2. Sporobolus flexuosus (Thurb.) Rydb. Mesa dropseed. 



Tufted perennial; culms 3-10 dm. long, 1-2 mm. thick, erect, unbranched; 

 ligule a ciliate fringe 0.3-0.5 mm. long; blades 5-23 cm. long, 2.4 mm. broad at, 

 the base where flat but usually soon involute; sheaths obscurely round-keeled 

 apically, the corners with some soft white hairs but the dorsal summit or collar 

 glabrous or only very sparsely furnished with hairs, 1-1.5 mm. long; panicles 

 12-30 cm. long, 4-9 cm. broad, basally sometimes partially included in the 

 uppermost sheath, open, the branches not whorled, divaricate or even somewhat 

 deflexed and then arcuately reflexed distally, the floriferous branchlets subsecund 

 on the lower side of the branches, mostly widely divergent from the branches, 

 the spikelets borne on tertiary pedicellary branchlets about 1 mm. long which 

 are subsecund along the proximal side of the secondary branchlets; first glume 

 1-1.3 mm. long; second glume 1.9-2.5 mm. long; lemma 1.9-2.3 mm. long; 

 palea about equaling lemma. 



Loose usually blowing sand in dune areas, also in marshes and wet seepage 

 areas, in the Tex. Trans-Pecos, locally frequent, N. M. (widespread) and Ariz. 

 (Apache, Navajo, Coconino, Yavapai, Graham, Cochise and Pima cos.), Sept.- 

 Nov., rarely also in spring; w. Tex. to s. Ut., Nev., s. Calif, and n. Mex. 



3. Sporobolus virginicus (L.) Kunth. Coastal dropseed. 



Perennial from scaly creeping stramineous rhizomes 1-3 mm. thick; aerial 

 culms mostly ascending or the lowermost internodes stoloniform, 7-40 cm. long, 

 1-3 mm. thick, leafy; ligule a ciliate scale 0.2-0.4 mm. long; blades 3-20 cm. 

 long, usually flat at the very base or rounded-keeled and 2.5-4 mm. broad, 

 tapering to an involute point; corners of sheaths sparsely pilose and upper part 

 of sheath dorsally keeled; panicle 25-80 mm. long, 6-10 mm. broad, dense, 

 spikelike or usually narrowly ellipsoidal or oblong-ellipsoidal; first glume 1.3-2.8 

 mm. long; second glume 1.8-3 mm. long; lemma 2.1-3 mm. long; palea about 

 as long as lemma. 



Packed loamy somewhat saline soil, in saline marshes, sandy or muddy sea- 

 shores and wettish coastal prairies, all along the Tex. coast, common, summer- 

 fall; warmer Atl. and Carib. coasts, s. to Braz. and n. to Va. 



4. Sporobolus indicus (L.) R. Br. Smutgrass. Fig. 118. 



Tufted perennial; culms 3-1 1 dm. long, 1-3 mm. thick, erect, unbranched; 

 ligule obsolete or only a scale 0.1 mm. long; blades aggregated at the base of 

 the plant, 15-25 (-50) cm. long, at the base usually flat or sharply folded, 3-5 

 mm. broad, tapering to a long involute arcuate tip; upper part of the sheaths 

 usually dorsally keeled; panicles 1-4 dm. long, 5-10 mm. thick, dense, spikelike, 

 often somewhat interrupted in the lower part; first glume 0.4-0.9 mm. long; 

 second glume 0.8-1.3 mm. long; lemma 1.4-2 mm. long; palea 1.2-1.8 mm. 

 long; pericarp mucilaginous, the grain often sticking persistently instead of falling 

 readily as in many dropseeds. In some works erroneously called S. Poiretii. 



Mud and moist loam, low prairies and swales, in shallow water and mud 

 about ponds and springy areas, in s.e. Okla. {Waterfall) and e. and s.e. Tex., 

 s.w. to Bexar, DeWitt, Goliad and Aransas cos., frequent, late spring-Nov.; 

 widely distributed in the warmer parts of the world, nat. to the Old World; in 

 Am. occurring n. to Va., Tenn., Ark. and Okla. 



35. Leptochloa Beauv. Sprangletop 



Annuals; spikelets 3- to 12-flowered, the lower 1 or 2 florets perfect, the 

 rest staminate or neutral; spikelets sessile and overlapping, appressed in two rows 

 along one side of a nearly terete rachis (the rachis with its two rows of spikelets 

 being called a "raceme," the total inflorescence being a panicle of 4 to 90 of 



252 



