73 



Fig. 51. Sporobolus longifolius (Torr.) Wood. LONG-LEAFED SPOROBO- 

 LUS.— a, A spikelet ; b, the same with the outer or empty glumes separated 

 from the flowering glume and palea; c, grain inclosed by the loose pericarp; d, 

 grain. Other species of Sporobolus are illustrated by figs. 119 to 129, in Bui. 7, 

 and 451 to 470, in Bui. 17. 



51. SPOROBOLUS R.Br. Prod. Fl. Nov. Holl. 169. 1810. Spikelets 1-flowered, 

 pedicellate, in narrow and spike-like or loose and spreading panicles; rachilla 

 articulated above the empty glumes, not produced beyond the flower. Glumes 

 3; round on the back or slightly keeled, awnless, obscurely nerved, or nerveless; 

 the 2 outer ones empty, usually unequal ; 3d or floral glume equalling or exceed- 

 ing the empty ones. Palea as long as or longer than the flowering glume. 

 Stamens 3. Styles short, distinct. Grain free, the pericarp loosely inclosing 

 the seed, or very thin and evanescent. Annual or perennial grasses with small 

 spikelets; very various in habit. 



Species about 80, a few in the Old World, but most abundant in America. 

 Thirty-eight species have been recorded from the United States. 



