[*] 1. Ovary inferior; stamens borne upon the corolla, alternate with its lobes.
[+] Stamens distinct; leaves opposite or whorled; seed albuminous except in Valerianaceæ.
51. Caprifoliaceæ (p. 216). Corolla mostly 5-lobed, regular or irregular, the stamens as many (one fewer in Linnæa, doubled in Adoxa). Ovary 1–several-celled; fruit a berry, drupe, or pod, 1–several-seeded. Shrubs or herbs; leaves opposite, rarely stipular, not turning black in drying.
52. Rubiaceæ (p. 222). Flowers regular, 4–5-merous, the corolla mostly valvate. Ovary 2–4-celled. Herbs or shrubs; leaves simple, entire, opposite with stipules, or verticillate, usually turning black in drying.
53. Valerianaceæ (p. 228). Stamens (1–4) fewer than the lobes of the somewhat irregular corolla. Ovary with two abortive or empty cells and one containing a suspended ovule. Fruit dry and indehiscent. Herbs.
54. Dipsaceæ (p. 229). Flowers mostly 4-merous and with 4 (rarely 2) stamens, involucellate in involucrate heads; corolla-lobes imbricate. Ovary simple, 1-celled, with a suspended ovule. Herbs.
[+][+] Anthers connate into a tube.
55. Compositæ (p. 230). Stamens as many as the valvate corolla-lobes. Ovary with a solitary erect ovule, becoming an achene. Albumen none. Calyx-limb reduced to a pappus or none. Flowers in involucrate heads.
[*] 2. Ovary inferior (or superior in most Ericaceæ and in Diapensiaceæ); stamens free from the corolla or nearly so (adnate in some Diapensiaceæ), as many as the lobes and alternate with them, or twice as many; leaves alternate (opposite in some Ericaceæ); style 1.
[+] Juice milky; capsule 2–5-celled, many-seeded; herbs.
56. Lobeliaceæ (p. 305). Corolla irregular, 5-lobed. Stamens united, at least by the anthers. Capsule 2-celled or with two placentæ.
57. Campanulaceæ (p. 307). Corolla regular, 5-lobed, valvate. Stamens usually distinct. Capsule 2–several-celled.
[+][+] Juice not milky nor acrid; capsule 3–10-celled.
58. Ericaceæ (p. 309). Flowers mostly regular, 4–5-merous. Stamens distinct, more usually twice as many as the corolla-lobes or petals. Ovary inferior or superior. Herbs or shrubs.
59. Diapensiaceæ (p. 326). Flowers regular. Stamens 5, on the corolla, or monadelphous with 5 petaloid staminodia. Ovary superior, 3-celled.
[*] 3. Ovary superior; stamens as many as the corolla-lobes and opposite them.
60. Plumbaginaceæ (p. 327). Stamens 5, on the base of the petals. Styles 5. Fruit an achene or 1-seeded utricle. Herbs; leaves radical.
61. Primulaceæ (p. 328). Stamens 4–8, perigynous. Style 1. Fruit a capsule with several seeds on a central placenta. Herbs; leaves radical or opposite or alternate.
62. Sapotaceæ (p. 332). Flowers small, 4–5-merous. Style 1. Ovary few–several-celled; fruit fleshy, bearing a single bony-coated seed. Shrubs or trees, with milky juice and alternate entire leaves.
[*] 4. Ovary superior or more or less adnate to the calyx, few–several-celled, the cells 1-ovuled; stamens twice as many as the corolla-lobes or more; trees or shrubs, with alternate leaves.
63. Ebenaceæ (p. 333). Flowers diœcious or polygamous. Stamens on the corolla. Ovary superior. Styles distinct. Fruit fleshy, few-seeded.
64. Styracaceæ (p. 333). Flowers perfect. Stamens subhypogynous. Ovary more or less inferior. Style 1. Fruit dry or nearly so, 1–4-seeded.
[*] 5. Ovary superior, of two carpels (sometimes by division apparently 4-carpellary, sometimes of 3–5 in Polemoniaceæ, Convolvulaceæ, and Solanaceæ); stamens on the corolla (except in apetalous Oleaceæ), alternate with its lobes, as many or fewer.
[+] Corolla not scarious and nerveless.
[++] Corolla none, or regular and 4-cleft or -parted, the stamens fewer than its lobes; style 1; seeds 1–3.
65. Oleaceæ (p. 335). Trees or shrubs, with opposite and pinnate or simple leaves. Flowers perfect or polygamo-diœcious. Stamens mostly 2, alternate with the usually 2-ovuled carpels.
[++][++] Corolla regular, its lobes 4–5 or rarely more; stamens as many.
[=] Ovaries 2, becoming follicles; stigmas and sometimes the styles united; herbs with milky juice, perfect 5-merous flowers, and simple entire leaves.
66. Apocynaceæ (p. 337). Stamens distinct or the anthers merely connivent, with ordinary pollen. Style 1.
67. Asclepiadaceæ (p. 338). Stamens monadelphous, the anthers permanently attached to a large stigmatic body; pollen mostly in waxy masses. Styles distinct below the stigma.
[=][=] Ovary compound (ovaries two in Dichondra), with 2 or 3 (rarely 4 or 5) cells or placentæ; stamens distinct; mostly herbs.
a. Leaves opposite; corolla-lobes 4 or 5 or more.
68. Loganiaceæ (p. 345). Leaves entire, with stipules or a stipular line joining their bases. Capsule 2-celled, few–many-seeded. Herbs or woody twiners (our species).
69. Gentianaceæ (p. 346). Glabrous herbs; leaves entire, sessile and simple (except in Menyanthes). Capsule 1-celled with 2 parietal placentæ or the whole inner surface ovuliferous, many-seeded.
b. Leaves alternate (sometimes opposite in Polemoniaceæ and Hydrophyllaceæ); corolla-lobes always 5 in our species.
70. Polemoniaceæ (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. Hydrophyllaceæ (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 placentæ, or sometimes 2-celled. Seeds 2 or more on each placenta.
72. Borraginaceæ (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. Convolvulaceæ (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. Solanaceæ (p. 373). Style 1. Ovary 2-celled (rarely 3–5-celled), with numerous ovules on axillary placentæ, becoming a pod or berry. Cotyledons narrow.
[++][++][++] Corolla more or less bilabiately 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. Scrophulariaceæ (p. 377). Capsule 2-celled, with central placentæ. Seeds small, usually numerous. Herbs; leaves alternate or opposite.
76. Orobanchaceæ (p. 393). Root-parasites with no green foliage. Capsule 1-celled, with 2 simple or double parietal placentæ. Seeds many.
77. Lentibulariaceæ (p. 395). Aquatic or marsh