, I'lIK (iKASSKS Ml TlNNKSSKK. 101 



1. Melica mutica Walt. 



I'latr XXXIV. Viirurr i:U5. 



A smooth. sleiulcM-, erect j^rass one to three feet hi^h, with nar- 

 row leaves and noddinj;- spikelets in nearly simple panicles. Pani- 

 cle few-flowered, sparinj^jly branched below, often reduced to a 

 simple raceme. Spikelets four to five lines long, with two perfect 

 flowers; empty glumes thin and membranous, subequal, about as 

 long as the spikelet. 



Dry open woods. April — May. 



A/, diffusa Pursh, which may occur within the State, has a more 

 branched panicle, unequal empty glumes, which are decidedly 

 shorter than the three- to four-flowered spikelets. 



49. DIARRHENA Ratin. In Journ. Phys. LXXXIX. 104. (1819.) 



Spikelets three- to five-tlowered, few in a narrow simple panicle, 

 rachilla articulated above the empty glumes and between the 

 florets, lower florets perfect, the uppermost one or two sterile. 

 Empty glumes unequal, ovate, awnless, shorter than the florets. 

 Flowering glumes broader, subcoriaceous, rounded on the back, 

 smooth, and shining, three-nerved, acuminate or mucronate- 

 pointed. Palea rather broad, two-keeled. Stamens two, or rarely 

 only one. Styles short, distinct; stigmas plumose. Grain larger, 

 usually exceeding the palea and glume, obliquely ovoid and ob- 

 tusely-pointed. Nearly smooth perennials, with simple culms 

 from a creeping root-stock, flat leaves and few-flowered terminal 

 panicles. 



Species two, one in Japan, the other in eastern North America. 



I. Diarrhena Americana Beau v. Twin -grass. 

 Plate XXXV. Figure 137. 



An erect perennial two to three feet high, with long, narrow- 

 lanceolate nearly erect leaves and a few-flowered simple panicle, 

 four to ten inches long. Sheaths scabrous, or sometimes pubes- 

 cent above; ligule very short, rigid; leaf-blade six to twenty-four 

 inches long, five to twelve lines wide, tapering to a narrow base, 

 very long acuminate-pointed. Panicle-branches erect. Spikelets 

 three to five lines long, three- to six-flowered, the uppermost 

 flowers imperfect; flowering glumes three-nerved, abruptly and 

 sharply acuminate-pointed. Palea broad, two-keeled, keels sca- 

 brous. Grain about three lines long, enlarged near the middle. 

 Floral glumes spreading in fruit. 



"Rich soil among rocks, here and there." — Gattinger. 



50. UNIOLA Linn. Sp. PI 71 (i753-) 



Spikelets three- to many-flowered, the uppermost one or two 

 staminate or neuter, those below perfect; rachilla articulated 

 above the empty glumes and between the florets. Empt}' 

 glumes at the base of the spikelet three to six. compressed-keeled, 

 acute, unequal. Flowering glumes firm-membranaceous, com- 



