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Group 3: Monocots
See list of 37 families in this group-
1a. Plants thalloid, not differentiated into stems and leaves, 0.5–15 mm long, free floating on or near the surface of water [Fig. 61] (in part)
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1b. Plants not thalloid, differentiated into stems and leaves, usually much longer or taller; habit various, but when floating usually rooted in the substrate
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2a. Flowers replaced by, or modified into, vegetative propagules
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3a. Plants from a conspicuous bulb [Fig. 60], with a strong odor of onion or garlic; stems ± scapose (in part)
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3b. Plants without a conspicuous, bulbous base, lacking the odor of onion; stems with leaves
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4a. Leaves terete or elliptic in cross-section and with complete, transverse septa (in part)
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4b. Leaves flat, without complete transverse septa (though partial septa may be present)
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5a. Plants submersed aquatics, with flaccid underwater leaves (in part)
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5b. Plants terrestrial, with firmer leaves
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6a. Inflorescence a panicle [Fig. 259]; leaves arranged in 2 ranks, with collar-like ligules (in part)
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6b. Inflorescence a spike, with flowers in an umbel-like cluster; leaves arranged in 3 ranks, with ligules, but these inconspicuous and not collar-like (in part)
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2b. Flowers not replaced by vegetative bulbils
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7a. Gynoecium composed of 2 or more distinct carpels and each carpel with a single stigma [Fig. 301]; plants aquatic or of hydric habitats
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8a. Leaf blades triquetrous in cross-section; perianth petaloid, composed of green-pink sepals and pink petals; flowers with 9 stamens and 6 carpels
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8b. Leaf blades either flat, ± terete, or capillary; perianth either absent, entirely sepaloid, or composed of green sepals and white petals; flowers with 1–many stamens and 3–many carpels, but not consistently 9 and 6, respectively
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9a. Perianth present, showy, differentiated into sepals and petals; petals white
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9b. Perianth, if present, reduced, not differentiated into sepals and petals; petals (or inner tepals), if present, usually green, yellow-green, or brown
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10a. Plants emersed; leaves ± terete in cross-section
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11a. Each carpel with 2 ovules; inflorescence bracteate; each leaf with a terminal pore [Fig. 304]
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11b. Each carpel with 1 ovule; inflorescence without bracts; leaves without terminal pores
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10b. Plants submersed (except often the inflorescence, which is held above the water surface); leaves flat or capillary
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12a. Each flower with 4 tepal-like appendages and 4 stamens; fruits sessile; stipules distinct from the leaves or basally connate with a distinct tip; plants primary of fresh or fresh-tidal waters (in part)
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12b. Each flower with 0 tepals and 2 stamens; fruits long-stipitate; stipules completely connate to the leaves; plants of brackish waters
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7b. Gynoecium composed of 1 carpel or 2 or more connate carpels and then the ovary surmounted by 2 or more stigmas; plants aquatic or terrestrial
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13a. Plants aquatic or marine, with thin, flaccid, often translucent, submersed or floating leaves; flowers unisexual
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14a. Flowers in dense, spherical clusters [Fig. 306], each flower with 1 stigma (in part)
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14b. Flowers not in spherical clusters, each flower with 2–6 or more stigmas
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15a. Flowers with a perianth composed of 3 sepals and 3 petals; androecium usually with 2 or 9 stamens; gynoecium composed of 3–6 weakly united carpels; leaves whorled (at least in part) or all basal (in part)
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15b. Flowers without a perianth; androecium with 1 stamen; gynoecium composed of a single, unilocular, uni- or bicarpellate ovary; leaves alternate or opposite
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16a. Pollen filiform; gynoecium with 2 stigmas; leaves mostly alternate; plants perennial, with rhizomes, marine
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16b. Pollen globose; gynoecium with 2–4 stigmas; leaves opposite; plants annual, without rhizomes, of fresh water habitats (in part)
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13b. Plants of upland or wetland habitats, with firmer leaves that are usually, at least partly, emersed (or at least the leaves holding their form when removed from the water); flowers bisexual, or, less commonly, unisexual
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17a. Inflorescence a spadix
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18a. Leaves ensiform, unifacial, parallel-veined; ovary 2- or 3-locular; anthers introrse; spathe-like bract (actually the distal portion of a sympodial leaf) narrow, grass-like, not concealing the spadix
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18b. Leaves with broad and flat, bifacial, pinnately veined blades; ovary unilocular; anthers extrorse; spathe broad, partially or entirely concealing the spadix (least so in Calla) (in part)
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17b. Inflorescence various, but not a spadix
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19a. Flowers anemophilous or self-pollinated, without a perianth or with an inconspicuous perianth of scales, bristles, or sepaloid tepals
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20a. Flowers arranged in a solitary, terminal, involucrate, white to gray, pseudanthial cluster; roots conspicuously septate
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20b. Flowers arranged otherwise; roots lacking conspicuous septa
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21a. Inflorescence consisting of a dense, elongate, cylindrical spike, the carpellate portion below, the staminate portion above; fruit a wind-dispersed, 1-seeded follicle (in part)
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21b. Inflorescence otherwise; fruit a capsule, achene, utricle, or caryopsis
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22b. Fruit indehiscent; perianth of 2–6 inconspicuous tepals, scales, bristles, or absent altogether
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23a. Ovary with 1 stigma (2 stigmas in Sparganium eurycarpum); perianth of 2–6 tepals; inflorescence a dense, spherical cluster [Fig. 306] (in part)
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23b. Ovary with 2 or 3 stigmas; perianth of scales, bristles, or absent; inflorescence variously open to compact
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19b. Flowers clearly entomophilous, with an evident, showy perianth
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25a. Ovary inferior
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26b. Flowers actinomorphic [Figs. 136,138], with 3 or 6 stamens; pollen separate, not cohering in masses; seeds larger
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27a. Plants vines, dioecious
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27b. Plants upright, not twining, synoecious
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28a. Inflorescence conspicuously white-tomentose; perianth tomentose
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28b. Inflorescence not tomentose; perianth glabrous or minutely pilose
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29a. Flowers with 3 stamens; leaves equitant; seeds without phytomelan
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29b. Flowers with 6 stamens; leaves not equitant; seeds usually with phytomelan
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30a. Perianth pubescent on the abaxial (i.e., outside) surface; leaves pubescent; plants from corms
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30b. Perianth glabrous; leaves glabrous; plants from bulbs
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25b. Ovary superior
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31a. Flowers borne in the axils of firm, imbricate bracts, aggregated in a dense, ellipsoid to ovoid, terminal spike; leaf blades grass-like; petals yellow
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31b. Flowers not from the axils of imbricate bracts, commonly in more open inflorescences; leaf blades various; petal color various
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32a. Sepals sepaloid, green
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33a. Leaf blades grass-like, with parallel venation; inflorescence composed of more than 1 flower; fruit a capsule
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33b. Leaf blades broad, with pinnately branched secondary veins [Fig. 159]; inflorescence composed of a solitary, terminal flower; fruit a berry (in part)
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32b. Sepals petaloid, of a color similar to that of the petals
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34a. Perianth zygomorphic [Fig. 286], the upper lip bearing 1 or 2 closely spaced yellow spots; stamens adnate to the corolla (in part)
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34b. Perianth actinomorphic, lacking yellow spots; stamens free or adnate to the corolla
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35a. Leaves palmately veined (with pinnately branched secondary veins), with a well defined petiole and blade, with stipular tendrils [Fig. 305]
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35b. Leaves parallel-veined, generally lacking a well defined petiole and blade, without tendrils
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36a. Actual leaves scale-like; upper branches filiform, green, simulating leaves, clustered in the leaf axils
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36b. Leaves foliaceous; upper branches not clustered in the leaf axils
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37a. Flowers with 3 stamens; plants aquatic, with flaccid leaves (in part)
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37b. Flowers with 6 stamens (rarely only 4); plants of upland or seasonally saturated soils, with firmer leaves
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38a. Tepals evidently connate; filaments adnate to the tepals or free in Hostaceae
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39a. Tepals 4–18 cm long including the basal, connate portion; anthers versatile
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40a. Leaf blades lanceolate to broad-ovate, 5–200 cm wide; inflorescence a raceme
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40b. Leaf blades linear to lanceolate, 0.8–5 cm wide; inflorescence a solitary flower or an umbel-like helicoid cyme
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41a. Tepals yellow or orange, the basal, connate portion 1.5–3 cm long; plants mostly 5–15 dm tall, from tuberous roots, with flowers borne on an evident scape
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41b. Tepals pink to purple or white (rarely yellow), the basal, connate portion longer than 8 cm; plants shorter than 3 dm, from corms, with short, obscure, subterranean scapes (in part)
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39b. Tepals 0.6–2.2 cm long; anthers basifixed or versatile
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42a. Inflorescence axillary or a secund raceme; fruit a berry (in part)
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42b. Inflorescence a raceme with spirally arranged flowers; fruit a capsule
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43a. Perianth minutely roughened on the abaxial (i.e., outside) surface [Fig. 160]; pedicels ascending; leaf blades 5–26 mm wide
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43b. Perianth not roughened on the abaxial surface; pedicels spreading-ascending to drooping, especially the lower ones [Fig. 128]; leaf blades 2–8 mm wide (10–20 mm wide in Chionodoxa) (in part)
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38b. Tepals distinct or nearly so; filaments free or adnate in Allium, Convallaria, and Streptopus
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44a. Plants with a large rosette of firm leaves that have fibrous margins and a spinose apex; tepals thick and fleshy
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44b. Plants with or without basal rosettes, but the basal leaves (if present) lacking marginal fibers and apical spines; tepals relatively thinner
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45a. Flowers in a many-flowered umbel at the summit of a scape; seeds with phytomelan; plants with the odor of onion or garlic (in part)
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45b. Flowers arranged otherwise (forming an umbel with 3–6 flowers in Clintonia) at the summit of a scape or leafy stem; seeds without phytomelan (except in Ornithogalum) plants without the odor of onion or garlic
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46a. Scape viscid-pubescent; leaves both equitant and distichous
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46b. Stem or scape glabrous or pubescent, but not viscid; leaves not set edge to stem, spirally arranged or, less commonly, distichous
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47a. Leaves in 1 or 2 whorls; styles elongate, capillary, exceeding the tepals in length; fruit a purple to black berry (in part)
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47b. Leaves arranged otherwise; styles shorter; fruit a capsule or berry, the berry blue, red, or becoming red
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48a. Styles 3, separate to the base; fruit a septicidal capsule (loculicidal in Stenanthium)
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49a. Styles simple, unspotted, tepals 2-12 mm long; inflorescence a terminal raceme or panicle (in part)
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49b. Styles distally bifid, maculate; tepals 20–25 mm long; inflorescence of few to several flowers in the axils of leaves (in part)
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48b. Styles 1, divided or lobed only in the apical portion; fruit a berry or loculicidal capsule
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50a. Stems from a bulb or corm; fruit a capsule, circular or bluntly angled in cross-section
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51a. Aerial stems leafy; tepals 30–100 mm long (in part)
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51b. Aerial stems scapose; tepals 12–33 mm long
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52a. Tepals white with an abaxial green stripe or entirely blue; inflorescence a raceme (sometimes a solitary flower in Othocallis); leaf blades not mottled (in part)
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52b. Tepals yellow; inflorescence a solitary flower; leaf blades adaxially mottled (in part)
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50b. Stems from rhizomes; fruit a berry, or a capsule with triquetrous cross-section in Uvularia
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53a. Tepals white; inflorescence terminal, a raceme or panicle [Fig. 302] (in part)
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53b. Tepals yellow, green-white, yellow-green, or pink; inflorescence axillary, an umbel, or a solitary, terminal flower
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54a. Tepals yellow; fruit a capsule; leaves borne on an aerial stem (in part)
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54b. Tepals green-white, pink, or green-yellow; fruit a berry; leaves all basal or borne on an aerial stem (in part)
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Each photo represents one family in this group.