36 XYRIDACEAE. 



1. PELTANDRA Raf. Tufted herbs with rootstocks. Leaf-blades of a 

 hastate or sagittate type. Scapes recurved at maturity. Flowers monoecious, 

 Spadix completely covered with flowers. Stamens 6-10. Spathe green or 

 white. Fruits green or red. 



1. P. virginica (L.) Kunth. Leaf- blades sagittate or hastate, with several 

 prominent lateral ribs: spathes 8-20 em. long, the edges crisped: spadix 

 included, 3^ pistillate, f staminate: fruits mostly over 1 em. thick. — Everglades. 

 — Arrow-arum. 



Order XYRIDALES. 



Terrestrial, commonly bog, herbs, or epij^bytes in Bromeliaceae. 

 Leaves often basal: blades prevailingly narrow. Inflorescence usually not 

 a spadix, but often with a spathe-like bract or a spathe. Flowers mostly 

 complete. Corolla regiilar or nearly so (except in some genera of COM- 

 MELiNACEAE, PoxTEDERiACEAE and Bromeliaceae) . GynoBcium compound, 

 superior or rarely inferior. Fruit a capsule or utricle, or baccate. 



Ovary 1-celled, with parietal placentae : inflorescence without a spathe. 



Fam. 1. Xykidaceae. 

 Ovary 2-3-celled, if incompletely so or if nearly 1-celled 

 then the flowers in a spathe. 

 Flowers minute, monoecious or dioecious, in dense 



heads each seated in an imbricated involucre. Fam. 2. Eriocaulaceae. 



Flowers conspicuous or relatively so, perfect. 



Terrestrial or aquatic plants : foliage not scurfy : 

 stigmas united. 

 Calyx and corolla free, of very different mem- 

 bers : stamens free. Fam. 3. Commelinaceae. 

 Calyx and corolla of quite similar members and 

 partially united : stamens partially adnate 



to the perianth. Fam. 4. roNTEDERiACEAE. 



Epiphytes (our species), with scurfy foliage: 



stigmas 3. Fam. 5. Bromeliaceae. 



Family 1. XYRIDACEAE. Yellow-eyed grass Family. 



Leaves basal : blades thickish. Flowers perfect, in a compact tenninal 

 spike. Sepals 3, the two lateral ones firm, keeled and often appendaged, 

 persistent, the third larger, deciduous. Petals 3, fugacious : anthers 

 linear. Androecium of 3 stamens usually alternating with 3 staminodia. 

 Gynoecium 3-carpellary. Fniit a capsule. 



1. XYRIS [Gronov.] L. Rigid plants with basal equitant leaves and a 

 terminal spike with indurated bracts. — Yellow-eyed grass. 



Lateral sepals included. 



Spikes ovoid, oval or globular ; bracts in several series. 1. X. communis. 



Spikes oblong to conic-oblong; bracts in many series. 2. X. data. 

 Lateral sepals exserted. 



Corolla yellow : upper part of the scape and the spike green. ?,. X. arenicola. 



Corolla white : upper part of the scape and the spike glaucous. 4. A', pallesccns. 



1. X. communis Kunth. Leaves gradually attenuate, shorter than the scapes: 

 scapes 2-7 dm. tall, 2-edged above: spikes oval or globular, 8-1.5 mm. long: 

 bracts closely imbricate in few series: lateral sepals 3-4 mm. long; wing nar- 

 rower than the sepal-body, erose- or incised-toothed above the middle. — 

 Pinelands. — (Cuba, Ant.) 



2. X. elata Chapm. Leaves few, 2-6 dm. long: scapes 3-12 dm. tall, 2-edged 

 above: spikes oblong to conic-oblong, 16-23 mm. long: bracts numerous, 

 closely imbricate in many series: lateral sepals 4-.5 mm. long; wing narrow, 

 toothed above the midille. — Low pinelands. 



