322 POACE.E. 



m. Plant 60-90 cm high (r) 



r. Upper ligule 3-5 mm. long, panicle 



raised 20 cm. above the upper leaf. . 2i 

 r. Upper ligule 5-9 mm. long, culm 



60-80 cm. high (s) 



s. Spikelets 2.5-3 mm. long, densely 

 flowering on the upper third of the 



branches 25 



s. Spikelets 3-4 mm. long, rays 

 flowering from about the middle. . 26 

 1. A. Elliottiana Schult. Mant. 2:372 (1824). A. arachnoides 

 Ell. Bot. S. C. & Ga. 1: 134 (1817), not Poir. 

 (1810). 



Culms tufted, weak and slender, 30-50 cm. high. Sheaths 

 scabrous; ligule 3 mm. long; blades narrow, thin, 2-8 cm. long. 

 Panicle exserted, weak and difCuse when mature, rayc scabrous, 

 capillary in remote half-whorls of 3-G, branching above the middle, 

 flower-bearing at and near the tips. Spikelets nearly 2 mm. long; 

 empty glumes subequal, scabrous on the keel, scarcely acute when 

 spread; floral glume 1.5 mm. long, 5-nerved, with 2 minute bristles 

 at the truncate apex, and a very slender flexuose awn 7 mm. long, 

 on the back a little below the apex; palea smaller than its glume 

 or wanting. 



The panicles of this species much resemble those of A. [scahra) 

 hiemalis, but the very slender awns enable us very readily to dis- 

 tinguish one from the other. Possibly it is an awued form of A. 

 hiemalis. 



Tennessee to Texas. April to May and June. 

 2. A. exigua Thurb. S. Wats. Bot. Calif. 2: 275 (1880). 

 A dwarf annual, 3-10 cm. high, sometimes branching near the 

 base. Sheaths very loose; ligule about 2 mm. long, acute; blades 

 4-30 mm. long, mostly convolute, rough. Panicle half the length 

 of the plant, included, at length open, lower rays about 5, others 

 in pairs, the longest 2.5 cm. long, bearing 1-5 spikelets above the 

 middle. Spikelets 1.5 mm. long, empty glumes obtuse, purplish, 

 clothed with minute scattered hairs; floral glume as long as the 



