AGKOSTIDE^. 245 



der, contracted, 5-10-20 cm. long, longest rays appressed, 1-G cm. 

 long. Spikelets subsessile or on pedicels 1-3 mm. long; empty 

 glumes mostly subequal, mucronate, 1-nerved, two-thirds as long as 

 tlie floret; floral glume thinly hairy on the lower half, ovate, abrupt- 

 ly short-mucronate, or bearing a slender awn 1-6 mm. long, 3- 

 nerved, 1.5-2 mm. long; palea as long as its glume. 



The eastern plants have an awnless floral glume; those from 

 Texas have the awn. 



Alabama, 31ohr. 



Open rocky woods, New England to Texas. 



13. M. breviseta Griseb. Hemsl. Biol. Centr. Am. Bot. 3:539 

 (1880). 



A densely tufted perennial, branching near the base, 10-18 cm. 

 high. Ligule 0.5 mm. long; blades glabrous, involute, recurved, 

 1.5-3.5 cm. long, 1-1.5 mm. wide. Panicle simple, linear, the 

 base included by the sheath, 1-3 cm. long, longest rays half as long, 

 each bearing 1-3 spikelets. Spikelets linear, 1.2-1.5 mm. long, 

 tinged with violet; empty glumes ovate, acute when spread, 1- 

 nerved, first 0.6 mm. long, second 1 mm. long; floral glume cilio- 

 late on the margins, ovate when spread, mucronate, 3-nerved, 1.5 

 mm. long. 



Mexico (Michoacan), Pringle 3944; also, according to Fournier, 

 Muhl., numbers 1453, 2003, 2093; Shaffner 111. 



Dry cool soils, and hills. 



14. M. Sehreberi Gmel. Syst. 171 (1747). Drop-seed. Nimble 

 Will. M. dif/im Schreb. Besch. Griis. 2:143, t. 51 (1772-79). 

 Dilepyriim mimdiflorum Michx. Fl. Bor. Am. 1: 40 (1803). 



Culms slender, hard, diffuse, much-branched, sometimes genicu- 

 late, 20-60 cm, high, from knotted rootstocks. Sheaths shorter 

 than the internodes; ligule very short; blades flat, thin, scabrid, pun- 

 gent-pointed, 3-8 cm. long, 2-3 mm. wide. Panicles terminal and 

 lateral, slender, contracted, rather loosely many-flowered, 10-18 cm. 

 long; rays slender, in twos and threes, very unequal, the longest 4-5 

 cm. long; spikelets subsessile or on short pedicels; empty glumes 

 very minute, first obsolete, second truncate ; floral glume sparingly 



