612 GRAMINE.E. (GRASS FAMILY.) 



the margins, 7 - 9-nerved. Florets similar, the glume scarious at the apex. 

 Stamens 3. Grain free. Culms simple. Root perennial. 



1. M. mutica, Walt. Culms slender, l-2high; leaves and sheaths 

 pubescent or glabrous ; panicle composed of few simple few-flowered branches, 

 or reduced to a simple raceme ; spikelets racemose, nodding, 2-flowered ; 

 glumes nearly equalling the spikelet, obtuse or acute ; sterile flowers obovate. 

 Rich open woods. April -May. 



2. M. diffusa, Pursh. Culms 2 - 4 high ; panicle compound, many- 

 flowered ; spikelets mostly 3-flowered ; glumes shorter than the spikelet ; 

 flowering glume acute. Carolina (Pursh). 



60. GLYCERIA, Brown. 



Smooth perennial marsh or aquatic grasses, with flat leaves and few- or 

 many-flowered spikelets disposed in a simple or compound panicle. Rachis 

 jointed. Glumes membranaceous, obtuse, persistent. Florets somewhat char- 

 taceous, early falling away with the separating joints of the rachis ; the glume 

 naked, convex, 5- 7-nerved. Stamens 2-3. Grain free, oblong. 



* Panicle contracted. 

 t- Spikelets terete, 5- 13-jlowered : flowering glume scabrous. 



1. G. fluitans, R. Brown. Culms thick, ascending from a creeping 

 base, 1- 5 long ; leaves long, broadly linear ; panicle long and narrow ; spike- 

 lets linear, pale, loosely 7 - 13-flowered (!' long) ; flowering glume obtuse, or 

 slightly 3-lobed at the scarious apex, roughish, 7-nerved. Shallow water in 

 the upper districts, and northward. June -July. Panicle 1 long. 



2. G. acutiflora, Torr. Culms slender, ascending, 2 -3 long ; leaves 

 linear ; panicle simple, the short branches distant and erect ; spikelets 5- 12- 

 flowered ; florets subulate ; flowering glume acute, shorter than the long- 

 pointed palet. Shallow ponds, Tennessee. June. 



-i- -i- Spikelets more or less compressed, 3 - 1-flowered. 



3. G. obtusa, Triu. Culms stout, 1- 2 high ; leaves long, linear ; pan- 

 icle oblong, dense, 2' -3' long, the branches in pairs or threes; spikelets 5-7- 

 flowered ; flowering glume obtuse, 5-nerved. Coast of North Carolina. 



4. G. elongata, Trin. Culms slender, 2- 3 long; leaves long, narrowly 

 linear, rough; panicle racemose, drooping, 1 or more long, the branches 

 single; spikelets 2 -4-flowered, ovate, obtuse; flowering glume 5-nerved. 

 Mountains of North Carolina. 



* * Panicle open or diffuse. 



5. G. nervata, Trin. Culms erect ; panicle diffuse, the branches at length 

 drooping; spikelets purplish, very numerous, ovate-oblong, 5-6-flowered, 

 nearly terete ; flowering glume oblong, obtuse, 7-nerved. Swamps and river 

 banks. July. Culms 2 - 3 high. Spikelets 2" long. 



6. G. pallida, Trin. Culms erect or ascending ; panicle narrow, nearly 

 simple, with the branches erect ; spikelets pale, oblong-linear, 5 - 9-flowered, 

 nearly terete; flowering glume oblong, minutely 5-toothed, 7-nerved. Shal- 

 low water, North Carolina and Tennessee. July. Culms l-3 long 

 Spikelets 3" long. 



