XYRIDACEAE 233 



6. Xyris negl^cta 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 Carolini^na Walt. Perennial. Leaves linear, attenuate, smooth, the 

 longer fully I as long us 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 difformis 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 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. diffonnis 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-fimbriafe 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 Smallikna 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 



