GRAMINE^. ((;RASS FAMILY.) 559 



2. L. dubia., Nccs. Culms 2° higli, sloiulcr ; loaves clonp;atc<l, filiform, 

 with smooth sheaths; spikes 6-10, somowluU corymbose; spikelets distant on 

 the tilifonn raehis, 6-llo\vcrcd ; glumes lanceolate, nearly equal, serrulate on the 

 keel, shorter than the awiiless soon spreading flowers ; jialcae fringed on the mar- 

 gins, the lower one truncate or emarginate. — South Florida. 



§ 2. DIPLACHNE. — Lotcer paka 2-chfl, 1 - 3-a;r«eJ. 



3. L. polystachya, Kunth. Culms h° - 4° long, mostly prostrate and 

 rooting at the lower joints, much branched ; raceme partly included in the 

 sheaths of the elongated leaves; si)ikes numerous, approximate, erect, 3' -5' 

 long; spikelets lanceolate, 8- 10-flowered ; glumes unequal, shorter than the 

 flowers ; lower palca hairy on the margins below, 3-a\vned ; the lateral awns 

 minute, the middle one about as long as the palea. (Festuca polystachya, 

 Michx.) — Brackish swamps along the coast, Florida, and northward. Sept (1) 



4. Ij. Domingensis, Link.? Culms erect, simple, straight and slender; 

 leaves narrowly linear or filiform, shorter than the culm ; spikes 6- 12, scattered, 

 exserted; spikelets lanceolate, 6-8-flowered; glumes unequal, acute, rough- 

 keeled ; lower palea hairy on the margins, much longer than the single rough 

 awn. — South Florida. Oct. — Culms 1° - U° high. 



24. TRIOUSPIS, Bcauv. 



Perennial grasses, with tall, erect, simple culms, from a thick and scaly root- 

 stock, elongated rigid leaves, and ovate or lanceolate 5 - 7-flowered stalked spike- 

 lets, disposed in a simple or compound open panicle. Glumes 2, smooth, emar- 

 ginate, shorter than the crowded flowers. Paleaj 2, 2-cleft, the lower one shortly 

 3-awned by the pei-current hairy nerves, bearded at the base. Stamens 3. Grain 

 obovate-oblong, free. 



1. T. sesslerioides, Toit. Panicle ample and diffuse, or contracted and 

 erect, bearded in the axils ; spikelets terete, lanceolate, mostly purple ; lower 

 palea with two awn-like teeth similar to the three short awns. (Poaquinquitida, 

 Pursh.) — Dry .soil, Florida, and northward. Aug. and Sept. — Culms 3°-5*' 

 high. Sheaths often hairy. 



2. T. ambigua. Panicle short, nearly simple, spreading, smooth in the 

 axils, clammy ; spikes ovate or roundish, compressed ; teeth of the lower palea 

 obtuse, wider than the three short awns. (Poa ambigua, E/l.) — Low pine bar- 

 rens, Florida to South Carolina. August. — Culms 2° -3° high. 



25. TRIPLASIS, Beauv. 



Low tufted fibrous-rooted grasses, with branching culms, linear-subulate leaves, 

 and few 4-flowered purple spikelets, disposed m reduced lateral and terminal 

 panicles. Flowers scattered on the slender raehis. Glumes 2, lanceolate, smooth. 

 PaleiE 2, hairy on the margins ; the lower one 2-cleft, with a bearded or plumose 

 awn between the teeth ; the u])per concave, 3-toothed. Stamens 3. Grain free. 



1. T. Americana, Beauv. Culmscrect, l°-l^°high; lo.ivesandsheaths 

 hairy; lateral panicles included ; awn of the lower palea jjlumosc;, much longer 



