ANDROPOGONE^. 31 



The wavy cell-walls of tlie palea aud the fourth glume are 

 conspicuous under a lens. In the jjedicellate spikelets, first glume 

 flat, ovate, 9-11-nerved, over 2 mm. long, a winged keel near 

 one margin, second glume as long as the first, compressed, keeled? 

 5-nerved, third glume as long as the others, hyaline, 2-nerved. 

 Fla., Curtiss dQ'2'l: G. V. Nash\0'!4.. 



2. M. corrugata (Baldw.) Kuntze, Rev. Gen. PI. 779 (1891). 

 R. corrugata Baldwin, Sill. Am. Journ. 1 : 355 (1819). 

 Culms robust, compressed, 90-120 cm. high. Lower sheaths 



compressed, equitant; ligule very short; lower blades 50 cm. 

 long, 5-8 mm. wide, the upper shorter. Spikes projecting above 

 the sheaths, 6-10-15 cm. long, 3-4 mm. diam., cyindrical. Ses- 

 sile spikelets about as long as the joints of the rachis, first glume, 

 including the callous base, 5 mm. long, concave, ovate, bifid, nerves 

 indistinct, vertically and transversely rugose, second glume about 

 4 mm. long, third glume about 3.5 mm. long, 2-nerved, fourth 

 glume as long as the third. Pedicellate spikelets nearly 3 mm. 

 long, first glume ovate, 6-nerved, a keel near one edge, second 

 glume compressed, keeled, 3-nerved. 



Low pine barrens near the coast. South Carolina to Texas. 



3. M. cylindrica (Michx.) Kuntze, 1. c. Tripsacum cylindri- 

 cum Michx. Fl. Bor. Am. 1 : 60 (1803). 



R. crjUndrica Torr. Bot. Whippl. Exped. 159 (1857). 



Culms slender, terete, simple, 60-90 cm. high. Sheaths gla- 

 brous, terete or subcompressed ; ligule very short, ciliate; blade 

 15-40 cm. long, 2-3 mm. broad. Spikes single, projecting, terete, 

 10-18 cm. long, 2.5 mm. wide. Spikelets sessile, 6-7 mm. long, 

 with a callus 1 mm. long; first glume of the sessile spikelets obtuse, 

 7-nerved, 6-8 mm. long, very firm, bifid, nerves inconspicuous, con- 

 cave, with slight pits on the outside; second and third glumes 4 

 mm. long. Anthers 3 mm. long. The pedicellate spikelets rudi- 

 mentary, consisting of 2 small glumes 1.5-2 mm. long. 



Texas, Hall 84:3; Fla., Chajnnan. 



Dry sandy soil, Florida to Texas. 



4. M. compressa (L. f.) Kuntze, 1. c. 



