MANUAL OF THE GRASSES OF THE UNITED STATES 



453 



times with a smooth neck and a ciliate 

 crown (as in S. leucotricha) ; awn 7 to 

 9 cm. long, short-pubescent to the 

 second bend, the first segment 1.5 

 to 2 cm. long, the second shorter, 

 the third 4 to 6 cm. long. % — 

 Open ground, northern California to 

 Baja California, mostly in the Coast 

 Ranges. 



the branches ascending, few-flowered, 

 naked below; glumes about 1 cm. 

 long, broad, rather abruptly nar- 

 rowed into a short point, 7- to 9- 

 nerved; lemma 7 to 8 mm. long, 

 oblong-elliptic, brown, minutely pap- 

 illose and brownish pubescent, the 

 callus 1 mm. long; awn about 3 cm. 

 long, obscurely twice-geniculate. % 



Figure 64 . — Stipa cernua. Glumes and floret, X 5. 

 (Hall 2921, Calif.) 



Figure 650. — Stipa 

 pringlei. Floret, X 1; 

 lemma, X 5. (Hitch- 

 cock 7691, Mexico.) 



Figure 651. — Stipa em- 

 inens. Floret, X 1 ; 

 lemma, X 5. (Palmer 

 523, Mexico.) 



12. Stipa cernua Stebbins and 

 Love. (Fig. 649.) Culms mostly 60 

 to 90 cm. tall, in rather large clumps; 

 basal blades numerous, narrow, glau- 

 cous, those of the culm 1.2 to 2.4 mm. 

 wide; panicle open with slender flex- 

 uous branches; glumes acuminate, 

 the first 12 to 19 mm. long, the second 

 a little shorter; lemma 5 to 10.5 mm. 

 long, papillose, silky-pilose below and 

 on the nerves, the callus acute, 

 densely bearded; awn 6 to 11 cm. 

 long, the terminal segment flexuous. 

 % — Foothills of Sierra Nevada and 

 Coast Ranges, Calif. 



13. Stipa pringlei Scribn. Pringle 

 needlegrass. (Fig. 650.) Culms, 

 about 1 m. tall; ligule about 2 mm. 

 long; blades 10 to 30 cm. long, 1 to 3 

 mm. wide, flat or those of the innova- 

 tions involute, firm, erect, scabrous, 

 panicle nodding, 10 to 15 cm. long, 



— Rocky woods and slopes, Texas, 

 New Mexico, and Arizona to Chihua- 

 hua, Mex. 



14. Stipa eminens Cav. (Fig. 651.) 

 Culms slender, rather wiry, 80 to 120 

 cm. tall; ligule 3 to 6 mm. long; 

 blades mostly elongate, flat or invo- 

 lute, 1 to 4 mm. wide; panicle nod- 

 ding, open, 10 to 20 cm. long, usually 

 densely pilose on the lower node, the 

 branches slender, spreading, often 

 flexuous, usually 3 to 4 or even more 

 at the node; glumes about 1.5 cm. 

 long; lemma pale, 5 to 7 mm. long, 

 pubescent; awn 3 to 6 cm. long, ob- 

 scurely twice-geniculate, the third 

 segment flexuous. % — Rocky 

 hills, Texas to Arizona and central 

 Mexico. 



15. Stipa lepida Hitchc. Foothill 

 needlegrass. (Fig. 652.) Culms slen- 

 der, puberulent below the nodes, 60 



