520 POACE^. 



Annual or perennial grasses, the narrow blades flat or sometimes 

 involute-setaceous. Panicles iisnally spreading with caj)illary 

 drooping branches, sometimes narrow, strict or spikelike. 



There are 10-12 species, widely spread over the temperate 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. Spikelets broad in loose panicles with capil- 

 lary pedicels, floral glume obtuse, awnless (a) 



a. Spikelets deltoid, empty glumes longer than the first 



floral glume, 3-4 mm. long 1 



a. Spikelets half oval, 6 mm. long, empty glumes shorter 



than the first glume 2 



a. Spikelets ovate, 10-17 mm. long 3 



B. Chascolytnim Desv. Spikelets awnless, panicle rather 

 compact, spikelets almost sessile. Panicle rather dense, 

 erect 4 



C. CalotJieca Desv. Paiiicle loose and spreading, glumes 

 broadly scarious, awned; floral glumes with projecting 

 lateral angles 



1. B. MINOR L. Sp. PL 70 (1753). Smaller Quaking-grass. 

 B. aspera Knapp. Gram. Brit. t. 61 (1804). 7?. viridis Pall. 

 Steud. Norn. Ed. 2. 1: 226 (1841). 



An erect graceful annual, 15-40 cm. high, ligule 3-6 mm. long; 

 blades 5-8 cm. long, 2-4 mm. Avide. Panicle erect, open, broadly 

 oval, 3-8 cm. long, raj's in twos or single, branching. Spikelets 

 deltoid, 4-6-flowered, 3-4 mm. long; empty glumes subefpuil, 5- 

 nerved, longer than the first floral glume. 



Virginia, U. S. Dept. Agrimd. 624 from .1. W. Chickering, Jr.; 

 Oregon (Grant's Pass), Howell. 



Found in Europe and northern Africa, and sjmringly naturalized 

 in North America. 



2. B. MEDIA L. Sp. PI. 70 (1753). Medium Quakixg-grass. 

 B. elafior Sibth. & Sm. Fl. Graec. 1 : /". 75 (180(5). B. h/fescens [Fou- 

 cault, ill] Desv. .Touni. 3:/. 24,/. 2 (1814). ri. Chisii Scluilt. R. 



