GRASSES OF IOWA. 



221 



2. TRIODIA PURPUREA. 

 Triodia purpurea Hack . Watson and Coulter. Gray. Man. Bot. 658. 



1890. (6ed.) 



Tricuspis purpurea Gray. Man. Bot. 589. 1848. [Ed. l.J 



Sieglingia purpurea (Walt.) Kuntze. Beal. Grasses of N. A. 2: 

 469. 1896. Nash in Britton and Brown. 111. Fl. 1: 185. /. 121. 1896 



Triplasis purpurea Chapm. Fl . 560. 1860. 



Iriplasis purpurea (Walt.) Scribner. Bull. U. S. Dept. Agr. Div. 

 Agros. 213. f. 509. 1899. 



Aira purpurea Walt. Fl. Car. 78. 1788. 



Fig. 155. Triodia purpurea— a, empty glumes; 

 b, spike; c, empty glumes ; d, flowering glumes. (Div. 

 Agros. U. S. Dept. Agrl.) 



Fig. 156. Koeleria erislata— a, spikelet ; b. spikelet 

 expanded. (Div. Agros. U. S. Dept. Agrl.) 



Sand Grass. A smooth, erect or spreading, caespitose perennial, 

 r to 3 feet (3-9 (Sri.) high, with narrow, rigid leaves, and simple pan- 

 icles 1 to 3 inches (2-6 cm.) long. Spikelets 2 to 5-hVmered, i\ to 4 



