VOL. I. GENERAL KEY TO THE ORDERS AND FAMILIES. xxiii 



Carpels distinct. Order 3. ALISMALES. 



Petals similar to the sepals; anthers mostly elongated. Fam. 6. Scheuchzeriaceae. i : 91. 



Petals not similar to the sepals; anthers short. Fam. 7. Alismaceae. i : 93. 



Carpels united. Order 4. HYDROCHARITALES. 



Ovary i-celled with parietal placentae. Fam. 8. Vallisneriaceae. 1:104. 



Ovary 6-9-celled. Fam. 9. Hydrocharitaceae. i: 106. 

 tt Flowers in the axils of dry chaffy scales (glumes), arranged in spikes or spikelets. 



Orders. GRAMINALES (Glumiflorae) . 



Fruit a caryopsis (grain) ; stems (culms) mostly hollow in our species. Fam. 10. Gramineae. i : 107. 

 Fruit an achene ; stems (culms) solid. Fam. 11. Cyperaceae. 1:295. 



(Order 6, PALMALES, including only the family Palmaceae, Palms, and Order 7, CYCLANTHALES, 

 including only the family Cyclanthaceae, are not represented in our territory.) 



** Inflorescence a fleshy spadix, with or without a spathe; or plants minute, floating free, the flowers few or 



solitary on the margin or back of the thallus. 



OrderS. ARALES (Spathi florae). 



Large herbs, with normal foliage and well-developed spadix. Fam. 12. Araceae. i : 441. 



Minute floating thalloid plants. Fam. 13. Lemnaceae. 1:446. 



2. Carpels united into a compound ovary; parts of the usually complete flowers mostly in s's or 6's. 



* Seeds with endosperm. 



t Flowers regular, or nearly so (corolla irregular in Coinineliiia and Pontederia). 



J Endosperm mealy ; ovary superior. 



Order 9. XYRIDALES (Farinosae). 

 a. Ovary i -celled. 



Aquatic moss-like leafy herbs; flowers solitary. Fam. 14. Mayacaceae. i : 450. 



Erect rush-like herbs; flowers in terminal scaly heads or spikes. Fam. 15. Xyridaceae. i : 450. 



Mud or aquatic herbs, the flowers subtended by spathes (Heteranthera in Pontederiaceae i: 462). 



b. Ovary 2-3-celled (except in some Pontederiaceae). 



Flowers very small, densely capitate, monoecious or dioecious. Fam. 16. Eriocaulaceae. i : 453. 



Flowers perfect. 



Epiphytes ; leaves scurfy. Fam. 17. Bromeliaceae. 1:456. 



Terrestrial or aquatic herbs ; leaves not scurfy. 



Perianth of 2 series of parts, the outer (sepals) green, the inner (petals) colored. 



Fam. 1 8. Commelinaceae. i : 457. 

 Perianth 6-parted. Fam. 19. Pontederiaceae. 1:462. 



it Endosperm fleshy or horny; ovary superior or inferior. 



Order 10. LILIALES. 



a. Ovary superior (except in Aletris, in the Liliaceae, and some species of Zygadenus in the 



Melanthaceae). 



Perianth-segments distinct, green or brown, not petal-like ; herbs with grass-like leaves and small 

 flowers. Fam. 20. Juncaceae. i : 465. 



Perianth-segments distinct, or partly united, at least the inner petal-like. 



Fruit a capsule (except in Yucca baccata, where it is large, fleshy and indehiscent). 



Capsule mostly septicidal ; plants rarely bulbous. Fam. 21. Melanthaceae. 1:485. 



Capsule loculicidal (septicidal in Calochortus) ; plants mostly bulbous. 



Fam. 2. Liliaceae. i : 495. 



Fruit a fleshy berry (except in Uvularia of the Convallariaceae). 

 Erect herbs ; tendrils none ; flowers perfect. 



Leaves basal or alternate. Fam. 23. Convallariaceae. i : 513. 



Leaves verticillate. Fam. 24. Trilliaceae. I : 522. 



Vines, climbing by tendrils, or rarely erect ; flowers dioecious, in axillary umbels. 



Fam. 25. Smilaceae. i : 526. 



b. Ovary inferior, wholly or in part. 



Stamens 3, opposite the inner corolla-segments. Fam. 26. Haemodoraceae. i : 530. 



Stamens 6 in our species. 



Erect perennial herbs; flowers perfect. Fam. 27. Amaryllidaceae . i : 531. 



Twining vines; flowers dioecious. Fam. 28. Dioscoraceae. i : 535. 



Stamens 3, opposite the outer corolla-segments. Fam. 29. Iridaceae. i : 536. 



tt Flowers very irregular; ovary inferior. 



Order 1 1. SCITAMINALES. 



One family represented in our territory. Fam. 30. Marantaceae. i : 546. 



** Seeds without endosperm, very numerous and minute ; ovary inferior. 



Order. 12. ORCHIDALES (Microspermae). 



Flowers regular; stem-leaves reduced to scales. Fam. 31. Burmanniaceae. i : 546. 



Flowers very irregular. Fam. 32. Orchidaceae. i : 547. 



Subclass 2. DICOTYLEDONES. i : 577. 



EMBRYO NORMALLY WITH 2 COTYLEDONES ; STEMS MOSTLY DIFFERENTIATED INTO PITH, WOOD AND BARK; 



LEAVES MOSTLY NET-VEINED. 

 Series i. CHORIPETALAE. i : 577 to 2 : 666. 



Petals distinct to the base, or wanting (exceptions noted Vol. i : 577). 



A. Petals none, except in Portulacaceae and in most Caryophyllaceae, which are herbs with leaves 

 nearly always opposite, the seeds with endosperm, and in the pistillate flowers of the walnuts 

 (J-uglans). 



i. Calyx none (except in the Juglandaceae, which are trees with odd-pinnate leaves). 

 Marsh herbs with perfect flowers in nodding spikes. Order i. PIPERALES. 



