TRISETUM. 187 



the uppermost imperfect ; lower palet rounded on 

 the back, mostly 5 to Il-nerved 5 bearing a long, usu- 

 ally-bent twisted awn on the back or below the 

 acutely 2-cleft tip proceeding from the mid-nerve 

 only ; stamens 3 ; grain oblong, linear, grooved on 

 one side usually hairy, at least at the top, free but 

 invested by the upper palet. 



The classical Latin name. 



The common oat. Avena Sativa represents the 

 large-flowered annual species of the Old World. The 

 following are smaller-flowered, indigenous peren- 

 nials : 



1. A. Striata (Purple Wild Oat). Rocky, shaded 

 hills, New England, New York, and northward. 



2. A. Smithii (Smith's Oat Grass). Grows from 

 two and a half to four and a half feet high. Woods 

 near Sault Ste., Maine. 



3. A. Flavescens (Yellow Oat grass). See page 58). 



4. A. Pratensis (Meadow Oat grass). Native of the 

 pastures of Great Britain. Flourishes best on dry 

 soils, and furnishes a medium quality of hay. 



50. TRISETUM Persoon. TKISETUM. 



GENERIC CHARACTER. 



Spikelets 2 to several-flowered, often in a contracted 

 panicle, the lower palet compressed-keeled, of about the 

 same membranaceous texture as the glumes, bearing 



