Flowering Plants: Lilies to Orchids

Key to Families of Monocotyledons in Illinois

Key to the Families of Monocotyledons m Illinois ;:, THOSE ENTRIES MARKED WITH AN ASTERISK APPEARED IN THE VOLUME OF FLOWERING PLANTS COVERING FLOWERING RUSH TO RUSHES. ;:, ;:, THOSE ENTRIES MARKED WITH A DOUBLE ASTERISK WILL BE FOUND IN SUBSEQUENT VOLUMES. 1. Plants climbing or twining (if erect, then usually with a few weak tendrils from the upper axils); leaves net-veined; flowers unisexual. 2. Inflorescence umbellate; ovary superior; fruit a berry_______ _ ___ _______ _____ ____ _____ ________ ___Smilacaceae, p. 128 2. Inflorescence glomerulate or paniculate; ovary inferior; fruit a capsule___________________________Dioscoreaceae, p. 146 1. Plants erect or floating in water (tendrils never present) ; leaves mostly parallel-veined; flowers bisexual or unisexual. 6 3· Plants with one or two whorls of leaves. 4· Flowers radially symmetrical; ovary superior; stamens 6. 5· Plants never over 50 em tall; flowers usually borne singly _____________Trillium and Medeola, in Liliaceae, p. 99 5· Plants more than 50 em tall; flowers usually more than one______________________Lilium, in Liliaceae, p. 27 4· Flowers bilaterally symmetrical; ovary inferior; stamen 1_ __ _ ________________________Isotria, in Orchidaceae, p. 244 3· Plants with leaves alternate, opposite, basal, or none. 6. Flowers crowded together on a spadix, often subtended by a spathe ___________________________________Araceae" 6. Flowers not crowded on a spadix (in Ruppia, two flowers are borne on a spadix-like structure.) 7· Plants thalloid, floating in water__________Lemnaceae" 7· Plants with roots, stems, and leaves, aquatic or terrestrial. 8. Perianth absent, or reduced to very minute scales (lodicules ) or bristles. g. Each flower subtended by one or more sterile scales; plants generally not true aquatics. Key to Families I 7 10. Leaves 2-ranked; sheaths usually open; stems usually hollow, with solid nodes, often terete; anthers attached above the base___Poaceae"" 10. Leaves 3-ranked (when present); sheaths closed; stems solid, with soft nodes, often 3-angled ; anthers attached at the base__________ _ -------------------------- Cyperaceae '"' g. Flowers not subtended by individual scales; plants mostly aquatics. 11. Plants erect; inflorescence terminal, spicate, thick; leaves very long, linear, strap-shaped__ _ ____________________________Typhaceae 0 11. Plants not erect, free-floating or sometimes rooted in bottom mud; inflorescence axillary or terminal and slenderly spicate; leaves not as above. 12. Leaves alternate; stamens 2 or 4; inflorescence spicate and usually terminal, or with flowers borne 2 per spadix. 13. Stamens 4; flowers in a spike or head; fruit sessile, appearing as an achene upon drying _______________Potamogetonaceae 0 13. Stamens 2; flowers on a short spadix, concealed within the leaf sheath; fruit stipitate , drupe-like___________Ruppiaceae " 12. Leaves opposite; stamen 1; inflorescence not spicate, axillary. 14. Carpel one; fruit beakless___Najadaceae 0 14. Carpels 2-4; fruit beaked_____________ _ ------------------- Zannichelliaceae 0 8. Perianth present, composed of either calyx or corolla or both (plants with the perianth reduced to minute scales or bristles should be sought under the first 8) . 15. Pistils simple, more than one, separate or slightly coherent at base. 16. Calyx and corolla differentiated (in color and texture). 17. Inflorescence umbellate; pistils 6, coherent at base; fruit a follicle _________Butomaceae 0 17. Inflorescence not umbellate; pistils 10 or more, free to base; fruit an achene________ _ -------------------------- Alismaceae 0 8 I LILIES TO ORCHIDS 16. Calyx and corolla undifferentiated (i.e., similar in color and texture) _________Juncaginaceae" 15. Pistil one, compound. 18. Ovary superior. 19. Calyx and corolla differentiated (in color and texture). 20. Flowers crowded together in a dense head; leaves basal_ ______________Xyridaceae" 20. Flowers borne in cymes or umbels; leaves cauline_______________Commelinaceae " 19. Calyx and corolla undifferentiated (i.e., similar in color and texture) . 21. Flowers unisexual. 22. Leaves net-veined; flowers in umbels__ _ ________________Smilacaceae, p. 128 22. Leaves parallel-veined; flowers in globose clusters, racemes, or panicles. 23. Perianth small, greenish; flowers aggregated in dense globose clusters; stamens 5------------Sparganiaceae" 23. Perianth usually conspicuous, greenish, yellowish, white, or bronze-purple; flowers in racemes or panicles; stamens 6_________________Liliaceae, p. 11 21. Flowers bisexual. 24. Perianth scarious_________Juncaceae" 24. Perianth petaloid. 25. Stamens 3---------Pontederiaceae" 25. Stamens 6 (or 4). 26. Stamens of different sizes________ -------------- Pontederiaceae" 26. Stamens all alike. 27. Leaves evergreen, rigid; stems woody___Yucca, in Liliaceae, p. 115 27. Leaves deciduous, mostly not rigid; stems herbaceous_______ _ ______________Liliaceae, p. 11 18. Ovary inferior. 28. Plants growing in water. zg. Leaves whorled______Hydrocharitaceae" 29. Leaves basal, or cauline and alternate. Key to Families I 9 30. Stamens 2, or 6-12, never 3; flowers unisexual ; styles not petaloid___________ _ _________________Hydrocharitaceae ':1 30. Stamens 3; flowers bisexual; styles petaloid________________lridaceae , p. 150 28. Plants...