65B GRAMINE^. (grass FAMILY.) 



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

 flowering (jlume 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-Gkass.) 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-toothed, 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 ZnrX'jos, double, and axv-q, in the sense of 

 chafl\ 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, Gray.) — 

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

 ward on the Missi.ssippi. Aug. -Sept. 



52. PHRAGMITES, Trin. Reed. (PI. 11.) 



Spikelets 3 - 7-floAvered ; 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 tlie length of the palet. Squamulag 2, large. 

 Stj'les long. Grain free. — Tall and stout perennials, with long running root- 

 stocks, numerous broad leaves, and a large terminal panicle. {^payfi'iTes, 

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



1 . P. comraunis, 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.) 



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