MANUAL OF THE GRASSES OF THE UNITED STATES 



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row, open, rather stiffly upright, 10 

 to 20 cm. long, the branches stiffly 

 ascending, 4 to 8 cm. long; spikelets 

 erect or narrowly ascending on the 

 branchlets; first glume 5 to 7 mm. 

 long, the second 7 to 10 mm. long; 

 lemma about as long as the second 

 glume, or slightly longer, tapering 

 into a scabrous slightly twisted beak 

 about 2 mm. long; awns about equal, 



abruptly long-awned, the first 4 mm. 

 long, the second 8 to 10 mm. long, 

 the awns usually 10 to 12 mm. long; 

 lemma 5 to 6 mm. long, extending 

 into a slender twisted column 1 to 

 3 cm. long; awns about equal, 2 to 

 3 cm. long, divergent or horizontally 

 spreading, more or less curved or 

 warped at base. 21 — Pine barrens 

 along the coast, South Carolina to 



Figure 691. — Aristida pansa, 

 N. Mex.) 



X 1. (Wooton, 



divergent or finally nearly horizon- 

 tally spreading, 10 to 20 mm. long, 

 the bases finally somewhat curved 

 or warped. % — Plains and open 

 ground, western Texas to Arizona; 

 northern Mexico. 



21. Aristida spiciformis Ell. (Fig. 

 692.) Perennial; culms strictly erect, 

 50 to 100 cm. tall; blades erect, flat 

 or usually involute, elongate, 1 to 3 

 mm. wide; panicle erect, dense and 

 spikelike, 10 to 15 cm. long, more or 

 less spirally twisted; glumes unequal, 



Figure 692. — Aristida spiciformis, X 1. (Combs and 

 Baker 1115, Fla.) 



Florida and Mississippi ; Cuba, Puerto 

 Rico. 



22. Aristida glauca (Nees) Walp. 

 Reverchon three-awn. (Fig. 693.) 

 Perennial; culms erect, 20 to 40 cm. 

 tall; blades involute, mostly curved 

 or flexuous, 5 to 10 cm. long, about 

 1 mm. thick; panicle narrow, erect, 

 rather few-flowered, mostly 8 to 15 

 cm. long, the branches stiffly ap- 

 pressed; first glume 5 to 8 mm. long, 

 the second about twice as long; lem- 

 ma 10 to 12 mm. long, tapering into 



