30 TRIANDRTA. MONOGTNIA. 



axillary or terminal; (growing chiefly in arid and saline 

 wastes ) 



Species. 1. *Jmericamtmj;. There are of this genus 5 

 other species, 4 in Siberia, the 5th near the Caspian sea. 



45, XYRIS. L, (Yellow Floweriiig-Rusli.) 



Flowers in an ovate-cylindric capitulum. — 

 Calix glumaceous, 3 valved, valves unequal, 

 the outer coriaceous. Corolla 3-petalled, equal. 

 iS'%?wa trifid. Ca^^szt/e 1 -celled, 3-valved. Seeds 

 very numerous, and minute. 



Leaves all radical, gramineous, or like those of the Iris, 

 linear, or ensiform-subulate, sometimes tortuose, intimate- 

 ly slieaihing at their base; the vaginx of the leaves ofien 

 enveloped in a gelatinous fluid. Scapes simple, round,^ 

 ancipital, or contorted, terminating in a dense spike or ca- 

 pitulum. Flowers closely imbricated; of very short du- 

 ration, generally yellow, (in the X. americana of Guianne, 

 blue, but the leaves triquetrous, and the outer glumes 

 . acute!) Petals retuse, often crenate. Outer glumes of the 



capitulum concave, rounded, and obtuse, frequently abor- 

 tive below. 



Species. l.Indica. 2. CaroUniana. (X Juplcai. Mich. 

 X.Jfexuosaof Muhlenberg's Catalogue.) 3. Jimbriata, El- 

 liott. 4- brevifoUa. S.juncea. 



Obs. Of this genus there are 2 species in India, 1 at 

 the Cape of Good Hope, 1 in Peru, and another in Gui- 

 .anne (South America,) the rest in the United States, of 

 which the X. Indica is common to India and North Ajiie- 

 rica as far as the 40th degree of north latitude. 



f ttt Flowers ghimaceous. 



44. KYLLINGIA. Z. 



Flowers distinct, disposed in a roundish, ses- 

 sile, subimbricated spike, or umbellate, the 



f Perennial; stem cespitose, leaves opposite, connate, crowd- 

 ed, subulate, triquetrous, rather pungent; flowers triandrous? 

 terminal. 



On the arid hills of the Missouri. 



Obs. This species greatly resembles the P. arveJise of Eu. 

 rope, but is distinctly perennial; I have not, however, had the 

 opportunity of examining good specimens, seeing it only in 

 fruit. 



