XYRIDACEAE 233 



6. Xyris neg!6cta Small. Perennial, slender. Leaves, few, linear, 3-10 cm. long, 

 acute, straight or slightly curved, rather erect : scapes solitary or commonly 2-4 together, 

 1-4 dm. tall, spirally twisted, 10-ridged, the ridges in pairs, 2 on either side of a line con- 

 necting the 2 more prominent ridges : spikes ovoid, 4-9 mm. long ; bracts 3-5 mm. long : 

 lateral sepals 3-4 mm. long ; wing with erose-serrate crest from near the base to the apex : 

 corolla bright yellow, 3 mm. broad : petals irregularly arose. 



In moist pine lands, Georgia and Florida to Mississippi. Summer and fall. 



7. Xyris Caroliniana Walt. Perennial. Leaves linear, attenuate, smooth, the 

 longer fully as long as the scapes : scapes erect, slender, 1-6 dm. tall, flattened and 2- 

 edged above, the edges smooth : spikes oval or ovoid, 5-9 mm. long, obtuse ; bracts loosely 

 imbricated in few series and splitting in age : lateral sepals 4-5 mm. long ; wing narrower 

 than the sepal-body, incised-toothed or eroded beyond the middle : corolla yellow. 



In swamps and shallow ponds, Vermont to Massachusetts, Florida and Louisiana. Summer. 



8. Xyris communis Kunth. Perennial. Leaves linear, gradually attenuate, shorter 

 than the scapes : scapes solitary or few together, 2-7 dm. tall, 2-edged above : spikes oval 

 or globular, 8-15 mm. long ; bracts closely imbricated in few series : lateral sepals 3-4 

 mm. long, included ; wing narrower than the sepal-body, erose- or incised-toothed above 

 the middle : corolla yellow. 



In bogs and swamps, Maryland to Florida and Louisiana. Summer. Also in tropical America. 



9. Xyris elata Chapm. Perennial. Leaves few, linear, 2-6 dm. long : scapes soli- 

 tary or several together, 3-12 dm. tall, 2-edged above : spikes oblong or conic-oblong, 16- 

 23 mm. long ; bracts numerous, closely imbricated in many series : lateral sepals 4-5 mm. 

 long, included ; wing narrow, toothed above the middle : corolla yellow. 



In swamps near the coast, Maryland to Florida and Louisiana. Summer. 



10. Xyris scabrifblia Harper. Perennial. Leaves few, narrowly and elongated-linear, 

 scabro-puberulent, 3-4 dm. long : scapes surpassing the leaves, and puberulent like them : 

 spikes 1-1.5 cm. long ; bracts rather numerous, closely imbricated : lateral sepals about 5 

 mm. long ; wing narrow, toothed above the middle. 



In bogs, western Georgia. Summer. 



11. Xyris diffdrmis Chapm. Perennial. Leaves few, linear, 1-5 dm. long, smooth : 

 scapes 2-5 dm. tall, mostly clustered, twisted, sharply 2-edged above, smooth : spikes ovoid, 

 12-18 mm. long, acute, the bracts rounded : lateral sepals 4.5-6 mm. long ; wing narrow 

 or obsolete near the base of the sepal, with a crest of fringe extending J J the length of the 

 sepal from the tip : corolla yellow. 



In swamps, Florida, Georgia and Alabama. Spring and summer. 



12. Xyris serdtina Chapm. Similar to X. di/ormis in habit. Leaves and scape 

 rough-margined : spikes ovoid, 12-18 mm. long, obtuse ; bracts rounded : lateral sepals 

 4.5-5 mm. long ; wing broad to the base of the sepal, with a fringed crest mainly above 

 the middle : corolla yellow. 



In pine-land swamps, western Florida. Summer and fall. 



13. Xyris platylepis Chapm. Perennial. Leaves linear, 2-6 dm. long : scapes erect, 

 solitary or sometimes few together, 5-9 dm. tall, 2-ridged above, sometimes slightly rough- 

 ened on the margins : spikes oblong or cylindric, 1.5-3 cm. long ; bracts very broad and 

 broadly truncate or nearly so at the apex : lateral sepals 4.5-6 mm. long ; wing with a 

 lacerate, crest above the middle : corolla yellow. 



In low or swampy pine lands, South Carolina to Florida and Louisiana. Summer and fall. 



14. Xyris iridifolia Chapm. Perennial. Leaves linear, 5-8 dm. long, relatively 

 broad : scapes 6-10 dm. tall, stout, nearly terete or 1-edged below, flattened and 2-edged 

 above, the edges broad : spikes oblong or cylindric, 1.5-3.5 cm. long ; bracts rounded : 

 lateral sepals 5-6 mm. long ; wing narrow, incised-fimbriate its whole length ; corolla 

 yellow. 



In shallow ponds, Georgia and Florida to Texas. Summer and fall. 



15. Xyris Ellidttii Chapm. Perennial, lustrous. Leaves numerous, narrowly linear, 

 grass-like, 3-10 cm. long or longer, acute, often twisted : scapes solitary or clustered, 2-5 

 dm. tall, twisted, 2-edged throughout, or only 1-edged below, roughish on the edges ; 

 spikes oval or ellipsoidal ; bracts with thin eroded edges : lateral sepals 4-6.5 mm. long, 

 exserted ; wing incised-lacerate above the middle or nearly entire below the terminal tuft or 

 beard : corolla yellow. 



In damp pine lands, South Carolina to Florida and Alabama. Summer. 



16. Xyris Smalliana Nash. Perennial, lustrous. Leaves linear, 3.5-7 dm. long, 

 the lower half often purplish, striate : scapes 7-10 dm. tall, about twice as tall as the 

 leaves, flattened, unequally 2-edged below the spikes, smooth : spikes ovoid or at maturity 



