4, distinct, with usually a single ascending seed.

Leaves alternate, entire.

[*] 3. Ovary superior, simple, 1-celled, 1-ovuled, forming a berry or drupe; trees or shrubs, with mostly entire leaves and no stipules.

93. Lauraceae (p. 446). Flowers perfect or dicious. Sepals 4 or 6, in 2 rows. Stamens 9--12; anthers opening by 2 or 4 uplifted valves. Seed suspended; alb.u.men none. Aromatic; leaves alternate.

94. Thymelaeaceae (p. 448). Flowers perfect. Calyx corolla-like, 4--5-cleft. Stamens twice as many. Seed suspended, with little or no alb.u.men. Acrid shrubs with very tough bark; leaves alternate.

95. Elaeagnaceae (p. 448). Flowers mostly dicious. Calyx-tube becoming berry-like and enclosing the achene. Seed erect, alb.u.minous. Leaves silvery-scurfy, opposite.

[*] 4. Ovary inferior, 1-celled, 1--3-ovuled (but 1-seeded); alb.u.men without testa, bearing the embryo in a cavity at the apex; calyx-lobes valvate.

96. Loranthaceae (p. 449). Parasitic on trees, with jointed stems and opposite leaves. Flowers dicious. Ovule solitary, erect. Fruit a berry.

97. Santalaceae (p. 450). Flowers perfect. Ovules 2--4, suspended from the apex of a central placenta. Fruit dry, indehiscent. Leaves alternate.

[*] 5. Flowers all unis.e.xual (polygamous in some Urticaceae and Empetraceae, apparently perfect in Euphorbia); cells 1--2-ovuled; embryo nearly as long as the alb.u.men or filling the seed; calyx often wanting, corolla-like only in some Euphorbiaceae and Empetraceae; stipules often present.