GROUP 2, UNUSUAL PLANTS

1a. Small brown leafless plants, growing as parasites on the tamarack or black spruce[LORANTHACEAE], p. 25.
1b. Aquatic plants, with all or most of the leaves submerged, or leafless [— 2.]
1c. Aquatic plants, with the leaves or the whole plant floating on or near the surface [— 20.]
1d. Terrestrial or marsh plants, without floating or submerged leaves [— 29.]
2a. Submerged aquatics, without leaves [— 3.]
2b. Submerged aquatics, with the leaves linear or dissected [— 4.]
3a. Flowers showy, yellow or purple[LENTIBULARIACEAE], p. 105.
3b. Flowers small and inconspicuous, sessile, purplish or greenish[3a, in HALORAGIDACEAE], p. 79.
4a. Leaves linear or lanceolate, not lobed or dissected [— 5.]
4b. Leaves more or less lobed or dissected [— 13.]
5a. Leaves all basal [— 6.]
5b. Stem-leaves present [— 7.]
6a. Flowers blue, 1 cm. long or more; leaves cylindrical, blunt, hollow, partitioned lengthwise[1a, in LOBELIACEAE], p. 113.
6b. Flowers yellow; leaves minute[LENTIBULARIACEAE], p. 105.
6c. Flowers white, in clusters; leaves linear-lanceolate, acute, not hollow[1b, in ALISMACEAE], p. 3.
6d. Flowers greenish, solitary at the end of elongated peduncles; leaves very long and ribbon-like, flat or trough-shape[1a, in HYDROCHARITACEAE], p. 3.
6e. Flowers minute, whitish or lead-color, in heads[ERIOCAULACEAE], p. 9.
7a. Leaves alternate [— 8.]
7b. Leaves opposite [— 10.]
7c. Leaves whorled [— 12.]
8a. Leaves with thin sheathing stipules[1b, in NAJADACEAE], p. 2.
8b. Leaves without stipules [— 9.]
9a. Flowers greenish, in a head[SPARGANIACEAE], p. 2.
9b. Flowers pale yellow[1b, in PONTEDERIACEAE], p. 10.
10a. Leaves serrate[2b, in NAJADACEAE], p. 2.
10b. Leaves entire [— 11.]
11a. Leaves 2 cm. long or less[CALLITRICHACEAE], p. 68.
11b. Leaves thread-like, 2-8 cm. long[2a, in NAJADACEAE], p. 2.
11c. Leaves linear to elliptical, more than 2 cm. long[1b, in NAJADACEAE], p. 2.
12a. Leaves in whorls of 3, abruptly widened at the base[2b, in NAJADACEAE], p. 2.
12b. Leaves in whorls of 3, widest near the middle[1b, in HYDROCHARITACEAE], p. 3.
12c. Stems straight and erect, at leaves the flowers emerged; leaves in whorls of 4 or more[2a, in HALORAGIDACEAE], p. 79.
13a. Leaves with numerous small bladders attached, each bladder 1-3 mm. long[LENTIBULARIACEAE], p. 105.
13b. Leaves without bladders [— 14.]
14a. Leaves alternate [— 15.]
14b. Leaves opposite or whorled [— 18.]
15a. Delicate and rare plants growing attached to stones in running water[PODOSTEMACEAE], p. 48.
15b. Plants 2 dm. high or more, with roots in mud or sand [— 16.]
16a. Leaves once-pinnate [— 17.]
16b. Leaves 2-3 times pinnate[15b, in UMBELLIFERAE], p. 81.
16c. Leaves palmately dissected[1b, in RANUNCULACEAE], p. 35.
17a. Taste peppery or mustardy[34, in CRUCIFERAE], p. 45.
17b. Taste not peppery or mustardy[1a, in HALORAGIDACEAE], p. 79.
18a. Leaves pinnately compound[3b, in HALORAGIDACEAE], p. 79.
18b. Leaves palmately compound [— 19.]
19a. Leaves opposite or in whorls of four[119a, in COMPOSITAE], p. 123.
19b. Leaves in whorls of 5-12[CERATOPHYLLACEAE], p. 34.
20a. Plants small, flattened, rounded or ovate, without distinction of stem and leaf; the whole plant floating on or near the surface[LEMNACEAE], p. 9.
20b. Plant attached to the soil, with differentiated stem and leaves [— 21.]
21a. Leaves on long slender stalks, which bear also a cluster of slender tubers near the leaf-base; leaves heart-shape[1b, in GENTIANACEAE], p. 88.
21b. Leaf-stalks without a cluster of tubers [— 22.]
22a. Leaves all basal [— 23.]
22b. Stem-leaves present [— 24.]
23a. Leaves parallel-veined[1b, in ALISMACEAE], p. 3.
23b. Leaves net-veined[1b, in NYMPHAEACEAE], p. 35.
24a. Leaves opposite or whorled [— 25.]
24b. Leaves alternate [— 26.]
25a. Leaves less than 2 cm. long[CALLITRICHACEAE], p. 68.
25b. Leaves more than 2 cm. long[1b, in NAJADACEAE], p. 2.
26a. Leaves attached by the center to the stalk[2b, in NYMPHAEACEAE], p. 35.
26b. Leaves attached by the margin [— 27.]
27a. Leaves parallel-veined [— 28.]
27b. Leaves net-veined, with a single mid-vein; lanceolate or elliptical in outline[29b, in POLYGONACEAE], p. 28.
28a. Leaves not over 2 dm. long[1b, in NAJADACEAE], p. 2.
28b. Leaves very long and grass-like[14a, in GRAMINEAE], p. 5.
29a. Brown, yellow, or white plants, without green color [— 30.]
29b. Plants with normal green color, at least in some parts [— 33.]
30a. Stemless and leafless plants, consisting of flowers only and partly underground[4a, in ARACEAE], p. 8.
30b. Stems climbing on other plants[1b, in CONVOLVULACEAE], p. 91.
30c. Stem and flower-stalks erect, not climbing [— 31.]
31a. Corolla regular; stamens 6-12[1a, in ERICACEAE], p. 84.
31b. Corolla irregular [— 32.]
32a. Sepals and petals each 3; flowers in simple racemes[5a, in ORCHIDACEAE], p. 16.
32b. Sepals 5; corolla of united petals[OROBANCHACEAE], p. 106.
33a. Stem thick and fleshy, leafless, thorny[CACTACEAE], p. 77.
33b. Stem not thorny [— 34.]
34a. Leaves none [— 35.]
34b. Leaves reduced to small scales [— 40.]
34c. Leaves thick and fleshy [— 44.]
34d. Leaves hollow [— 45.]
34e. Leaves small, all basal, bearing large glandular hairs on the upper surface[DROSERACEAE], p. 48.
35a. Stem none, the flowers appearing at or partially beneath the surface of the soil[4a, in ARACEAE], p. 8.
35b. Stem present [— 36.]
36a. Stem freely branched[2a, in LILIACEAE], p. 10.
36b. Stem unbranched, except possibly in the flower-clusters [— 37.]
37a. Flowers greenish or brownish, without obvious colored petals [— 38.]
37b. Flowers with conspicuous white or colored petals [— 39.]
38a. Each flower with 6 small chaffy petals[4, in JUNCACEAE], p. 10.
38b. Petals none; each flower in the axil of a single chaffy bract[2a, in CYPERACEAE], p. 7.
39a. Flowers regular[34a, in LILIACEAE], p. 11.
39b. Flowers irregular[10a, in ORCHIDACEAE], p. 16.
40a. Stem erect, unbranched or with one or two branches only [— 41.]
40b. Stem freely branched [— 42.]
41a. Plants of moist soil, with opposite scales; corolla regular, with 4 petal-like lobes[1a, in GENTIANACEAE], p. 88.
41b. Swamp plants, with a few alternate scales; corolla irregular[LENTIBULARIACEAE], p. 105.
42a. Leaves numerous and close, concealing the stem[2a, in CISTACEAE], p. 74
42b. Leaves spreading, not concealing the stem [— 43.]
43a. Leaf-scales in small clusters; flowers greenish, with 6 petals[2a, in LILIACEAE], p. 10.
43b. Leaf-scales distinctly opposite; petals 5, yellow[7a, in HYPERICACEAE], p. 74.
44a. Sepals 2[3, in PORTULACACEAE], p. 34.
44b. Sepals 4 or 5[CRASSULACEAE], p. 48.
45a. Leaves pitcher-shape, open at the top[SARRACENIACEAE], p. 48.
45b. Leaves tubular, closed at the end[37b, in LILIACEAE], p. 13.

GROUP 3, MONOCOTYLEDONES

1a. Twining plants, with flowers in panicles or racemes[DIOSCOREACEAE], p. 14.
1b. Plants with milky juice[13a, in COMPOSITAE], p. 115.
1c. Plants not twining (some climb by tendrils) and not with milky juice. [— 2.]
2a. Flowers in close spikes or heads, surrounded or subtended by a green or colored bract, the whole resembling a single flower; petals minute or wanting; leaves broad, not grass-like, linear, or sword-shape[ARACEAE], p. 8.
2b. Plants with narrow, linear, grass-like, or sword-shape leaves (a few species of Carex have broader, lanceolate to ovate leaves); flowers greenish, yellowish, or brownish, never brightly colored, and frequently dry or chaffy in texture; perianth small or wanting; individual flowers inconspicuous in size, but sometimes grouped into conspicuous clusters [— 3.]
2c. Plants with leaves of various widths, but the flowers petaloid, i. e., with a white or colored, more or less conspicuous perianth, and never chaffy in texture. In a few cases the flowers are greenish, but the size and conspicuousness of the perianth identifies them in this class [— 9.]
3a. Flowers in the axils of dry, membranous or chaffy scales, which are regularly arranged into spikes or spikelets of uniform size and structure, which are variously grouped or clustered; fruit an achene; grasses and sedges, with joined stems and sheathing leaves, or leafless and the stems not jointed [— 4.]
3b. Flowers not subtended individually by dry, membranous, or chaffy scales, and otherwise not agreeing with 3a [— 5.]
4a. Leaf-sheaths split on the side opposite the leaf; leaves usually 2-ranked, i. e., in 2 longitudinal rows with the third leaf above the first; stems rounded or flat, never triangular, usually hollow[GRAMINEAE], p. 4.
4b. Leaf-sheaths closed into a continuous tube; leaves usually 3-ranked; stems frequently triangular, usually solid[CYPERACEAE], p. 7.
5a. Flowers in dense spikes [— 6.]
5b. Flowers in heads, racemes, or panicles [— 7.]
6a. Spike terminal, with pistillate flowers at the base and staminate ones at the apex[TYPHACEAE], p. 2.
6b. Spike short, apparently lateral, near the apex of the stem[3a, in ARACEAE], p. 8.
7a. Flowers in globose heads which are arranged in spikes, the lowest heads pistillate, the upper staminate; ovary 1-celled[SPARGANIACEAE], p. 2.
7b. Flowers in globose woolly heads terminating leafless unbranched stalks[ERIOCAULACEAE], p. 9.
7c. Flowers in a spike-like raceme; ovaries 3-6, separate or nearly so[JUNCAGINACEAE], p. 3.
7d. Flowers in heads or panicles, all perfect, not woolly, with one ovary [— 8.]
8a. Leaves less than 1 cm. wide, or none; divisions of the perianth 6[JUNCACEAE], p. 10.
8b. Leaves 2 cm. wide or more; petals 5[2a, in UMBELLIFERAE], p. 80.
9a. Flowers regular, with all the petals of approximately the same size and shape [— 10.]
9b. Flowers irregular, with the petals of each flower not of the same size or shape [— 22.]
10a. Ovaries 3 or more, separate or barely united with each other at the base [— 11.]
10b. Ovary one in each flower [— 12.]
11a. Ovaries 3-6 in number; flowers in spikes or racemes; leaves linear[JUNCAGINACEAE], p. 3.
11b. Ovaries more than 6[ALISMACEAE], p. 3.
12a. Flowers or flower-clusters lateral, axillary or apparently so [— 13.]
12b. Flowers or flower-clusters terminal or on leafless stalks [— 14.]
13a. Leaves minute and scale-like; flowers greenish-yellow[2a, in LILIACEAE], p. 10.
13b. Leaves linear, grass-like[3b, in IRIDACEAE], p. 13.
13c. Leaves lanceolate or broader, not grass-like or scale-like[2b, in LILIACEAE], p. 10.
14a. Divisions of the perianth 5-12 cm. long [— 15.]
14b. Divisions of the perianth less than 5 cm. long [— 16.]
15a. Flowers blue, or blue marked with yellow[1a, in IRIDACEAE], p. 15.
15b. Flowers not blue[12a, in LILIACEAE], p. 11.
16a. Flowers solitary [— 17.]
16b. Flowers 2 or more, in some kind of a cluster [— 18.]
17a. Leaves 2, broadly heart-shape, basal, on long stalks[1b, in ARISTOLOCHIACEAE], p. 25.
17b. Leaves not heart-shape 20,[20, in LILIACEAE], p. 12.
18a. Divisions of the perianth (4 to 6) all essentially alike [— 19.]
18b. Perianth differentiated into sepals and 2 or 3 colored petals [— 21.]
19a. Flowers in umbels [— 20.]
19b. Flowers in dense round heads; petals 5[2a, in UMBELLIFERAE], p. 80.
19c. Flowers in spikes, racemes, or panicles[38, in LILIACEAE], p. 13.
20a. Ovary inferior, appearing below the perianth as a swelling at the apex of the stalk; flowers bright yellow; leaves linear[AMARYLLIDACEAE], p. 14.
20b. Ovary inferior; flowers blue or white, terminating a flattened winged leafless flower-stalk[3a, in IRIDACEAE], p. 15.
20c. Ovary superior, i. e., in the center of the flower and separate from the perianth[31, in LILIACEAE], p. 13.
21a. Flowers in dense heads, yellow, 1 cm. wide or smaller[XYRIDACEAE], p. 9.
21b. Flowers in umbels, blue or white, 2 cm. wide or larger[COMMELINACEAE], p. 9.
22a. Flowers blue; ovary superior (defined under [20c]); stamens distinct from the other parts of the flower [— 23.]
22b. Ovary inferior (defined under [20a]); floral structure complex; stamens attached to other parts of the flower and not resembling ordinary stamens in form or structure[ORCHIDACEAE], p. 15.
23a. Leaves triangular-heart-shape at base; marsh plants[1a, in PONTEDERIACEAE], p. 10.
23b. Leaves not heart-shape at base[COMMELINACEAE], p. 9.

GROUP 4, DICOTYLEDONES

1a. Foliage leaves all or principally basal; flower-stalk either completely leafless, or bearing a single pair of opposite leaves only. Bracts and scale-leaves are not considered foliage leaves [— 2.]
1b. Stem-leaves present on the stem, either one or more in number, and not limited to a single opposite pair [— 3.]
2a. Leaves compound [— 7.]
2b. Leaves simple [— 18.]
3a. Stem-leaves all or chiefly opposite or whorled (the bracts of the flower clusters may be alternate) [— 4.]
3b. Stem-leaves all or chiefly alternate [— 5.]
4a. Flowers small and inconspicuous, the perianth none or greenish or chaffy, and never petal-like in appearance [— 50.]
4b. Flowers with a white or colored petal-like perianth [— 66.]
5a. Flowers small and inconspicuous, without any white or colored petal-like perianth [— 118.]
5b. Flowers large or small, but with a white or colored petal-like perianth [— 6.]
6a. Flowers small, not exceeding 3 mm. in length or breadth [— 144.]
6b. Flowers larger, more than 3 mm. in length or breadth [— 166.]
— 7—
7a. Leaves twice to three times compound or dissected [— 8.]
7b. Leaves once-compound [— 11.]
8a. Flowers in racemes[2b, in FUMARIACEAE], p. 41.
8b. Flowers in umbels [— 9.]
9a. Flowers about 3 mm. wide, white or greenish-white [— 10.]
9b. Flowers 10-20 mm. wide, conspicuous[45b, in RANUNCULACEAE], p. 39.
10a. Leaflets 5-15 cm. long[5b, in ARALIACEAE], p. 80.
10b. Leaflets not over 2 cm. long[16a, in UMBELLIFERAE], p. 81.
11a. Leaflets 2[3a, in BERBERIDACEAE], p. 40.
11b. Leaflets three or more [— 12.]
12a. Leaflets entire or very finely toothed [— 13.]
12b. Leaflets coarsely toothed or lobed [— 15.]
13a. Flowers irregular, in dense head-like umbels[37a, in LEGUMINOSAE], p. 61.
13b. Flowers consisting of a greenish or purplish bract wholly or partly enclosing a fleshy spike[2, in ARACEAE], p. 8.
13c. Flowers regular, solitary or in loose clusters [— 14.]
14a. Leaflets reverse heart-shape, not over 2 cm. long[OXALIDACEAE], p. 64.
14b. Leaflets 4-10 cm. long[1c, in GENTIANACEAE], p. 88.
15a. Flowers with colored or white petals and green or colored sepals [— 16.]
15b. Flowers with one kind of perianth only (calyx), with broad and petal-like parts[32, in RANUNCULACEAE], p. 38.
15c. Flowers with white petal-like sepals and small inconspicuous petals[38b, in RANUNCULACEAE], p. 39.
16a. Petals and sepals each 4[31, in CRUCIFERAE], p. 44.
16b. Petals and sepals each 5 or more [— 17.]
17a. Leaves with stipules[ROSACEAE], p. 51.
17b. Leaves without stipules[23b, in RANUNCULACEAE], p. 37.
— 18—
18a. Stem-leaves a single opposite pair (basal leaves may also be present) [— 19.]
18b. Stem-leaves none [— 23.]
19a. Leaves entire [— 20.]
19b. Leaves toothed or lobed [— 21.]
20a. Flowers solitary; leaves broadly kidney-shape[ARISTOLOCHIACEAE], p. 25.
20b. Flowers in racemes; leaves linear or lanceolate[PORTULACACEAE], p. 34.
21a. Flowers in racemes; petals deeply toothed[23b, in SAXIFRAGACEAE], p. 51.
21b. Flowers solitary or few in a cluster; petals entire or nearly so [— 22.]
22a. Petals 5[GERANIACEAE], p. 64.
22b. Petals 6 or more[2b, in BERBERIDACEAE], p.40.
23a. Flowers or flower-clusters sessile, at or partly beneath the surface of the ground[4a, in ARACEAE], p. 8.
23b. Flowers or flower-heads solitary at the ends of the flower-stalks [— 24.]
23b. Flowers or flower-heads numerous or several on each flower-stalk [— 38.]
24a. Flowers yellow [— 25.]
24b. Flowers not yellow [— 29.]
25a. Juice milky[16, in COMPOSITAE], p. 115.
25b. Juice not milky [— 26.]
26a. Aquatic or mud plants, with large entire leaves 1-4 dm. wide[NYMPHAEACEAE], p. 35.
26b. Land plants, with smaller or lobed leaves [— 27.]
27a. Flower-stalk scaly[110, in COMPOSITAE], p. 122.
27b. Flower-stalk bare or with 1 to 2 minute bracts [— 28.]
28a. Flowers regular[10, in RANUNCULACEAE], p. 36.
28b. Flowers irregular, with a spur[3a, in VIOLACEAE], p. 75.
29a. Flowers obviously irregular, with a spur [— 30.]
29b. Flowers regular or nearly so, without a spur [— 31.]
30a. Leaves sessile or nearly so; stamens 2[LENTIBULARIACEAE], p. 105.
30b. Leaves petioled; stamens 5[VIOLACEAE], p. 75.
31a. Flowers 3 mm. wide or smaller; leaves thread-like[16a, in SCROPHULARIACEAE], p. 103.
31b. Flowers 6 mm. wide or larger [— 32.]
32a. Ovary 1 [— 33.]
32b. Ovaries numerous [— 37.]
33a. Leaves lobed or cleft [— 34.]
33b. Leaves entire or toothed [— 35.]
34a. Leaves deeply 2-cleft; stamens 8[3a, in BERBERIDACEAE], p. 40.
34b. Leaf 1, palmately lobed; stamens numerous[1a, in PAPAVERACEAE], p. 41.
35a. Flowers dull red[ARISTOLOCHIACEAE], p. 25.
35b. Flowers white or pinkish [— 36.]
36a. Leaves entire; stamens with good anthers 5[13, in SAXIFRAGACEAE], p. 50.
36b. Leaves minutely toothed; stamens 8-10[14a, in ERICACEAE], p. 85.
37a. Leaves lobed or divided[RANUNCULACEAE], p. 35.
37b. Leaves crenate or toothed[64a, in ROSACEAE], p. 56.
— 38—
38a. Flowers of the composite type, with several or many small flowerets closely aggregated into a dense head surrounded by a calyx-like involucre of small bracts[10, in COMPOSITAE]. p. 114.
38b. Flowers separate; variously clustered, but never crowded into involucred heads [— 39.]
39a. Flowers in dense close spikes [— 40.]
39b. Flowers in open loose clusters [— 42.]
40a. Flower-stalk leafless below the spike[PLANTAGINACEAE], p. 107.
40b. Flower-stalk with several bracts [— 41.]
41a. Leaves entire[9c, in ORCHIDACEAE], p. 16.
41b. Leaves toothed[6a, in SCROPHULARIACEAE], p. 102.
42a. Flowers in umbels [— 43.]
42b. Flowers in racemes, panicles, flat-topped clusters, or merely 1 or 2 [— 45.]
43a. Leaves almost round, peltate, palmately veined[3a, in UMBELLIFERAE], p. 80.
43b. Leaves at least twice as long as broad, with a single mid-vein [— 44.]
44a. Stamens 5[PRIMULACEAE], p. 87.
44b. Stamens 10[15, in ERICACEAE], p. 85.
45a. Leaves cylindrical, hollow, obtuse.[1a, in LOBELIACEAE], p. 113.
45b. Leaves beset on the upper side with long glandular hairs; bog plant with flowers in racemes[DROSERACEAE], p. 48.
45c. Leaves flat, pubescent or smooth, but not with long glandular hairs [— 46.]
46a. Sepals and petals each 4[53, in CRUCIFERAE], p. 46.
46b. Sepals and petals each 5 [— 47.]
46c. Sepals 6; petals none; flowers minute, green; leaves frequently lobed at the base[4, in POLYGONACEAE], p. 25.
47a. Petals united with each other in an irregular corolla[LENTIBULARIACEAE], p. 105.
47b. Petals separate from each other [— 48.]
48a. Stamens 10; style 1[ERICACEAE], p. 84.
48b. Stamens 5 or 10; styles 2[SAXIFRAGACEAE], p. 49.
48c. Stamens and pistils each very numerous [— 49.]
49a. Flowers white[64a, in ROSACEAE], p. 56.
49b. Flowers yellow[13a, in RANUNCULACEAE], p. 36.
— 50—
50a. Leaves compound or deeply lobed [— 51.]
50b. Leaves entire or toothed [— 54.]
51a. Flowers in axillary racemes, spikes, or panicles[URTICACEAE], p. 23.
51b. Flowers terminal, or in terminal clusters [— 52.]
52a. Flowers in umbels; leaves palmately compound[ARALIACEAE], p. 80.
52b. Flowers in racemes or spikes, or solitary [— 53.]
53a. Leaves deeply pinnatifid; swamp plants with flowers in spikes or solitary[HALORAGIDACEAE], p. 79.
53b. Leaves lobed, or irregularly pinnately cut or dissected; weedy plants with flowers in racemes[2, in COMPOSITAE], p. 114.
54a. Juice milky[3, in EUPHORBIACEAE], p. 67.
54b. Juice not milky or colored [— 55.]
55a. Leaves whorled [— 56.]
55b. Leaves all opposite [— 58.]
56a. Aquatic or mud plants with erect stems[2a, in HALORAGIDACEAE], p. 79.
56b. Prostrate weedy terrestrial plants[AIZOACEAE], p. 31.
56c. Erect or ascending terrestrial plants [— 57.]
57a. Leaves more than 2.5 cm. long[4a, in CORNACEAE], p. 83.
57b. Leaves 2 cm. long or less[3a, in PRIMULACEAE], p. 87.
58a. Flowers in terminal or axillary spikes, racemes, or other clusters [— 59.]
58b. Flowers solitary or few in the axils of the leaves [— 61.]
59a. Leaves less than 5 mm. long[1a, in GENTIANACEAE], p. 88.
59b. Leaves more than 2 cm. long [— 60.]
60a. Inflorescence chiefly terminal, panicled[2, in COMPOSITAE], p. 114.
60b. Inflorescence chiefly axillary[URTICACEAE], p. 23.
61a. Flowers on long pedicels[2, in CARYOPHYLLACEAE], p. 31.
61b. Flowers on short pedicels or sessile [— 62.]
62a. Stem erect, repeatedly branched; leaves linear to oblong[ILLECEBRACEAE], p. 31.
62b. Stem decumbent or prostrate [— 63.]
63a. Leaves round, ovate, or kidney-shape, rounded at the base, crenate or lobed[12a, in SAXIFRAGACEAE], p. 50.
63b. Leaves of a narrower shape, entire, tapering toward the base [— 64.]
64a. Principal leaves 2-3 cm. long[1a, in ONAGRACEAE], p. 78.
64b. Principal leaves 1 cm. long or less [— 65.]
65a. Petals present[ELATINACEAE], p. 74.
65b. Petals none[CALLITRICHACEAE], p. 68.
— 66—
66a. Plants of the composite type, with several or many small flowerets closely aggregated into a dense head surrounded or subtended by a calyx-like involucre of small bracts [— 67.]
66b. Flowers solitary or variously clustered, but not in involucred heads [— 70.]
67a. Involucre of 4 conspicuous white bracts, much larger than the small flower-cluster[4a, in CORNACEAE], p. 83.
67b. Involucral bracts green or somewhat colored [— 68.]
68a. Stem more or less prickly[DIPSACACEAE], p. 112.
68b. Stem and leaves not prickly [— 69.]
69a. Stem square; foliage aromatic when crushed[LABIATAE], p. 95.
69b. Stem not square; foliage not with the odor of mint[COMPOSITAE], p. 113.
70a. The conspicuous portion of the perianth[1] composed of separate parts [— 71.]
70b. The conspicuous portion of the perianth[1] composed of united parts [— 97.]
71a. Stem-leaves compound, or cleft to the very base [— 72.]
71b. Stem-leaves simple [— 78.]
72a. Stamens more than 10 in each flower [— 73.]
72b. Stamens 5-10 in each flower [— 75.]
73a. Ovary 1 in each flower[2a, in PAPAVERACEAE], p. 41.
73b. Ovaries several in each flower [— 74.]
74a. Leaves pinnately compound[68a, in ROSACEAE], p. 57.
74b. Leaves palmately compound[RANUNCULACEAE], p. 35.
75a. Stamens 6[31, in CRUCIFERAE], p. 44.
75b. Stamens 5 or 10 [— 76.]
76a. Leaflets reverse heart-shape; flowers yellow[OXALIDACEAE], p. 64.
76b. Leaflets not reverse heart-shape; flowers white, greenish, or pink [— 77.]
77a. Flowers greenish or white, about 2 mm. broad[ARALIACEAE], p. 80.
77b. Flowers 5 mm. broad or larger[GERANIACEAE], p. 64.
78a. Juice milky [— 79.]
78b. Juice not milky [— 80.]
79a. A 3-lobed ovary with 3 short styles visible in some of the flowers[EUPHORBIACEAE], p. 66.
79b. Ovaries 2 in the center of each flower (sometimes concealed by other organs); sepals and petals each 5 [— 104.]
80a. Perianth with one circle of parts only [— 81.]
80b. Each flower with both calyx and corolla [— 82.]
81a. Stem prostrate; flowers only 2 mm. broad[AIZOACEAE], p. 31.
81b. Stem erect; flowers at least 20 mm. wide[4a, in CORNACEAE], p. 83.
82a. Petals 2 or 4 [— 83.]
82b. Petals 3[22, in LILIACEAE], p. 12.
82c. Petals 5 or 6 [— 84.]
83a. Leaves with 3-5 principal veins[MELASTOMACEAE], p. 77.
83b. Leaves with 1 principal mid-vein[ONAGRACEAE], p. 78.
84a. Leaves palmately lobed [— 85.]
84b. Leaves entire or toothed, or with 1-2 small lobes near the base only [— 86.]
85a. Petals entire or notched at the end[GERANIACEAE], p. 64.
85b. Petals conspicuously fringed[23b, in SAXIFRAGACEAE], p. 51.
86a. Ovary 1 [— 87.]
86b. Ovaries 2, surrounded and concealed by other organs[ASCLEPIADACEAE], p. 90.
86c. Ovaries 4-5[2b, in CRASSULACEAE], p. 48.
87a. Leaves dotted with translucent dots (easily seen when the leaf is held to the light)[HYPERICACEAE], p. 73.
87b. Leaves not dotted with translucent dots [— 88.]
88a. Leaves only 1-3 mm. long, closely appressed and concealing the stem[2a, in CISTACEAE], p. 74.
88b. Leaves larger, not concealing the stem [— 89.]
89a. Style 1 or none [— 90.]
89b. Styles 2 to 7 [— 94.]
90a. Stamens 5 [— 91.]
90b. Stamens 10 [— 92.]
90c. Stamens neither 5 nor 10 [— 93.]
91a. Flowers blue, sessile in terminal spikes with leaf-like bracts[LYTHRACEAE], p. 77.
91b. Flowers not in terminal bracted spikes[PRIMULACEAE], p. 87.
92a. Leaves entire[LYTHRACEAE], p. 77.
92b. Leaves toothed or crenate[ERICACEAE], p. 84.
93a. Flowers irregular; petals 3[POLYGALACEAE], p. 65.
93b. Flowers regular; petals 5 or more[LYTHRACEAE], p. 77.
94a. Sepals 2, partly attached to the ovary[PORTULACACEAE], p. 34.
94b. Sepals 5, free from the ovary [— 95.]
95a. Stamens 5 [— 96.]
95b. Stamens not 5[CARYOPHYLLACEAE], p. 31.
96a. Flowers blue or yellow[LINACEAE], p. 63.
96b. Flowers white or pinkish[CARYOPHYLLACEAE], p. 31.
— 97—
97a. Perianth with but one circle of floral leaves [— 98.]
97b. Perianth consisting of both calyx and corolla [— 101.]
98a. Flowers small, in dense heads subtended by conspicuous bracts [— 99.]
98b. Flowers 2-5, in a colored spreading 5-lobed involucre[NYCTAGINACEAE], p. 31.
98c. Flowers in various sorts of clusters or solitary, but never in heads with a conspicuous involucre [— 100.]
99a. Bracts 4, white and conspicuous; stem not thorny[4a, in CORNACEAE], p. 83.
99b. Bracts green; stem thorny[DIPSACACEAE], p. 112.
100a. Stamens 3[VALERIANACEAE], p. 111.
100b. Stamens 4 or 5[RUBIACEAE], p. 108.
101a. Anthers more numerous than the lobes of the corolla [— 102.]
101b. Anthers just as many as the lobes of the corolla [— 103.]
101c. Anthers fewer than the lobes of the corolla [— 110.]
102a. Leaves simple[POLYGALACEAE], p. 65.
102b. Leaves compound with 3 leaflets[OXALIDACEAE], p. 64.
102c. Leaves finely dissected; stems climbing[2a, in FUMARIACEAE], p. 41.
103a. Ovaries 2 [— 104.]
103b. Ovary 1, but very deeply 4-lobed, with a single style[LABIATAE], p. 95.
103c. Ovary 1, not deeply lobed [— 105.]
104a. Stamens united, surrounding and more or less concealing the ovaries, and not resembling ordinary stamens[ASCLEPIADACEAE], p. 90.
104b. Stamens separate, of ordinary structure[APOCYNACEAE], p. 90.
105a. Ovary inferior, appearing as a swelling below the calyx at the apex of the pedicel [— 106.]
105b. Ovary superior, located in the center of the flower [— 107.]
106a. Corolla 3-4-lobed[RUBIACEAE], p. 108.
106b. Corolla 5-lobed[3b, in CAPRIFOLIACEAE], p. 109.
107a. Leaves toothed or deeply cut[VERBENACEAE], p. 99.
107b. Leaves entire [— 108.]
108a. A stamen in front of the middle of each petal[PRIMULACEAE], p. 87.
108b. Stamens located between the petals or lobes of the corolla, or else so far down in the tubular corolla that their position is not easily ascertained [— 109.]
109a. Corolla salver-form, with a very slender tube, and abruptly spreading lobes[POLEMONIACEAE], p. 92.
109b. Corolla salver-form, with a wide tube and fringed blue petals[GENTIANACEAE], p. 88.
109c. Corolla rotate, funnel-form, or bell-shape[GENTIANACEAE], p. 88.
110a. Ovary deeply 4-lobed, appearing like 4 separate ovaries; style 1[LABIATAE], p. 95.
110b. Ovary not 4-lobed [— 111.]
111a. Stamens 2 [— 112.]
111b. Stamens 3[VALERIANACEAE], p. 111.
111c. Stamens 4 [— 113.]
112a. Flowers in dense heads[1a, in ACANTHACEAE], p. 107.
112b. Flowers solitary or in loose clusters[SCROPHULARIACEAE], p. 101.
113a. Corolla distinctly 2-lipped and irregular [— 114.]
113b. Corolla not distinctly 2-lipped, its 5 lobes all alike or nearly so [— 115.]
114a. Calyx 2-lipped; the upper lip with 3 awl-shape teeth, the lower with 2 short teeth; flowers in slender terminal spikes[PHRYMACEAE], p. 107.
114b. Calyx not obviously 2-lipped, its teeth equal or nearly so[SCROPHULARIACEAE], p. 101.
115a. Flowers sessile or nearly so, in spikes [— 116.]
115b. Flowers in nodding pairs at the top of a slender stalk[3a, in CAPRIFOLIACEAE], p. 109.
115c. Flowers solitary or in clusters; not in spikes or nodding pairs [— 117.]
116a. Corolla not over 1 cm. long[VERBENACEAE], p. 99.
116b. Corolla 1.5 cm. long or more[SCROPHULARIACEAE], p. 101.
117a. Calyx-lobes 15-25 mm. long; flowers blue, 3-5 cm. long; calyx without an obvious tube[2, in ACANTHACEAE], p. 107.
117b. Calyx-lobes united below into an obvious calyx-tube[SCROPHULARIACEAE], p. 101.
— 118—
118a. Leaves deeply lobed, compound, or dissected [— 119.]
118b. Leaves simple and not deeply lobed [— 129.]
119a. Leaves once-pinnately compound or lobed [— 120.]
119b. Leaves once-palmately compound or lobed [— 124.]
119c. Leaves dissected or 2-3 times compound [— 125.]
120a. Leaves merely lobed [— 121.]
120b. Leaves actually compound [— 123.]
121a. Flowers axillary; marsh or swamp plants[HALORAGIDACEAE], p. 79.
121b. Flowers in terminal clusters [— 122.]
122a. Stamens 2-6; taste mustard-like[52b, in CRUCIFERAE], p. 46.
122b. Stamens 10 or more[RESEDACEAE], p. 48.
123a. Leaflets entire[LIMNANTHACEAE], p. 68.
123b. Leaflets serrate[70a, in ROSACEAE], p. 57.
124a. Flowers solitary[31a, in RANUNCULACEAE], p. 38.
124b. Flowers in dense terminal umbels or heads[UMBELLIFERAE], p. 80.
124c. Flowers in terminal racemes[2a, in COMPOSITAE], p. 114.
124d. Flowers in axillary spikes or panicles[9b, in URTICACEAE], p. 24.
125a. Leaves merely dissected, not truly compound with distinct leaflets [— 126.]
125b. Leaves truly compound, with distinct petiolate leaflets [— 127.]
126a. Flowers in axillary clusters[CHENOPODIACEAE], p. 28.
126b. Flowers in terminal clusters[COMPOSITAE], p. 113.
127a. Stamens 5; flowers in umbels [— 128.]
127b. Stamens 6; flowers in small clusters[3b, in BERBERIDACEAE], p. 40.
127c. Stamens many; flowers in racemes or panicles[RANUNCULACEAE], p. 35.
128a. Styles 5[ARALIACEAE], p. 80.
128b. Styles 2[UMBELLIFERAE], p. 80.
129a. Flowers in dense cottony heads; plants more or less white-woolly[79, in COMPOSITAE], p. 120.
129b. Pistillate flowers in an ovoid spiny involucre, ripening into a bur[3a, in COMPOSITAE], p. 114.
129c. Flowers minute, subtended by palmately cleft axillary bracts[1a, in EUPHORBIACEAE], p. 66.
129d. Plants without any of the preceding characters [— 130.]
130a. Plants with milky or colored juice[10, in EUPHORBIACEAE], p. 67.
130b. Plants with tendrils, at least on the upper leaves[4a, in LILIACEAE], p. 11.
130c. Plants of nettle-like character, with stinging hairs[8b, in URTICACEAE], p. 24.
130d. Plants with sheathing stipules, surrounding the stem above the base of each leaf[POLYGONACEAE], p. 25.
130e. Plants with smooth, pale, juicy, almost translucent stems[12a, in URTICACEAE], p. 24.
130f. Plants without any of the preceding structures or habits [— 131.]
131a. Flowers axillary, solitary or in few-flowered clusters [— 132.]
131b. Flowers in terminal, or terminal and axillary clusters [— 138.]
132a. Leaves linear[CHENOPODIACEAE], p. 28.
132b. Leaves of a broader shape than linear [— 133.]
133a. Flower-clusters with bracts as long as or longer than the flowers [— 134.]
133b. Flowers without conspicuous bracts [— 135.]
134a. Leaves broadest below the middle[8a, in URTICACEAE], p. 24.
134b. Leaves broadest above the middle[2, in AMARANTHACEAE], p. 30.
135a. Principal leaves 3 cm. long or more [— 136.]
135b. Principal leaves 2.5 cm. long or less [— 137.]
136a. Flowers nodding in the axils of the leaves[1a, in VIOLACEAE], p. 75.
136b. Flowers erect in the axils[2a, in ONAGRACEAE], p. 78.
137a. Leaves narrowly oblong[1a, in HALORAGIDACEAE], p. 79.
137b. Leaves roundish and somewhat heart-shape[12a, in SAXIFRAGACEAE], p. 50.
138a. Flowers in racemes or simple spikes [— 139.]
138b. Flowers in panicles or other branched clusters [— 141.]
139a. Leaves toothed or lobed[52b, in CRUCIFERAE], p. 46.
139b. Leaves entire [— 140.]
140a. Flowers sessile; leaves heart-shape[PIPERACEAE], p. 19.
140b. Flowers pedicelled; leaves obovate[8b, in PRIMULACEAE], p. 87.
141a. Individual flowers distinct from each other, on pedicels [— 142.]
141b. Individual flowers crowded in close clusters, or separate and sessile [— 143.]
142a. Leaves finely serrate[3b, in CRASSULACEAE], p. 49.
142b. Leaves entire[1b, in CISTACEAE], p. 74.
143a. Flower-clusters mingled with sharp-pointed bracts[AMARANTHACEAE], p. 30.
143b. Flower-clusters without bracts, or (rarely) with bracts which are not sharp-pointed[CHENOPODIACEAE], p. 28.
— 144—
144a. Juice not milky [— 145.]
144b. Juice milky; apparent flowers consisting of a few white or colored petal-like bracts, inclosing a few inconspicuous flowers without petals. In some of them a 3-lobed ovary with 3 styles may be plainly seen
145a. Plants of the composite type, with several or many small flowerets closely aggregated into a dense head subtended by a calyx-like involucre of small bracts [— 146.][EUPHORBIACEAE], p. 66.
145b. Flowers solitary or in clusters, but not in involucred heads [— 147.]
146a. Leaves compound with 3 leaflets; stipules present[LEGUMINOSAE], p. 58.
146b. Stipules none[COMPOSITAE], p. 113.
147a. Leaves compound or deeply lobed [— 148.]
147b. Leaves simple and not deeply lobed [— 154.]
148a. Flowers irregular[LEGUMINOSAE], p. 58.
148b. Flowers regular [— 149.]
149a. Petals 3[LIMNANTHACEAE], p. 68.
149b. Petals 4 [— 150.]
149c. Petals 5 or more [— 151.]
150a. Stamens 4[70a, in ROSACEAE], p. 57.
150b. Stamens 6[CRUCIFERAE], p. 42.
150c. Stamens numerous[43, in RANUNCULACEAE], p. 39.
151a. Flowers in heads or umbels [— 152.]
151b. Flowers in slender spikes or racemes [— 153.]
152a. Styles 2[UMBELLIFERAE], p. 80.
152b. Styles 5[ARALIACEAE], p. 80.
153a. Leaves ternately compound[43, in RANUNCULACEAE], p. 39.
153b. Leaves once-pinnately compound[50b, in ROSACEAE], p. 55.
154a. Flowers irregular [— 155.]
154b. Flowers regular [— 156.]
155a. Stamens 2[40b, in SCROPHULARIACEAE], p. 104.
155b. Stamens 5 or 10[SAXIFRAGACEAE], p. 49.
155c. Stamens 6 or 8[POLYGALACEAE], p. 65.
156a. With sheathing stipules surrounding the stem at the base of each leaf[POLYGONACEAE], p. 24.
156b. Stipules not encircling the stem, or none [— 157.]
157a. Petals 3[CISTACEAE], p. 74.
157b. Petals 4 [— 158.]
157c. Petals 5 [— 161.]
158a. Stamens 2 [— 159.]
158b. Stamens 6[CRUCIFERAE], p. 42.
158c. Stamens 8 [— 160.]
159a. Corolla perfectly regular; flowers in terminal clusters without bracts, becoming racemes; taste peppery[52a, in CRUCIFERAE], p. 46.
159b. Corolla slightly irregular; flowers in bracted clusters, or axillary; taste not peppery[40b, in SCROPHULARIACEAE], p. 104.
160a. Delicate trailing evergreen, with flowers solitary in the axils and nearly or quite hidden beneath the leaves[22b, in ERICACEAE], p. 85.
160b. Erect or nearly so; flowers in terminal clusters[12b, in ONAGRACEAE], p. 78.
161a. Leaves sword-shape, finely parallel-veined, with bristly margins[2a, in UMBELLIFERAE], p. 80.
161b. Leaves not sword-shape [— 162.]
162a. Leaves toothed or lobed [— 163.]
162b. Leaves entire [— 164.]
163a. Stems creeping[2b, in UMBELLIFERAE], p. 80.
163b. Stems erect or nearly so[SAXIFRAGACEAE], p. 49.
164a. Flowers in open panicles; leaves principally basal[SAXIFRAGACEAE], p. 49.
164b. Flowers in rounded or flattened clusters; leaves principally on the stem[SANTALACEAE], p. 24.
164c. Flowers in racemes, which become elongated at maturity [— 165.]
165a. Foliage glabrous[8b, in PRIMULACEAE], p. 87.
165b. Foliage pubescent[BORAGINACEAE], p. 93.
— 166—
166a. Juice milky or colored [— 167.]
166b. Juice watery, not colored [— 172.]
167a. Apparent flowers consisting of a few petal-like bracts, inclosing a few inconspicuous flowers without petals. In some of them a 3-lobed ovary with 3 styles may be seen[EUPHORBIACEAE], p. 66.
167b. Plants of the composite type, with several or many small flowerets closely aggregated in dense heads subtended by a calyx-like involucre of small bracts[11, in COMPOSITAE], p. 115.
167c. Flowers never aggregated in involucred clusters resembling a single flower [— 168.]
168a. Corolla very irregular; stamens protruding[LOBELIACEAE], p. 113
168b. Corolla regular [— 169.]
169a. Stamens with ordinary visible anthers; ovary 1 [— 170.]
169b. Stamens so grown together and to the stigma as to be almost unrecognizable; ovaries 2[ASCLEPIADACEAE], p. 90.
170a. Petals separate[PAPAVERACEAE], p. 41.
170b. Petals united [— 171.]
171a. Stamens attached to the tube of the corolla[CONVOLVULACEAE], p. 91.
171b. Stamens attached at the very base of the corolla[CAMPANULACEAE], p. 112.
172a. Plants of the composite type, with several or many small flowerets closely aggregated into dense heads subtended by a calyx-like involucre of small bracts [— 173.]
172b. Flowers solitary or clustered, but not in involucred heads [— 174.]
173a. True composites, without a normal calyx[COMPOSITAE], p. 113.
173b. A normal calyx with each floweret; leaves compound with 3 leaflets[LEGUMINOSAE], p. 58.
174a. Flowers irregular, i. e., the conspicuous lobes of the perianth unlike in size or shape [— 175.]
174b. Flowers regular [— 185.]
175a. Stamens 2 or 4[SCROPHULARIACEAE], p. 101.
175b. Stamens 5 [— 176.]
175c. Stamens 6 [— 181.]
175d. Stamens 8; leaves simple[POLYGALACEAE], p. 65.
175e. Stamens 10; leaves usually compound[LEGUMINOSAE], p. 58.
175f. Stamens more than 10 [— 183.]
176a. Petals separate [— 177.]
176b. Petals united [— 179.]
177a. Flowers greenish or purplish, in a panicle[SAXIFRAGACEAE], p. 49.
177b. Flowers white or purplish, in compound umbels[UMBELLIFERAE], p. 80.
177c. Flowers solitary, or in few-flowered clusters [— 178.]
178a. Flowers blue, yellow, or white, in spring[VIOLACEAE], p. 75.
178b. Flowers red-orange or yellow, in summer[BALSAMINACEAE], p. 71.
178c. Flowers small and greenish, in spring[1a, in VIOLACEAE], p. 75.
179a. Anthers united; stamens protruding from the very irregular corolla[LOBELIACEAE], p. 113.
179b. Anthers separate; corolla almost regular [— 180.]
180a. Corolla rotate; some or all filaments hairy[2, in SCROPHULARIACEAE], p. 101.
180b. Corolla funnel-form, dull yellow and purple; filaments not hairy[12a, in SOLANACEAE], p. 101.
180c. Corolla funnel-form, blue or violet; filaments not hairy[7b, in BORAGINACEAE], p. 94.
181a. Leaves compound or dissected[FUMARIACEAE], p. 41.
181b. Leaves simple [— 182.]
182a. Flowers solitary[ARISTOLOCHIACEAE], p. 25.
182b. Flowers in spikes, heads, or racemes[POLYGALACEAE], p. 65.
183a. Leaves truly compound [— 184.]
183b. Leaves palmately cleft; flowers 15 mm. wide or larger[6a, in RANUNCULACEAE], p. 36.
183c. Leaves irregularly cleft; flowers about 5 mm. wide[RESEDACEAE], p. 48.
184a. Petals prolonged backward into hollow spurs[6b, in RANUNCULACEAE], p. 36.
184b. Petals not prolonged into spurs[CAPPARIDACEAE], p. 47.
— 185—
185a. Perianth consisting of one circle of parts only (usually considered to be the calyx) [— 186.]
185b. Perianth consisting of both calyx and corolla [— 192.]
186a. Leaves with sheathing stipules encircling the stem above the base of every leaf[POLYGONACEAE], p. 25.
186b. Leaves without sheathing stipules [— 187.]
187a. Leaves entire [— 188.]
187b. Leaves toothed, lobed, or compound [— 190.]
188a. Stamens 5[SANTALACEAE], p. 24.
188b. Stamens 6 [— 189.]
188c. Stamens 10[PHYTOLACCACEAE], p. 30.
189a. Perianth-lobes 3; perianth-tube curved[ARISTOLOCHIACEAE], p. 25.
189b. Perianth-lobes 6, spreading[4a, in LILIACEAE], p. 11.
190a. Stamens 5[UMBELLIFERAE], p. 80.
190b. Stamens 6 [— 191.]
190c. Stamens more than 6[RANUNCULACEAE], p. 35.
191a. Climbing plant with heart-shape perianth[2a, in FUMARIACEAE], p. 41.
191b. Erect plant, with spreading perianth[3b, in BERBERIDACEAE], p. 40.
192a. Corolla composed of united petals [— 193.]
192b. Corolla composed of separate petals [— 208.]
193a. Stamens 2 or 4[SCROPHULARIACEAE], p. 101.
193b. Stamens 3; climbing vines[CUCURBITACEAE], p. 112.
193c. Stamens 5 [— 194.]
193d. Stamens 6[2a, in FUMARIACEAE], p. 41.
193e. Stamens 8[22b, in ERICACEAE], p. 85.
193f. Stamens 10 [— 207.]
193g. Stamens very numerous[MALVACEAE], p. 72.
194a. Ovaries 2; flowers orange-red, in umbels[7a, in ASCLEPIADACEAE], p. 91.
194b. Ovary 1, deeply 4-lobed; flowers in racemes[BORAGINACEAE], p. 93.
194c. Ovary 1, not deeply lobed [— 195.]
195a. Climbing or scrambling vines [— 196.]
195b. Not climbing or scrambling [— 198.]
196a. Flowers about 1 cm. wide [— 197.]
196b. Flowers 2-8 cm. wide[CONVOLVULACEAE], p. 91.
197a. Leaves 1 cm. wide or less[2b, in CAMPANULACEAE], p. 112.
197b. Leaves 2 cm. wide or more[4a, in SOLANACEAE], p. 100.
198a. Flowers solitary, either terminal or axillary [— 199.]
198b. Flowers in terminal clusters [— 201.]
199a. Calyx concealed by 2 bracts[CONVOLVULACEAE], p. 91.
199b. Calyx not completely concealed by bracts [— 200.]
200a. Ovary inferior, appearing as a swelling below the calyx at the base of the flower, 3-celled; stigma 3-lobed[CAMPANULACEAE], p. 112.
200b. Ovary superior, located in the center of the flower[SOLANACEAE], p. 100.
201a. Some or all filaments hairy [— 202.]
201b. Filaments not hairy [— 203.]
202a. Leaves lobed or divided[HYDROPHYLLACEAE], p. 93.
202b. Leaves not lobed[2, in SCROPHULARIACEAE], p. 101.
203a. Anthers close together, longer than the filaments[2, in SOLANACEAE], p. 100.
203b. Anthers separate from each other [— 204.]
204a. Leaves compound or very deeply lobed [— 205.]
204b. Leaves simple or with shallow lobes only [— 206.]
205a. Leaf-segments linear or oblong, irregular[HYDROPHYLLACEAE], p. 93.
205b. Leaves truly compound with separate leaflets[1a, in POLEMONIACEAE], p. 92.
206a. Flowers greenish-yellow[SOLANACEAE], p. 100.
206b. Flowers blue, violet, white, or intermediate tints[CAMPANULACEAE], p. 112.
207a. Leaves simple[ERICACEAE], p. 84.
207b. Leaves compound[OXALIDACEAE], p. 64.
— 208—
208a. Petals 4 [— 209.]
208b. Petals 5 [— 212.]
208c. Petals 6 or more [— 227.]
209a. Stamens 4 or 8 [— 210.]
209b. Stamens 6, 4 long and 2 short[CRUCIFERAE], p. 42.
209c. Stamens 9 or more[CAPPARIDACEAE], p. 47.
210a. Leaves compound[ROSACEAE], p. 51.
210b. Leaves simple [— 211.]
211a. Ovary 1, inferior, appearing as a swelling below the calyx[ONAGRACEAE], p. 78.
211b. Ovaries 4 or 5, in the center of the flower[CRASSULACEAE], p. 48.
212a. Stamens with good anthers 5 [— 213.]
212b. Stamens 6 to 10 [— 217.]
212c. Stamens more than 10 [— 222.]
213a. Flowers solitary, terminating the stem[12b, in SAXIFRAGACEAE], p. 50.
213b. Flowers axillary, solitary or in small clusters [— 214.]
213c. Flowers several, in loose irregular terminal clusters; leaves simple[LINACEAE], p. 63.
213d. Flowers in slender spike-like racemes; leaves compound[50b, in ROSACEAE], p. 55.
213e. Flowers in panicles[20a, in SAXIFRAGACEAE], p. 50.
213f. Flowers in umbels [— 216.]
214a. Leaves compound[25b, in LEGUMINOSAE], p. 60.
214b. Leaves simple [— 215.]
215a. Flowers blue or yellow, erect or spreading[LINACEAE], p. 63.
215b. Flowers greenish, nodding[1a, in VIOLACEAE], p. 75.
216a. Flowers pink or purple[GERANIACEAE], p. 64.
216b. Flowers yellow or white[UMBELLIFERAE], p. 80.
217a. Leaves compound with 3 leaflets [— 218.]
217b. Leaves pinnately compound [— 219.]
217c. Leaves deeply palmately lobed[GERANIACEAE], p. 64.
217d. Leaves simple and not deeply lobed [— 220.]
218a. Leaflets reverse heart-shape; flowers yellow[OXALIDACEAE], p. 64.
218b. Leaflets taper-pointed; flowers white or pink[73, in ROSACEAE], p. 57.
219a. Leaflets entire[24, in LEGUMINOSAE], p. 60.
219b. Leaflets toothed[50b, in ROSACEAE], p. 55.
220a. Prostrate plants, with thick, fleshy, entire leaves[3, in PORTULACACEAE], p. 34.
220b. Bushy branched plants, with small gray leaves concealing the stem[2a, in CISTACEAE], p. 74.
220c. Erect or spreading plants [— 221.]
221a. Ovary 1, style 1[4a, in ERICACEAE], p. 84.
221b. Ovary with 2 distinct styles[SAXIFRAGACEAE], p. 49.
221c. Ovaries 5; styles 5[CRASSULACEAE], p. 48.
222a. Stamens united by their filaments into a tube[MALVACEAE], p. 72.
222b. Stamens separate from each other [— 223.]
223a. Leaves with stipules; ovaries more than 1[ROSACEAE], p. 51.
223b. Leaves without stipules [— 224.]
224a. Leaves toothed, deeply lobed, or compound[RANUNCULACEAE], p. 35.
224b. Leaves entire [— 225.]
225a. Ovaries numerous[RANUNCULACEAE], p. 35.
225b. Ovary 1 [— 226.]
226a. Sepals 2[PORTULACACEAE], p. 34.
226b. Sepals 3 or 5[CISTACEAE], p. 74.
— 227—
227a. Leaves entire[LYTHRACEAE], p. 77.
227b. Leaves lobed, divided, dissected, or compound [— 228.]
228a. Flowers in slender racemes[RESEDACEAE], p. 48.
228b. Flowers solitary or clustered, but not in slender racemes [— 229.]
229a. Stamens 6[3b, in BERBERIDACEAE], p. 40.
229b. Stamens numerous[RANUNCULACEAE], p. 35.