298 POACE^. 



above the ground from a long prostrate portion. Sheaths loose, 

 half as long as the internodes; ligule nearly 2 mm. long; blades 

 thin, scabrid, flat or involute, about 2 cm. long, nearly 1 mm. wide. 

 Panicles terminal and lateral, all more or less included by the 

 sheaths, spikelike, about 1 cm. long. Empty glumes subequal, 1- 

 nerved, very broad, erose, about 0.5 mm. long; floret olive-green 

 tinged with red; floral glume ovate when spread, 3-nerved, 1.5 mm. 

 long; palea like its glume excepting the nerves, which are 2 in 

 number. 



Mexico, Bonrgeau 3285, Tracy from Palmer, Pringle 3317. 



26. S. Shepherd! Vasey, Bull. Torr. Club, 14: 8 (1887). 

 Apparently annual, branching at the base; culms smooth or 



scabrid, 20-40 cm. high. Sheaths loose, about the length of the 

 internodes; ligule lacerate, 2-3 mm. long; blades of sterile shoots 

 few and short, those of the culm 3-4 in number, involute, 4-8 cm. 

 long, 2 mm. or less wide. Panicle exserted, ojDcn, 8-12 cm. long, 

 rays mostly single, the longest 5 cm. long. Si^ikelets often nod- 

 ding on extremely slender pedicels, which are thickened above; 

 empty glumes obtuse when spread, obscurely 1-nerved, first only a 

 little shorter tlian the second, which is 1.5 mm. long; floral glume 

 hairy, oval, 3-nerved, as long as the second glume; palea hairy. 

 broadly oval, obtuse, us long as its glume. 



The plants examined were reddish throughout. 



Mexico, Pringle 1424. 



27. S. asperifolius (Nees) Thurb. ; S. Wats. Bot. Calif. 2:269 

 (1880). Vilfa «s/)m/bZia Meyen, Reise 1 : 349, 408. Trin. Mem. 

 Acad. St. Petersb. (VI.) 6:95 (1840). Sjyorohulus arenaceiis 

 Buckl. Proc. Phila. Acad. 1862, 89 (1863). 



Culms branching, 20-40 cm. high, ascending from stout creep- 

 ing rootstocks. Sheaths smooth, loose, longer tlian the numerous 

 short internodes; ligule very short; blades flat, scabrous, 3-8 cm. 

 long, 2 mm. wide. Panicle included at the base; open, pyramidal, 

 10-17 cm. long ; rays single or in pairs, scabrous, bearing single 

 spikelets at the ends of the very slender stifi' branches. Spikelets 

 lead-color, tinged with purple ; empty glumes colorless, lanceolate, 

 scabrid under a lens, 1-nerved, first 0.3-0.5 mm. long, second but 



