294 



IXIACEAE 



Spathes 2 together, or rarely 3. 



Plants smooth (rarely with the bracts obscurely roughened 



in nos. 6 and 8) : leaf-blades mostly 1.5-3 mm. wide. 

 Plants drying green : capsules pale, 2-3 mm. high. 

 Plants drying dark : capsules dark, 4-6 mm. high. 

 Plants more or less scabrous (sometimes smooth in no. 8), not 



drying dark : leaf-blades mostly 1-2 mm. wide. 

 Spathes mostly green: outer bract of the second spathe 



slender- prolonged : perianth pale blue. 

 Spathes mostly red-purple : outer bract of the second spathe 



as long as the inner : perianth deep violet-blue. 

 ** Spathe subtended by an accessory outer slender bract : tufts of 



plants densely fibrillose at the base, 

 b. Tufts of plants with both simple and branched scapes, the latter being 



terminated by 1 or 2 peduncles. 

 Scapes wiry, nearly terete : spathes green, mostly narrow and almost 



terete at the base. 



Scapes flattened, distinctly winged : spathes mostly purplish, flattened. 

 Plants drying dark : leaf-blades rather thin : bracts of the spathe 



smooth. 



Plants not drying dark : leaf-blades rather stiff : bracts rough. 

 B. Scapes branched or bearing 2 or more terminal peduncles. 

 Tufts of plants densely fibrous at the base. 



Plants drying very dark. 

 Leaves and scap 



scapes smooth. 

 Bracteal leaf conspicuously elongated ; leaf-blades 2-4 mm. 



wide, finely cross-rugulose. 

 Bracteal leaf short and narrow : leaf-blades 1-2 mm. wide, not 



rugulose. 

 Leaves and scapes more or less roughened on the sides : interior 



scales much shorter than the bracts of the spathe. 

 Plants pale and glaucous, or not very dark when dry. 



Scapes slender, often flexuous, ciliolate-serrulate : plants rather 



bright or deep green : peduncles very short or subfascicled. 

 Scapes rather stiff or stout : plants pale or glaucous : peduncles slen- 

 der, not fascicled. 

 Scapes flattened and wing-margined or broadly winged. 



Leaf-blades and scapes mostly manifestly serrulate : peduncles 



usually 5-10 cm. long : staminal column 4-5 mm. high. 

 Leaf-blades and scapes mostly smooth-edged : peduncles 2-5 



cm. long : staminal column 2-4 mm. high. 

 Scapes subterete or narrowly margined. 



Leaves numerous ; blades elongated, becoming flexuous, 2-4 



mm. wide : plants flowering from February to March. 

 Leaves few; blades more slender and much narrower and 



shorter : plants smaller, flowering from June to August. 

 Tufts of plants without fibers, or not densely fibrous at the base. 



a. Plants more or less stiffly erect or erect-ascending ; scapes not usually 

 branched below the middle : peduncles usually shorter than the 

 scape proper: species, except S. graminoides, not occurring west 

 of the Mississippi River, as far as known. 

 Plants drying very dark (except no. 26). 



Scapes and leaf-blades mostly 2-4 mm. wide or more : pedicels 



finally much spreading or recurved. 

 Inflorescence not repeatedly dichotomous. 



Capsule thick- walled : bracts of the spathe closely striate- 



nerved, 2-2.5 cm. long. 

 Capsule thin-walled : bracts of the spathe not closely stri- 



ate-nerved, the inner one 2 cm. long or less. 

 Perianth about 10 mm. long or more. 



Capsules 2.5-4 mm. high, on recurved pedicels : seeds 



few in each cavity. 

 Capsules 3-6 mm. high, on spreading pedicels. 



Interior scales much shorter than the bracts of the 



spathe : seeds numerous. 

 Interior scales often equalling the bracts of the 



spathe : seeds 2-3 in each cavity. 

 Perianth 5-8 mm. long : capsules 1.5-3 mm. long : seeds 



2-3 in each cavity. 

 Inflorescence more or less dichotomous from successive nodes : 



perianth about 5 mm. long, white or perhaps also blue. 

 Scapes and leaf-blades mostly 1-2 mm. wide : pedicels erect or 



nearly so. 

 Leaves and scapes mostly smooth-edged, the scapes becoming 



widely flexuous : peduncles very slender, 5-12 cm. long. 

 Leaves and scapes serrulate, erect : peduncles 3-7 cm. long. 

 Plants pale or bright green, not drying very dark. 



Roots thickened and clustered, becoming 1.5 mm. thick or more : 



Florida species, the plants becoming 50-80 cm. tall. 

 Leaves very long, equalling the tufts ; blades 1.5-2.5 mm. wide : 



capsules thin-walled, subglobose, 5-6 mm. high. 

 Leaves shorter than the scapes; blades becoming 3-4 mm. 

 wide: capsules thick- walled, broadly oblong, 2.5-5 mm. 

 high. 



Roots less clustered, not thickened, usually slender and fibrous : 

 plants mostly 15-50 cm. tall. 



6. S. albidum. 

 5. S. sagittiferum. 



7. S. scabrellum. 



8. S. Asteanum. 



9. S. capillarc. 



10. S. btforme. 



11. S. intermedium. 



12. S. versicol&r. 



13. S. xerophyUum. 



14. S.fuscatum. 



15. S. incruptatum. 



16. S. ruflpes. 



17. S.fibromm. 



18. S. tortum. 



19. S. Floridanum. 



20. S. Nashii. 



21. S. soMitialc. 



22. S. recitrratum. 



23. S. graminoides. 



24. S. membranaccum. 



25. S. tenellum. 



26. S. dichotomum. 



27. S.flagcttum. 



28. S. Miamiensc. 



29. S. longifolium. 



30. -S. corymbosum. 



