658 GRAMINE.E. (GRASS FAMILY.) 



2. TRIPLASIS. Glumes much shorter than the somewhat remote flowers ; 

 flowering glume and palet strongly fringe-bearded, the glume 2-cleft at the 

 summit, its mid-nerve produced into an awn between the truncate or awn- 

 pointed divisions. 



2. T. purpurea, Hack. (SAND-GRASS.) Culms many in a tuft from 

 the same annual root, ascending (6 - 12' high), with numerous bearded joints ; 

 leaves involute-awl shaped, mostly short ; panicles very simple, bearing few 

 2-5-flowered spikelets, the terminal one usually exserted, the axillary ones 

 included in the commonly hairy sheaths; awn much shorter than the glume., 

 seldom exceeding its eroded-truncate or obtuse lateral lobes. (Tricuspis pur- 

 purea, Gray.) In sand, Mass, to Va. along the coast, and southward; also 

 L. Erie, near Buffalo, and 111. Aug., Sept. Plant acid to the taste. 



51. DIPLACHNE, Beauv. (PI. 9.) 



Spikelets several-flowered, narrow, erect and scattered along the slender 

 rhachis of the long spicate spikes ; flowers all perfect or the uppermost stami- 

 nate. Empty glumes membranaceous, carinate, acute, unequal ; flowering 

 glume slightly longer, 1 - 3-nerved, 2-toothecl, and mucronate or shortly awned 

 between the teeth. Stamens 3. Styles distinct. Grain free. Coarse grasses, 

 with narrow flat leaves, and several or many slender spikes sessile upon an 

 elongated peduncle. (Name from Snr\jos, double, and &x v ~n> m tne sense of 

 chaff, with reference to the 2-lobed glume.) 



1. D. fascicularis, Beauv. Smooth; leaves longer than the geniculate- 

 decumbent and branching culms, the upper sheathing the base of the panicle- 

 like spike, which is composed of many strict spikes (3 -5' long); spikelets 

 slightly pedicelled, 7 - 11-flowered, much longer than the lanceolate glumes; 

 flowers hairy-margined toward the base, the glume with 2 small lateral teeth 

 and a short awn in the cleft of the apex. ( Leptochloa fascicularis, Grai/.) 

 Brackish meadows, from R. I. southward along the coast, and from 111. south- 

 ward on the Mississippi. Aug. -Sept. 



52. PHRAGMITES, Trin. REED. (PL 11.) 



Spikelets 3 - 7-flowered ; the flowers rather distant, silky-villous at base, and 

 with a conspicuous silky-bearded rhachis, all perfect and 3-androus, except 

 the lowest, which is either neutral or with 1-3 stamens, and naked. Glumes 

 membranaceous, shorter than the flowers, lanceolate, keeled, sharp-pointed, 

 very unequal ; flowering glume and palet membranaceous, slender, the glume 

 narrowly awl-shaped, thrice the length of the palet. Squamulre 2, large. 

 Styles long. Grain free. Tall and stout perennials, with long running root- 

 stocks, numerous broad leaves, and a large terminal panicle, (^pay/nires, 

 jrowing in hedges, which this aquatic grass does not.) 



1 . P. communis, Trin. Panicle loose, nodding ; spikelets 3 - 5-flowered ; 

 flowers equalling the beard. Edges of ponds. Sept. Looks like Broom- 

 Corn at a distance, 5-12 high; leaves 2' wide. (Eu.) 



53. ARUNDO, L. 



Flowers all perfect ; flowering glume bifid, short-awned oetween the teeth. 

 Otherwise as Phragmites. (The Latin name of the species.) 



