28 POACEAE. 



tuberculate-scabrous; awns equal, 5-7 cm. long. {A. purpurea 

 calif or nica Vasey.) 



Occasional in the lower altitudes of the chaparral belt. 



10. STIPA L. Feather-grass. 



Generally rather tall grasses with convolute, rarely 

 flat leaves and paniculate inflorescence. Spikelets 1- 

 flowered, narrow. Glumes 3, the outer 2 narrow, acute 

 or rarely bearing an awn, the third rigid, convolute with 

 a hairy callus at the base and bearing a more or less 

 bent awn, which is spiral at the base and articulated to 

 the glume. Stamens 3, rarely fewer. Styles short, dis- 

 tinct. Grain narrow, free, tightly enclosed in the glume. 

 Awn villous or pubescent. 



Awn with 1 bend, very villous below the 



bend. 1. S. speciosa. 



Awn with 2 bends, villous to second bend. 2. S. occidentalis. 



Awn scabrous or puberulent. 



Floral glume clothed with hairs 4 mm. long. 



Awn with 2 bends; plant 1 m. high. 3. S. coronata. 



Awn with 1 bend; plant 5 dm. high. 4. 5. parishii. 



Floral glume with hairs 1 mm. long. 



Terminal segment of awn 3.5 cm. long. 5. S. setigera. 



Terminal segment of awn 2 cm. long. 6. 5. eminens. 



1. S. speciosa Trin. & Rupr. Perennial; culms tufted, erect, 

 2-5 dm. high; sheaths shorter than the internodes, the uppermost 

 inflated; basal leaves half as long as the culms, scabrous, culm 

 leaves, usually 3, 5-15 cm. long, closely involute; panicle often 

 somewhat included, spike-like, 6-20 cm. long, the branches usually 

 in pairs, bearing 1-3 spikelets; empty glumes nearly equal, hyaline, 

 acuminate, about 16 mm. long; flowering glumes silky-pubescent, 

 8-12 mm. long, 2-toothed at the apex; awn 3-4 cm. long, geniculate 

 below the middle, the twisted portion pilose with white hairs 3-6 

 mm. long. 



Occasional on dry hillsides in the lower portions of the chaparral 

 belt. San Fernando Valley; Elsinore; San Bernardino; San Diego. 



2. S. occidentalis Thurb. Culms slender, cespitose, 3-6 dm. 

 high; sheaths smooth; ligule 1 mm. long; blades narrow, involute; 

 panicle narrow, 10-20 cm. long; glumes 8-10 mm. long, acuminate, 

 3-nerved, smooth; floral glume 6 mm. long, long-pilose, the callus 

 sharp; awn about 25 mm. long, twice geniculate, pilose to the second 

 bend or throughout, the first section 6-8 mm. long. 



Open pine forests, Mt. Wilson. This is the S. viridula of the 

 first edition. 



3. S. coronata Thurb. Culms 10-20 dm. high, stout, 6-8 mm. 

 thick at the base, lower culm leaves often 10 dm. long, 8-12 mm. 

 wide at base, gradually tapering to a long involute point, the upper- 



