168 



Fig. 136. Asperella hystrix (L.) Humb. (Elymus lu/stri.r Lin.: Asprella W.; 

 Gymnostiehum hystrix Schreb.). BOTTLE BRUSH.— «, A spikelet; b.agpikelet 

 without empty glumes at the base. Another species of this genus is illustrated 

 by fig. 626 in Bui. 17. 



136. ASPERELX.A Humb. in Roem. and Ust. Mag. Bot. 7 : 5. 1790. Spikelets 2- 

 to 4-flowered, solitary or more often 2 to 3 together, raised on short, callus-like 

 pedicels, at each joint of the continuous rachis; rachilla articulated below each 

 flowering glume. Empty glumes 1 or 2, awn-like or bristle-form, usually present 

 in the lower spikelets of each spike, much reduced or entirely wanting in the 

 upper; flowering glumes narrow, rigid, smooth, and rounded on the back, long- 

 awned from the apex. Palea strongly 2-keeled. Perennials with flat leaves 

 and terminal, bearded spikes. 



Species 4, two North American and two of limited range in the Old World. 



