AVENA. 177 



situations as the A. pracox, but does not produce its 

 flowers till a month later. It is found in sandy pastures 

 and heaths throughout England, Germany, France, and 

 Italy. 



The Aira family is very widely diffused in various 

 climates and at different altitudes. The South Sea 

 Hair-grass [A. Antarctica) is found in the South Shet- 

 land Isles, 62° S. latitude, at an elevation of 7046 feet 

 above sea-level. It is frequent in New Zealand. It 

 resembles our native species in its spreading panicle, but 

 has flat leaves and three florets in the spikelets. 



Genus XVIII. AVENA. 



Gen. Char. Spikelets many-flowered, loosely collecting 

 the florets ; outer glumes lanceolate, acute, ventricose, 

 loose, awnless ; flowering glumes slightly smaller, two-cleft 

 at the top, awned ; scales two ; ovary blunt ; styles two, 

 reflex, hairy ; stigmas simple ; filaments three, capillary ; 

 seed oblong, slender, pointed, marked with a longitudinal 

 furrow, clothed with the flowering glume and palea. 



1. Avena fatua, Linn. Wild Oat. 



Root annual, fibrous, thickened at the base ; stem erect, 

 simple, striated, very smooth, three feet high, polished, a 

 little leafy; leaves linear, flat, nervose, scabrous, rough; 

 sheaths thin, nervose, smooth ; panicle erect, much branched, 

 spreading ; rachis smooth ; branches alternate, hair-like, 

 thickened toward the apex, nodding ; outer glumes equal, 

 lanceolate, acute, narrow, smooth, longer than the floret ; 

 florets generally three, remote, gradually diminishing, w T ith 

 tufts of hair at the base ; flowering glumes ovate, acute, 

 eight-ribbed, awned; awn twice the length of the outer 

 glumes, jointed, twisted at the lower end, arising a little 



N 



