*74 



GRAMINEAE. 



Vol. I. 



i. Eriocoma cuspidata Nutt. Wild or Indian Millet. Silky Grass. Fig. 413. 



Stipa membranacea Pursh, Fl. Am. Sept. 728. 1814. Not 



L- 1753- 

 Eriocoma cuspidata Nutt. Gen. 1 : 40. 1818. 

 Oryzopsis cuspidata Benth. ; Vasey, Special Rep. U. S. 



Dept. Agric. 63: 23. 1883. 

 O. membranacea Vasey, Grasses S. W. Part 2, pi. 10. 1891. 



Culms glabrous, i°-2° tall, erect, rigid, simple, smooth. 

 Sheaths usually shorter than the internodes, smooth or 

 somewhat rough; ligule i"-2" long, acute; leaves 6'-i2' 

 long, less than 1" wide, involute, stiff, smooth or some- 

 what scabrous; panicle 6'-i° long, diffuse, generally 

 partially included in the upper sheath, its branches 

 widely spreading and many times forked, the ultimate 

 divisions flexuous ; outer scales of the spikelet z"~A" in 

 length, long-acuminate, glabrous; third scale about one- 

 half as long, acute, densely pubescent with long silky 

 erect hairs nearly twice its own length, the awn 2"-$" 

 long. 

 On prairies, Saskatchewan to Washington, Iowa, Texas and Mexico. Bunch-grass. May-July. 



31. ORYZOPSIS Michx. Fl. Bor. Am. i : 51. 1803. 



[Urachne Trin. Fund. Agrost. 109. 1818.] 



Usually tufted grasses, with flat or convolute leaves and paniculate inflorescence. Spike- 

 lets i-flowered, broad. Scales 3; the two lower about equal, obtuse or acuminate; the third 

 scale shorter or a little longer, broad, bearing a terminal awn which is early deciduous, the 

 callus at the base of the scale short and obtuse, or a mere scar. Stamens 3. Styles distinct. 

 Stigmas plumose. Grain oblong, free, tightly enclosed in the convolute scale. [Greek, in 

 allusion to the supposed resemblance of these grasses to rice.] 



About 24 species, distributed through temperate and subtropical regions, rarely extending into 

 the tropics. Besides the following, some 7 others occur in the western parts of North America. 

 Type species : Oryzopsis asperifolia Michx. 



Spikelet, exclusive of awn, i}4"-2" long. 



Awn not 1" long, shorter than the scale; outer scales ij4"-2". 1. O. pungens. 



Awn 3"-4" long, more than twice as long as the scale; outer scales about i J /i" in length. 



2. O. micrantha. 

 Spikelet, exclusive of awn, z"~a" long. 



Culms nearly naked, leaves all crowded at the base ; panicle 2'-3' long, its branches 1' in 



length or less, erect. 3. O. asperifolia. 



Culms leafy to the top; panicle 6'-i2', branches 2'-4' long, spreading. 4. O. racemosa. 



1. Oryzopsis pungens (Torr.) Hitchc. Slender 

 Mountain-rice. Fig. 414. 



Milium pungens Torr.; Spreng. Neue Entd. 2: 102. 1821. 

 Oryzopsis canadensis Torr. Fl. N. Y. 2 : 433. 1843. 

 Oryzopsis juncea B.S.P. Prel. Cat. N. Y. 67. 1888. 

 Oryzopsis pungens Hitchc. Contr. U. S. Nat. Herb. 12: 151. 

 1908. 



Culms glabrous, 6'-2° tall, erect, slender, simple, smooth. 

 Sheaths shorter than the internodes, usually crowded at 

 the base of the culm; ligule about 1" long, decurrent; 

 blades smooth or scabrous, erect, involute, the basal about 

 one-half the length of the culm, occasionally equalling it, 

 filiform, those of the culm i'-4' long, the uppermost often 

 very small or reduced to the sheath only; panicle i'-2i' 

 long, the branches l'-i' in length, erect or ascending, the 

 lower half naked; spikelets ii"-2" long, the outer' scales 

 about equal, glabrous, whitish ; third scale about the same 

 length or a little longer, pubescent with short appressed 

 silky hairs, the awn less than 1" long. 



In dry rocky places, Pennsylvania to Labrador and British 



Columbia. May-June. 



