520 POACE.E. 



Annual or perennial grasses, the narrow blades flat or sometimes 

 involute-setaceous. Panicles usually spreading with capillary 

 drooping branches, sometimes narrow, strict or spikelike. 



There are 10-12 species, widely spread over the tem})erate regions 

 of the Northern and Southern Hemispheres. All are characterized 

 by the very concave, sometimes almost vesicular glumes, the grain 

 much flattened from back to front. 



They may be placed in three sections : 



A. Euhriza. Si)ikelets broud in loose panicles with capil- 

 lary pedicels, floral glume obtuse, awnlcss (a) 



a. Spikelets deltoid, empty glumes longer than the first 



floral glume, 3-4 mm. long 1 



a. Spikelets half oval, Gmm. long, empty glinnes shorter 



than the first glunu' 3 



a. Spikelets ovate, 10-1 T mm. long 3 



B. C/i(tsroli/irHt)i Desv. Spikelets awnless, i)anic-le rather 

 compact, spikelets almost sessile. I'anicle rather dense, 

 erect 4 



0. Cnlothrcd Desv. l*uni('le loose and spreading, glumes 

 broa<lly scarious. awned; floral ghunes with projecting 

 lateral angles 



1. H. .MINOR L. Sp. IM. TO (1753). S.MAM.KUQrAKI\(;-()UAS.S. 



B. aspera Knapp. (iram. Brit. f. 61 (1804). //. riridis Pall. 

 iSteud. Xom. Ed. 2. 1 : 220 (1841). 



An erect gracefiil annual, 15-40 cm. Iiigh, ligule :>-() mm. long; 

 blades 5-8 cm. long, 2-4 nun. wide. Panicle erect, open, ])i'oadIy 

 oval, 3-S cm. long, rays in twos or single, branching. Sjukelets 

 deltoid, 4-0-flowered, ;5-4 mni. long: emi)ty glumes subequal, 5- 

 uerved. longer than the first floral glume. 



\'irgiiiia. J\ S. Depf. Jf/n'rtiL 624 from .T. \V. Chickering. Jr.; 

 Oregon (C rant's Pass), IfnireU. 



Foiuul in Europe and northern Africa, aiul sparingly naturalized 

 in North America. 



2. li. MEDIAL. Sp. PI. 70(1753). MkDIUM (^rAKIV(i-(iHASS. 



B. clatior Si1)th. & Sni. Fl. (Iraec. 1 : /. 75 (1 80(i). />'. hthsceiis [Fou- 

 cault, in] Desv. Journ. 3: A 24,/. 2 (1814). /?. Clxsii Schult. U. 



