94 Bulletin VII. 1. 



into three mucronate points. Palea broad, concave, with two 

 nearly marginal nerves. Stamens three. Styles short, stigmas 

 plumose. Grain free. Perennial grasses with narrow leaves and 

 variable habit. 



Species about twenty-five, widely distributed throughout the 

 temperate zones, with a few in tropical America. Nearl)^ half the 

 entire number of species occur in the United States, chiefly in 

 Texas and the southwestern Territories. 



I. Triodea cuprea Jacq. (Poa seslerioides Michx.) False or Tall 

 Red-top. 



Plate XXXI. Figure 122. 



A stout, erect perennial three to five feet high, with long flat 

 leaves and an ample spreading, usuall}' purple panicle six to twelve 

 inches long Culm leaves and sheaths glabrous; the sheaths at the 

 base of the culm usually crowded and somewhat compressed. 

 Lower leaves one to two feet long, about one-fourth of an inch wide, 

 very acute, usually hairy near the base; ligule very short, ciliate. 

 Panicle ovate pyramidal, the widely spreading and drooping 

 branches solitary or in pairs, naked below, axils bearded. Spike- 

 lets four- to seven-flowered, three to five lines long; empty glumes 

 thin, broadly ovate, acute one-nerved, the larger second glume about 

 two lines long; floral glumes about two lines long, three-nerved, 

 oblong, hairy on the back below and on the marginal nerves for two- 

 thirds their length, apex of the glumes four-lobed, the nerves pro- 

 jecting a little between the lobes. Palea a little shorter than the 

 glumes, the keels strongly arched. 



A showy grass frequent in dry sandy fields, blooming from Au- 

 gust to October. Apparently of no agricultural value. 



46. ERAGROSTIS Beauv. Agrost. 70 (1812.) 



Spikelets two- to man3^-flow^ered, the uppermost flower imper- 

 fect, rachilla articulated, but sometimes not breaking up until 

 after the fall of the fruiting glumes. Inflorescence variously 

 paniculate, now close and narrow, the spikelets nearly sessile and 

 crowded, now loosely and widely spreading. Empty glumes two, 

 more or less unequal, usually shorter than the floral glumes. 

 Flowering glumes glabrous, obtuse or acute, awnless, three-nerved, 

 lateral nerves sometimes very faint. Paleas shorter than their 

 glumes, two-nerved, nerves prominent, often persistent after the 

 fall of the fruiting glume. 



Annual or perennial grasses with herbaceous stems, of various 

 habit, from two to four inches to as many feet tall, much-branched, 

 or with simple culms. 



Allied to Poa, but with three-nerved flowering glumes, which 

 are destitute of any w)olliness. The species are very variable 

 and their limits hard to define. 



Species about one hundred, in warm and temperate regions of 

 both hemispheres. Tennessee species, including those introduced, 

 nine. 



