The Flowering Plants: Flowering Rush to Rushes

Key to the Families of Monocotyledons in Illinois

Key to the FAMILIES of Monocotyledons in Illinois ~ THOSE ENTRIES MARKED WITH AN ASTERISK WILL BE FOUND IN SUBSEQUENT VOLUMF1>. 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_______ _ _______________________:...________________Smilacaoeae 0. 2. Inflorescence glomerulate or paniculate; ovary inferior; fruit a capsule_______________________________Dioscorcaceae 0. 1. Plants erect or floating in water (tendrils never present); leaves mostly parallel-veined; flowers bisexual or unisexual. 3. Plants with one or two whorls of leaves. 4. Flowers radially symmetrical; ovary supel'ior; stamens 6. 5. Plants never over 50 em tall; flowers usually borne singly ________________Tl·illium and Medeola, in Liliaceae 0. 5. Plants more than 50 em tall; flowers usually more than one _____________________________Lilium, in Liliaoeae 0. 4. Flowers bilaterally symmetrical; ovary inferior; stamen L __ _ _____________________________Isotria, in Orchidaoeae " 3. Plants with leaves alternate, opposite, basal, or none, or in several whorls. 6. Flowers crowded together on a spadix, often subtended by a spathe_______________________________Araceae, p. 124 6. Flowers not crowded on a spadix ( in Ruppia, two flowers are borne on a spadix-like structure). 7. Plimts thalloid, floating in watec____Lemnaoeae•.p. 138 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. 10. Leaves 2"ranked; sheaths usually open; stems usually hollow, with solid nodes, often terete; anthers attached above the base____lPoaceae ,I Key to Families I 19 10. Leaves 3-l'anked (when present) ; sheaths closed; stems solid, with soft nodes, often 3angled ; anthers attached at the base_________ ___________________________ Cyperaceae (> g. Flowers not subtended by individual scales; plants mostly aquatics. 11. Plants erect; inflorescence terminal, spicnte, thick; leaves very long, linear, strap-shaped__ _ _______________________Typhaceae, p. 163 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 dl'ying____________________ _ ___________Potamogetonaceae, p. 67 13. Stamens 2; flowers on a short spadix, concealed within the leaf sheath; fruit stipitate, drupe-like_______________ ________________Ruppiaceae, p. 109 12. Leaves opposite; stamen 1; inflorescence not spicate, axillary. 14. Carpel one; fruit beaklesL__________ ________________Najadaceae, p. 115 14. Carpels 2-4; fruit beaked_________ _ _____ _______Zannichelliaceae, p. 111 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 textul'e) . 17. Inflorescence umbellate; pistils 6, coherent at base; fruit a follicle____________ _ ___________________Butomaceae, p. 22 17. Inflorescence not umbellate; pistils 10 or more, free to base; fruit an achene_____ _ 20 / RUSH TO RUSHES ____________________Alismaceae, p. z3 ,.6. Calyx and corolla undifferentiated {i.e., similar in color and texture) __________________ _____________________Juncaginaceae,p.61 15. Pistil one, compound. 18. Ovary superior. 19. Calyx and corolla differentiated (in color and textnre). zoo Flowers crowded together in a dense head; leaves basaLXyridaceae, p. 168 120. Flowers borne in cymes or umbels; leaves cauline___________________ ___________Commelinaceae, p. 172 19. Calyx and corolla undifferentiated (i.e., similar in color and texture). Z1. Flowers unisexual. 22. Leaves net-veined; flowers in umbeIL____________Smilacaceae 0 22. Leaves parallel-veined; flowers in globose clusters, racemes, or panicles . 23. Perianth small, greenish; flowers aggregated in dense globose clusters; stamens 5---______Sparganiaeeae , p. 155 23. Perianth usually conspicuous, greenish, yellowish, white, 01' bronze-purple; flowers in racemes or panicles; stamens 6 _______________Liliaceae .. 21. Flowers bisexual. 24. Perianth scariouL____________ _____________Juncaceae,p.194 24. Perianth petaloid. 25· Stamens 3--------------_____Pontederiaceae , p. 187 25. Stamens 6 (or 4). 126. Stamens of different sizes _______________ _ __Pontederiaceae, p. 187 126. Stamens all alike. 27. Leaves evergreen, 18. Ovary inferior. Key to Families I Z1 rigid; stems woody__ Yucca, in Liliaceae '" 27. Leaves deciduous, mostly not rigid; stems hel'baceouL_ ________Liliaceae '" 28. Plants growing in water. 29. Leaves whorled________________ _ ___________Hydrocharitaceae, p. 52 29. Leaves basal, or cauline and alternate. 30. Stamens 2, or 6-12, never 3; flowers unisexual; styles not peta10id____Hydl 'ocharitaceae, p. 52 30. Stamens...