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MANUAL OF THE GRASSES OF THE UNITED STATES 



long; first glume minute, the second 

 as long as the lemma and palea. % 

 (S. argutus Kunth.) — Sandy or 

 gravelly soil, especially along streets 

 and along the seashore and in the 

 interior in alkaline soil, Kansas and 

 Colorado to Louisiana and Texas; 

 southern Florida; tropical America. 

 20. Sporobolus domingensis 

 (Trim) Kunth. (Fig. 609.) Perennial; 

 culms erect, 20 to 100 cm. tall; leafy 

 at base; blades rather firm, mostly 

 5 to 20 cm. long, 3 to 8 mm. wide, 

 drying subinvolute, panicle pale, most- 

 ly 10 to 15 cm. long, the branches 

 ascending or appressed; spikelets 



Figure 608. — Sporobolus pyramidatus. Panicle, X 1 ; 

 glumes and floret, X 10. (Hitchcock 5343 ,Tex.) 



Figure 607. — Sporobolus purpurascens. Panicle, X 1; 

 glumes and floret, X 10. (Hitchcock, Tex.) 



Figure 609. — Sporobolus domingensis. Plant, X 1; 

 glumes and floret, X 10. (Hitchcock 530, Fla.) 



about 2 mm. long, the first glume 

 half as long. % — Coral sand and 

 rocks along the coast of southern 

 Florida, mostly on the Keys, north 

 to Sanibel Island; West Indies. 



21. Sporobolus cryptandrus(Torr.) 

 A. Gray. Sand dropseed. (Fig. 610.) 

 Perennial, usually in rather small 

 tufts; culms erect or spreading, some- 

 times prostrate, 30 to 100 cm. tall; 

 sheaths with a conspicuous tuft of 

 long white hairs at summit; blades 

 flat, 2 to 5 mm. wide, more or less 

 involute in drying, tapering to a 

 fine point; panicles terminal and 

 axillary, usually included at base, 

 sometimes entirely included, the well- 



