23 



ing from Colorado to New Mexico. In some places they form a 

 considerable proportion of the vegetation, and are eaten by cattle, 

 some of them being considered as next in value to Grama grass, 

 (Bouteloua.) 



^Egoporon, H. B. K. 



Inflorescence in loose, one-sided, terminal and lateral spikes or 

 racemes ; the spikelets are one-flowered in clusters of two or three, 

 one of which is usually sterile or male only. The outer glumes are 

 cuneate, emarginate, aristate, and shorter than the flowering glumes, 

 which are three-nerved and three-awned ; the palets are two-nerved 

 and two-awned. Stamens 3, styles 3. 



1. ^E. cenchroides, Willd. Texas. 



2. ^E. geminiflorus, H. B. K. New Mexico and Arizona. 



Oathbstechum, Presl. 



Spikelets mostly 2-flowered, in fascicles of three, rarely four, each, 

 along the rhachis of a somewhat one-sided simple raceme, which is 

 about 1 inch long, and composed of from 5 to 9 fascicles of flowers. 

 Flowers mostly perfect, or the upper one sterile. Outer glumes 

 unequal, the lower one small, the upper lanceolate, acute, or mucro- 

 nate, flowering glumes oblong, four-lobed, with the 3 nerves ex- 

 tended into short awns between the lobes ; palet 3-toothed at the 

 apex, the two nerves extended into a short point. Low grasses 

 growing in clumps, sending out runners which take root at intervals 

 to form new stools. 



1. C. erectum, Vasey <& Hackel. Texas to Arizona. 



Tragus, Hall. (Lappago, Schreb.) 



Flowers in rather close terminal spikes ; the spikelets in clusters 

 of 2 to 5, mostly 3, one of which is imperfect. The perfect spike- 

 lets are one-flowered, with dissimilar glumes, the lower one minute 

 and membranaceous, the upper one concave, subcartilaginous, and 

 beset with stout, short hooks ; the flowering glume is firmly mem- 

 branaceous and acute ; the palet is shorter and thinner, two-nerved. 

 Stamens 3, styles distinct. 



1. T. racemosus, Hall. Introduced. Rare. 



