662 GRAMINE^E. (GRASS FAMILY.) 



58. ME LIC A, L. MELIC-GRASS. (PL 10.) 

 Spikelets 2 - 8-flowered ; the 1-3 upper flowers imperfect and dissimilar, con- 

 volute around each other, and enwrapped by the upper fertile flower. Empty 

 glumes usually large, scarious-margined, convex, obtuse; the upper 7-9- 

 nerved. Flowering glume papery-membranaceous, dry and sometimes indu- 

 rating with age, rounded or flattish on the back, 5 - many-nerved, scarious at 

 the entire blunt summit. Stamens 3. Perennials with soft flat leaves. Pan- 

 icle simple or sparingly branched ; the rather large spikelets racemose-one- 

 sided. (An old Italian name for Sorghum, from mel, honey.) 



1. M. mutica, Walt. (PI. 10.) Slender, with usually narrow leaves, the 

 panicle often reduced to a simple raceme ; lower glumes nearly equal and 

 almost equalling the spikelet; fertile flowers usually 2; flowering glumes 

 broad, smooth, obtuse. Rich soil, Penn. to Fla., west to Wise., Iowa, and Tex. 



2. M. diflfusa, Pursh. Taller, 2|-4 high, with mostly broader leaves 

 and a more usually compound and many-flowered panicle ; lower glumes more 

 unequal, the outer very broad ; fertile flowers usually 3 ; flowering glumes 

 somewhat scabrous and more acute. (M. mutica, var. diffusa, Gray.) Penn. 

 to 111., and southward. 



59. DIARRHENA, Raf. (PI. 10.) 



Spikelets several-flowered, smooth and shining, one or two of the uppermost 

 flowers sterile. Empty glumes ovate, much shorter than the flowers, coria- 

 ceous ; the lower much smaller ; flowering glume ovate, convex on the back, 

 rigidly coriaceous, its 3 nerves terminating in a strong and abrupt cuspidate 

 or awl-shaped tip. Squamulae ovate, ciliate. Stamens 2. Grain very large, 

 obliquely ovoid, obtusely pointed, rather longer than the glume, the cartilagi- 

 nous shining pericarp not adherent to the seed. A nearly smooth perennial, 

 with running rootstocks, producing simple culms (2-3 high) with long linear- 

 lanceolate flat leaves toward the base, naked above, bearing a few short-pedi- 

 celled spikelets (2 - 3" long) in a very simple panicle. (Name composed of 

 5fs, two, and fyfav, man, from the two stamens.) 



1. D. Americana, Beauv. Shaded river-banks and woods, Ohio to 111., 

 and southward. Aug. 



60. UNiOLA, L. SPIKE-GRASS. (PI. 11.) 



Spikelets closely many-flowered, very flat and 2-edged ; 3-6 of the lowest 

 glumes empty, lanceolate, compressed-keeled ; flowering glume coriaceo-mem- 

 branaceous, strongly laterally compressed and keeled, striate-nerved, usually 

 acute or pointed, entire, enclosing the much smaller compressed 2-keeled palet 

 and the free laterally flattened smooth grain. Stamen 1 (or in U. paniculata 

 3). Upright smooth perennials, growing in tufts from strong creeping root- 

 stocks, with broad leaves and large spikelets in an open or spiked panicle. 

 (Ancient name of some plant, a diminutive of unio, unity.) 



* Spikelets large (--2' long), ovate or oblong, 9 - 30-flowered ; panicle open. 



1. U. paniculata, L. (SEA OATS.) Culm and panicle elongated (4 - 

 8 high) ; leaves narrow, when dry convolute; spikelets ovate, short-pedicelled ; 

 glumes glabrous, bluntish, several of the lower sterile ; stamens 3. Sand-hills 

 on the sea-shore, S. Va. and southward. 



