GRAMINE^ (grass FAMILY.) 609 



54. DIPLACHNE, Beauv. 



Spikelets rather loosely flowered. Flowering glumes 2-toothed, mucronate 

 or awned between the teeth. Otherwise like the preceding. — Margins of the 

 flowering glumes fringed (except the last). 



1. D. dubia, Benth. Culms 2° high, slender; leaves elongated, filiform, 

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

 the filiform rachis, 6-flowered ; glumes lanceolate, nearly equal, serrulate on 

 the keel, shorter than the awnless soon spreading florets ; flowering glumes 

 truncate or emarginate. — South Florida. 



2. D. faseieularis, Beauv. Culms h°-4° long, mostly prostrate and 

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

 sheaths of the elongated leaves; spikes numerous, approximate, erect, 3' -5' 

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

 florets ; flowering glumes prominently awned. — Brackish swamps along the 

 coast. Sept. (l). 



3. D. Domingensis, (Link.?) Culms erect, simple, straight and slen- 

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

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

 rough-keeled ; flowering glumes minutely awned. — South Florida. Oct. — 

 Culms l''-H° high. 



4. D. rigida, Muuro. Culms low (2'- 4' high), ascending, rigid; leaves 

 subulate, ^ - 1|' long, involute and rigid ; spike 1'- 1|' long, lanceolate, dense, 

 1-sided; spikelets linear, acute, 5-11-flowered; glumes serrulate on the keel; 

 flowering glume obtuse, emarginate or mucronate, glabrous. (Foa rigida, L.) 

 — Waste ground, introduced in ballast. April -May. 



55. TRIODIA, R. Br. 



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

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

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

 ginate, shorter than the crowded florets. Flowering glumes 2-cleft, shortly 

 3-awned by the percurrent hairy nerves, bearded at the base. Stamens 3. 

 Grain obovate-oblong, free. 



1. T. cuprea, Jacq. Panicle ample and diffuse, or contracted and erect, 

 bearded in the axils; spikelets terete, lanceolate, mostly purple; flowering 

 glume with two awn-like teeth similar to the three short awns. — Woods and 

 margins of fields. August - Sept. — Culms 3°- 5° high. Sheaths often hairy. 



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

 axils, clammv; spikes ovate or roundish, compressed; teeth of the flowering 

 glume obtuse, wider than the three short awns. — Low pine barrens, Florida 

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



3. T. eragrostoides, V. & S. Panicle large, diffuse, the branches 

 single and drooping; spikelets oblong, compressed, 6 -10-flowered ; flowering 

 plumes truncate and finely denticulate, slightly awned ; culms tall and slen- 

 der; leaves r'-2" wide. —Florida, and westward. 



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