DESCRIPTIONS OF TRIBES AND GENERA. 123 



into two fine, awn-like points ; in the latter into two 

 short, coarse teeth ; the fruit is also shorter and broader. 

 The culture of these two varieties has been given up in 

 most countries on account of the small profits derived 

 from them ; they can be utilized advantageously only on 

 very light, sandy soils. In Portugal, Spain, the Shet- 

 land and Orkney Islands, and in Mechlenburg, Holstein, 

 etc., Hairy oats (A. strigosa) are here and there culti- 

 vated. Both species occur as weeds, however, especially 

 among common oats. 



Sec. II. Avenastrum (Heiiffelia Schur., Helicotrichum 

 Bess.). Perennials. Spikelets upright ; empty glumes 

 five-nerved. A. pubescens, " Downy oats," with downy 

 lower leaves, is a good fodder-grass. [Avena Hookeri 

 Scrib. (A. versicola Hook, non Yill.) with the habit of 

 A. pi*atensis L. is common in the Rocky Mountain region 

 of the Northwest.] 



161. (162) Amphibromus Nees. Spikelets 8-10-flow- 

 ered, loosely panicled ; awns slender, geniculate. 



Species one (A. Neesii Steud.), in Australia. 



162. (163) Arrhenatherum Beauv. Habit of Avena, 

 Sec. II ; but the spikelets are 



somewhat smaller, and the two 

 flowers in each are different (as 

 to sex). The flowering glume 

 of the lower floret is awned 

 from the base, while that of the 

 upper is awned from the point or 

 awuless. 



Species six, in Europe, North- 



em Africa, Western Asia. A. FlG - ^.-Arrhenatherum avena- 



ceum Beauv. (After Nees, Gen. 



avenaceum Beauv. (Avena elatior Germ., 1.49.) 

 L.) (Fig. 64) with expanded panicles and naked, shining 

 spikelets is the French "Bay grass." It is native in 

 Central and Southern Europe, and much cultivated in 

 North America (" Randall grass," " Evergreen grass"), 

 a very good and productive grass for chalky soils. 



163. (161) Gaudinia Beauv. (Arthrostachya Link) (Fig. 

 65). Annuals with the habit of Lolium, and spikelets as 



