ACillOSTlDE.E. 323 



empty glumes, 5-nerved, scabrous, witli few minute hairs, very 

 acute, terminating in 2 seta?, awn one-fifth below the tips and jsro- 

 jecting 5-6 mm.; palea or minute. Not seen by me. 

 California, BoknuJcr. 



3. A. Howellii Seribn. Vasey, Contrib. U. S. Nat. Herb. 3 : 76 

 (1892). 



Perennial; culms weak, geniculate, 40-60 cm. high. Sheaths 

 smooth, about 4 in number, nearly as long as the internodes; 

 ligule 4-6 mm. long, blades flat, slightly scabrid, 20-30 cm. long, 

 4-5 mm. wide. Panicle greenish white, exserted, diffuse, flexuose, 

 18-20 cm. long, the lower rays in distant half- whorls of 5-7, the 

 upper ones in pairs, capillary, branching at and above the mid- 

 dle, some of them 8 cm. long, flower-bearing near the tips. Sjiike- 

 lets 3-4 mm. long, scabrous on the keels, first glume 3.5 mm. 

 long, a little longer than the second; floral glume 2.5-2.8 mm. 

 long, lacerate-toothed, 4-nerved above, the awn attached below the 

 middle, bent, not flexuose, exceeding its glume by 2-4 mm., hairs 

 0.5-0.7 mm. long; palea 0. 



Oregon, Howell 198. In 1882, distributed as A. ScouUrii Trin. 



Alaska to California. 



4. A. virescens II. B. K. Nov. Gen. et Sp. 1: 135 (1815). 



A stout erect perennial. 30-80 cm. high. Sheaths nearly smooth, 

 the second from the top half as long as the internodes ; ligule trun- 

 cate, about 4 mm. long; blades erect, flat, scabrid, 12-16 cm. long, 

 5-9 mm. wide. Panicle exserted, pale green or brownish, tinged 

 with purple, 15-18 cm. long, 3-4 cm. broad, the rays in clusters 

 of 5-15, distant about 3 cm., the short ones flower-bearing nearly to 

 the base, the longest flower-bearing from about the middle. Spike- 

 lets with empty glumes very acute, scabrid throughout; first glume 

 3.5 mm. long besides a bristle 1 mm. long, second 3 mm. long 

 besides a short bristle; floral glume over 2 mm. long, with a few 

 very short hairs at the base, very broad, truncate, 5-nerved below, 

 the lateral nerves terminating in minute bristles, the awn rather 

 stout, attached near the middle, projecting 4 mm. ; palea 0. 



The plants seen belong to Scribner and were collected by Bolan- 

 der and ticketed "A. viridis, fide Munro. A. pallida fide Thurber." 



