AGROSTIDE^. 275 



Achnodon Link, Hort. Berol, 1 : 65 (1827). Plantinia Bubaui, iu 

 Xuov. Giorn. Bot. Ital. 5:317 (1873). 



Spikelets 1-flowered, flat and crowded into a cylindrical or ovoid 

 spikelike panicle, racliilla very short, articulation above the lower 

 glumes and sometimes extending beyond the flower as a short spine. 

 Outer glumes 2, persistent, nearly equal, membranous, com- 

 pressed-keeled, 1-3-nerved, subtruncate, the keels projecting into a 

 point or very short awn; floral glume very thin, shorter, broader, 

 truncate or denticulate, enclosing a narrow hyaline palea and a per- 

 fect flower; the palea sometimes containing a minute bristle on the 

 back and near the base. Stamens 3. Styles distinct. Grain ovoid, 

 enclosed by the delicate palea, but not adherent. 



Erect annual or perennial grasses; blades flat; spike borne on 

 a long peduncle, often pubescent. 



A small genus containing about 10 sjiecies found in Europe, 

 Central and Western Asia, Northern Africa, and the northern part 

 of North America. Bentham says: *' It has been proposed to sep- 

 arate generically ChUocldoa Beauv. [Achnodon Link) for the few 

 species in which the rachilla is produced beyond the flower into a 

 minute bristle; the character is, however, in this instance very 

 trifling and uncertain. "" 



1. P. alpinum L. Sp. PI. 50 (1753). Mountain-timothy. 



An erect perennial, 30-00 cm. high. Sheaths two-thirds as 

 long as the internodes; ligule short, truncate: blades smooth or 

 scabrid, 5-8 cm. long. Spike ovoid or oblong, usually tinged with 

 purple, 1.5-3 cm. long. Spikelets oblong, 3-4 mm. long, teeth 

 nearly 2 mm. long, the keels strongly fringed with hairs, empty 

 glumes 3-nerved; floret about 2 mm. long, floral glume 5-nerved. 



Plants from the White Mountains, N. H. ; Montana, Mt. Hood, 

 and Oregon have spikelets 3 mm. long, while some from Colorado 

 have spikelets 4 mm. long. 



Vermont, Hosford for U. S. Dept. Agricul. 341; New 

 Hampshire, Clark 4364; Colorado, Cassidy; ^lontana, Anderson 

 23. Utah, Jones 1201; Alaska, Fnnston for U. S. Nat. Herb. 

 119; British Columbia, Macoun; Oregon, Hoioell; Behring Sea, 

 Merriam. 



