GRAMINE^E. (GRASS FAMILY.) 567 



4. U. nitida, Baldw. Panicle short, of few rigid spreading branches ; 

 spikelets (6" -8" long) oblong, 6-8-flowered; palese equal, the lower acute, 

 serrulate near the apex ; stamen 1 . Swamps, Florida, Georgia, and westward. 

 Aug. Culms slender, l-2 high. Leaves linear, smooth. 



37. PHRAGMITES, Trin. REED. 



Large perennial marsh grasses, with broad and flat leaves and panicled spike- 

 lets. Spikelets 3 - 6-flowered, with the rachis bearded with long and silky hairs. 

 Lowest flower with a single stamen and imperfect ovary, the others triandrous 

 and perfect. Glumes unequal, pointed. Lower palea narrowly awl-shaped, 2-3 

 times as long as the 2-cleft upper one. Stigmas 2. Grain free. 



1. P. COmmunis, Trin. Culms -5 -8 high; leaves numerous, l'-2' 

 wide ; panicle diffuse, nodding ; spikelets 3 - 5-flowered, about as long as the 

 white hairs of the rachis. Deep river marshes near the coast, Florida, and 

 northward. Sept. 



38. ELYMUS, L. LYME-GRASS. 



Coarse flat-leaved perennial grasses, with rigid erect culms, bearing a single 

 spike of 2 - 7-flowered spikelets, arranged 2 - 4 in a cluster at each joint of the 

 zigzag rachis. Glumes 2, placed side by side before the spikelets, coriaceous, 

 unequal-sided, mostly awned. Palese of the same texture as the glumes, the 

 lower convex on the back, tapering into a rigid awn ; the upper enclosing the 

 linear hairy-tipped grain. Stamens 3. Stigmas 2. 



1. E. Virginieus, L. Spike dense, erect (3' long), the base usually 

 included in the dilated sheath of the uppermost leaf ; spikelets 2 - 3 in a cluster, 

 2 - 3-flowered, smoothish, short-awned ; glumes lanceolate, strongly nerved. 

 River-banks, Florida, and northward. July and Aug. Culms 2 3 high. 

 Leaves rough. Sheaths smooth. 



2. E. StriatUS, Willd. Spike dense, erect or slightly nodding (3' -5' long), 

 long-pedunclcd ; spikelets 2-3 in a cluster, 1 - 3-flowered, hairy, long-awned ; 

 glumes linear-subulate, long-awned, much longer than the flowers. Rocky 

 woods and banks in the upper districts, and northward. July -Sept. Culms 

 slender, 2 high. Leaves and sheaths smooth or pubescent. 



39. GYMNOSTICHUM, Schreb. 



Spikelets 2 - 3 on each joint of the rachis, raised on a short and thick stalk. 

 Glumes none, or a single awn-like rudiment. Otherwise as in Elymus. 



1. G. Hystrix, Schreb Spike erect, 3' - 6' long, lax-flowered ; spikelets 

 yellowish, 3 - 4-flowered, smooth or rough-hairy, long-awned ; leaves and sheaths 

 smoothish. (Elymus Hystrix, L.) Upper districts, Georgia, and northward. 

 July. Culms 2 - 3 high. Rachis 2-edged. 



