FE8TUCE.B. 661 



floral glume, it would be placed uear Avma, to which it is closely 

 allied. 



A. Floral glume 2.8-3 mm. long 1 



B. Floral glume 3.5-3.T mm. long 2 



C. Floral glume 4-6 mm. long (a) 



a. Floral glume unawned a 



a. Floral glume awued 4 



1. 0. altyugum Foum. Bull. Soc. Bot. Fr. 24: 182 (1877). 

 An erect rather slender slightly tufted light-colored perennial, 



30-60 cm. high. Sterile shoots few; leaves of the culm 2-3; 

 sheaths smooth, as long as the internodes; ligulo lacerate, truncate. 

 0.7 mm. long; blades nearly smooth, flat, 4-6 cm. long, 1.5-2 mm. 

 long, apex acuminate. Panicle spikelike, slender, slightly inter- 

 rupted, 6-12 cm. long, 3-5 mm. diam., the longest ray about 3 cm. 

 long; flower-bearing from near the base. Spikelets 2-flowered, 

 3.5-4 mm. long; rachilla slightly hairy, produced above the upper 

 floret; first empty glume ovate-lanceolate, 1-nerved, projecting be- 

 yond the rest of the spikelet, second a little shorter and 3-nerved ; 

 floral glume oval, truncate, 5-nerved, 2.8-3 mm. long; palea lance- 

 olate before spreading, as long as its glume. 



Mexico, Pringle 4306. 



Dry ledges under firs. 



2. 0. Pringlei Scribn. ined. 



A slender tufted erect perennial, 40-60 cm. high. Leaves of 

 the culm 3; sheaths and lower side of blades velvety, middle 

 sheath half as long as its intemode; ligule 1 mm. long; blades in- 

 volute or flat, 3-8 cm. long, 1-1.5 mm. wide. Panicle very thin, 

 flexuose, 8-12 cm. long, rays in twos and threes, the longest 4-7 cm. 

 long, bearing a few spikelets on the outer three-fifths. Spikelet? 

 soft, 2-flowered, 6-6 mm. long, first empty glume linear, l-nerved, 

 about 2 mm. long, second elliptical, 3-uerved, 3-4 mm. long; floral 

 glume oval, puberulent on the lower half, 5-nerved, 3.5-3.7 mm. 

 long, truncate-erose, the midnerve often protruding as a mucro; 

 palea 2.5-3 mm. long. 



Mexico, Pringle 4765. 



Summit of Sierra San Felipe at the altitude of 10,000 feet. 



