86 THE AGRICULTURAL GRASSES OF THE UNITED STATES. 



inches long, narrow, acuminate-joointed, inclined to be involute, tbe 

 vslieaths more or less hairy. The smooth culm has three or four leaves, 

 which are 4 to 8 inches long, and slender-pointed. The panicle is nar- 

 row and spike-like, 6 to 9 inches long, composed of tive or six alternate? 

 somewbat distant, and closely erect branches, the lower ones 1 to 2 inches 

 long, and consisting of six to ten sessile, alternate spikelets, each of 

 which are eight to ten flowered, and four to six lines long. The outer 

 glumes are lanceolate, acute, smooth, nearly equal, somewhat faintly 

 I three-nerved, and three to five lines long ; the flowering glumes are 

 oblong, three-nerved, two to three lines long, entire or obscurely dentic- 

 ulate at the apex, acute or obtusish, the nerves and margins densely 

 hairy for about two-thirds the length, also the base and axis hairy. The 

 palet is one-third shorter, two-keeled, minutely toothed at the apex, 

 hairy on the keels below. * * 



Little is known of its abundance or agricultural value. (Plate 83.) 



Triodia stricta is another species of Texas and the Southwest, much 

 larger, stouter, and more rigid than the preceding. 



Triodia acuminata. (Tricuspis acuminata.) 



A low species, growing in tufts, from 6 to 12 inches high, the leaves 

 short and narrow, but abundant near the ground; the culms are erect, 

 slender, with one or two short leaves, and terminated by an oblong, 

 spike-like panicle about an inch long, composed of a few crowded ses- 

 sile or nearly sessile branches, each with one to three spikelets. The 

 spikelets each contain eight or ten crowded flowers. The outer glumes 

 are nearly equal, lanceolate, acute, chartaceous, one-nerved, about three 

 lines long ; the flowering. glumes are about three lines long, lanceolate 

 or ovate-lanceolate, acute, three-nerved, the mid-nerve extended into a 

 short stiff awn, the margins fringed with long white hairs, and theback 

 below, with the axis, hairy. The palet is about one-third shorter than 

 its glume, folded back on the two keels, sparingly hairy, and the keels 

 scabrous pubescent. This is a native of the arid regions of Texas, New 

 Mexico, and south westward. (Plate 84.) 



Triplasis PURPUREA. (Tricuspis piirpiirea.) (Sand grass.) 



An annual grass, growing in tufts in sandy soil along the Atlantic 

 coast, and also in sandy districts in the interior. The culms are about 

 Ifoot high, rather decumbent at the base, with eight to ten short joints, 

 and an equal number of narrow, awl-shaped leaves, 2 to 3 inches long, 

 which are bearded with hairs at the top of the sheaths. There are usu- 

 ally several lateral panicles of flowers as well as a terminal one. The 

 lateral ones are inclosed within the sheaths; the terminal one usually 

 exerted, but short and simple. The spikelets are two to fiveflovvered; 

 the glumes much shorter than the spikelet ; the flowers rather distant 

 from each other; the flowering glumes and palets strongly fringed on 



