356 



POACEiE. 



iug, rays smooth, rather distant, hearing spikelets above the middle. 



Spikelets compressed, 5-6 mm. long; first 

 glume cuneate, 4-5 mm. long, second 

 lance-linear ; floral glume as long as the 

 second glume, cuneate-lanceolate, hairs 

 copious, straight, two- tliirds as long as the 

 palea. 



Sands about the Great Lakes and in 

 the interior part of British America to 

 Colorado and Arizona. Of some use as a 

 fodder-plant. 



71. (138). Apera Adans. Fam. 2: 

 495 (17G3). Anetnagrostis Triu. Fund. 

 Agrost. 128 (1820). 



Annual; spikelets 1-flowered, small, 

 in an elegant loose panicle with numer- 

 ous slender branches, the rachilla articu- 

 late above the empty glumes and pro- 

 duced beyond the j^erfect flower as a short 

 bristle. Empty glumes persistent, deli- 

 cately membranous, keeled, pointed, but 

 awnless, the second one larger, 3-nerved; 



^ „^ ^ , .,„ . floral glume a little shorter, membranous, 



Fig. 60. — Calamovilfa longi- ° 



folia. A, spikelet; a, floret, witii a slender flexuose dorsal awn below 



crijuei.) ^1^^ 2-toothed apex; palea thin, shorter 



than its glume, 2-keeled, 2-toothed. Stamens 3. Styles distinct, 

 short. Grain narrow, enclosed, but not adherent. 



Blades flat, narrow; panicle terminal, diffuse or contracted. 



Species or perhaps varieties, two, found in Europe, western 

 Asia and northern Africa. 



The characters come very near those of Calamagrostis, while 

 the elegant panicle and numerous glabrous spikelets resemble 

 many species of Agrostis, where the species lias often been 

 placed. 



1. A. Spica-venti (L.) Beauv. Agrost. 151 (1812). Silky 

 Agkostis. Agrostis Spica-venti L. Sp. PL 61 (1753). A. pur- 



