MONOCOTYLEDONOUS OR ENDOGENOUS PLANTS. 567 



149. YELLOW-EYED GRASS FAMILY. Order, 

 Xyridace.'E. 



Perennial stemless marsh herhs, with fibrous roots, sword- 

 shaped equitiint haves, and perfect irregular fugacious 

 flowers, collected in a dense imbricate-bracted spike ; sejmls 

 3 ; the two lateral ones glnmaceous, keeled, persistent, the 

 inner one hyaline, infolding, in the bud, the petals and 

 caducous stamens ; ^;e/rt/5 3, rounded, distinct, or united 

 by their long claws; stamens 3, and inserted on the sum- 

 mit of the claws of the petals, or G, and the alternate ones 

 sterile, hypogynous, and commonly bearded with jointed 

 hairs; anthers erect, 2-celled, extrorse; ovary free, 1-3- 

 celled ; style single, 3-parted ; capsule 3-valved, many- 

 seeded ; seeds minute, orthotropous ; embryo minute, at 

 the apex of the albumen. Sca2)e commonly twisted or 

 spiral, 2-edged near the summit, with a spathe-like sheath 

 at the base; spikes mostly solitary. 



XYRIS, L. Yellow-eted Grass. 



Pe^fl?5 distinct; stamens 6, the alternate ones hypogy- 

 nous, sterile, commonly bearded at the summit, and 

 slightly cohering with the claws of the contiguous petals; 

 stigmas entire; capsule 1-celled, 3-valved, the valves bear- 

 ing the placentae in the middle ; seeds very numerous, 

 finely ribbed ; spikes ovoid or oblong ; bracts coriaceous or 

 somewhat crustaceous, rounded, closely imbricated, convex 

 and discolored on the back, the lower ones empty; keel of 

 the lateral sepals mostly winged and variously lacerated ; 

 flowers yellow. 



Sheath of the scape longer than the leaves. Biennials ? 



X. brevifolia, Michx. Scape nearly terete, smooth ; 

 leaves narrowly linear, smooth on the edges ; spike globose, 

 light brown, few-flowered ; bracts soon lacerated at the 



